amateur astronomy magazinetomclark.powweb.com/aamag_upload/is91sum16/aam_91summ.pdf · amateur...

The Essent ia l Journal for Amateur Astronomers Around the World!

Issue 91Summer 2016 $6.50 US

AmateurAstronomy

Maga z i n e

Star Parties:

Equipment ReviewsiOptron iPano versus Gigapan EpicPro for Panoramic Nightscapes

Planetary Imaging PairingSky-Watcher Mak Cass and Skyris

ObservingDeep Sky TreasuresFocus on the Moon

SunspotsOutreach: Mercury Transit

Sketching Deep Sky ObjectsMilky Way Chronicles Shooting our host galaxy

Sketching the Moon

Imaging: PixInsight Workflow

Deep Sky Huntingwith Dave Tosteson

Star PeopleMike Peoples

ATMStray Light Suppression

Adventures in ATM

2 www.AmateurAstronomy.com Summer 2016 Issue # 91

Summer 2016 Issue # 91 www.AmateurAstronomy.com 3

Managing Editor: Charlie Warren Contributing Editors: Robert Reeves, John Davis, Harry Roberts, Dave Tosteson, David Lane, Andre Heijkoop Webmaster: Charlie WarrenAmateur Astronomy is published quarterly by Charlie Warren (615)-332-5555Mailing address: 511 Derby Downs, Lebanon, TN 37087 E-Mail: [email protected] Web Site: http://www.AmateurAstronomy.comCopyright 2016 by Charlie Warren. All rights reserved. Material in this publication may not be reproduced in any manner withoutwritten permission from the editor. The opinions expressed in this magazine are not necessarily those of the publisher or editors.Postmaster: Send address changes to Amateur Astronomy, 511 Derby Downs, Lebanon, TN 37087Subscription Rates : See chart on page 4.Please see our Author’s Guidelines email us for a copy or visit our website “Article and Image Submission Guidelines. Pleaseemail your articles as an attachment (MS Word, PDF or plain Text). For larger articles with a substantial number of digital photos,please send on a CD or DVD to our mail address. AA is produced on a Dell computer using Quark Xpress, Photoshop, MS Studio Suite and Adobe Studio Suite. There are no

deadlines - articles are run in the order received ASAP. Photos will be returned if requested. Addresses of authors will be printedunless otherwise requested. Preference is made for those articles received electronically by email, disk, CD or DVD Mailing dates are approximately: Winter (1/1), Spring (4/1), Summer (7/1), Fall (10/1). Delivery takes up to four weeks in the USA.

In this issue: Our Star Supporters

Amateur Astronomy

OPT Oceanside Photo & Telescope Pg 25 & 77

Celestron - page 2 &22

Sky-Watcher page 5 & 39

21 Years of Amateur Astronomy page 13

Howie Glatter’s Lasers - page 20

Space Images.com- page 22

Catseye Collimation System page 22

Eyepiece Caps - page 29

Oz Sky Adventure page 32

Equatorial Platforms - page 33

ScopeStuff - page 33

Eyepieces Etc. - page 41 & 64

Webb Deep Sky- page 44

Hotech Collimation - page 49

Charlie Bates Astronomy - page 68

Jack’s Astro MallinCam - pgs 37 & 77

Please thank our sponsors for supporting

AA and support them in return!!Don’t forget to mention that you saw their advertise-ment here. They are some of the good guys in this

hobby who make this publication possible.

Cover: Milky Way over the observing field at the TNSpring Star Party- Charlie Warren

4 Editorial

6 Short Subjects

10 Sky-Watcher Mak Cas/Skyris Review-

16 Deep Sky Hunting - Voorwerpjes by Dave Tosteson

21 NGC 5286 - Sketching DSOs - Harry Roberts

23 iPano vs Gigapan Shootout by David Lane

26 Gravity Does Not Exist by Dr. Jerry Galloway

30 Sketching The Moon by Harry Roberts

32 Star Party and Astronomical Events Calendar

34 Focus On The Moon with Robert Reeves

38 Deep Sky Treasures Seeing Dark in the Dark -John Davis

46 Star People - Mike Peoples by Robert Reeves

50 Milky Way Chronicles by David Lane

52 Stray Light Suppression - by Larry Shaper

54 Adventures in ATM - by Andre Heijkoop

59 N242 Hook and Fish - by Harry Roberts

60 PixInsight Workflow - by Jon Talbot

65 Mercury Transit Outreach by Charlie Warren

67 Sunspots by Harry Roberts

69 Star Parties by Charlie Warren

72 Parting Shots Astro men and women

Editorial


comments and updates from the Editor

I am under way on my tenth year as editor of this magazine. How time flies! A lot has changed in our hobby, as well as withprint and electronic media, but much is very much the same inregards to the relatively timeless cosmos that holds our fasci-nation.

The scale of the universe with respect to space/time alwaysprovides a check to the importance I assign to many temporalthings that occasionally capture my attention but also in juxta-position helps me esteem things I hold personally dear.Personal resources are relatively finite, and so have value. Formost of us, as we age we accumulate greater financial resourcesand more enjoyable toys for our hobby. Time unfortunatelyworks in opposition. The older I get the more valuable mydiminishing balance of time becomes in respect to everythingelse. The number of people I have known and lost accelerates;reminding me of the importance of investing in and cherishingmy encounters and relationships all the more.

This hobby, and the magazine, have given me a vast amount ofenjoyment and increased knowledge, but has, more important-ly, yielded a bounty of relationships that have tremendouslyenriched my life far beyond normal means of measure. While Ireally enjoy time alone in remote locales contemplating thebeauty of a pristine night sky. I am appreciating to an evengreater degree time spent observing with others enjoying thesky or sharing it with others through outreach.

I contributed two short articles in this issue that reflect thesevalues: “The Mercury Transit Outreach” and “Star Parties”.The former is a short recap of an outreach event at a localschool for the May 9th transit of Mercury. What started as asmall event grew into an outreach to 800+ students and sorequired resources well beyond my own. Five local amateurastronomers took time off work and joined me in providing afirst class experience for these students. In addition, StephenRamsden of the Charlie Bates Solar Astronomy Project expe-dited shipment of enough solar glasses for all the students andDavid Eicher of “Astronomy” magazine expedited shipment ofintroduction to astronomy brochures for the kids. After all theyears I have been involved, I suppose I should come to expectthese types of selfless responses from individuals involved inthis hobby; but it still humbles me and makes me exceedinglyglad for the community that we share. The 2nd article is just ageneral reminiscing of some great times spent at recent starparties. Through both of these, I hope to encourage others to

expand their opportunities to band together and share their loveand knowledge of the universe with others at star parties andoutreach events. Looking back, I have never thought I shouldhave done less of these activities, rather I always reflect that Ishould have taken the time to do more. Going forward, I planon doing significantly more of both and hope everyone readingthis will pledge to as well.It is time well spent with people wellworth spending it.

Going Forward: Color, Print and an ApologyI am asked frequently if we will be going to color anytime soonin the print version. The answer is “probably not”. With therealities of small press, the trade off for us was reduced paperquality and a staple/fold format with color, or upgrade the qual-ity of paper/gloss and stick with a perfect binding format. Forabout 90% of our content, I would say the higher quality paperand print serves our readers better and is my strong preference.The digital version does provide an alternative for those whodo desire color content

The above is a good segue to topic two. Closely aligned withthese decisions, is the question whether we will ever discontin-ue our print version. My strong preference here is also “no”.Our digital footprint already exceeds our print and it wouldprobably be more viable financially even now, but I truly likeseveral things about a printed format. There are large and con-stantly growing costs associated with printing and mail distri-bution. That said, there is a legitimacy to a publication thatprints in this digital age. There is a plethora of informationavailable on the Internet. A substantial portion is poorlysourced, edited or outright errant. There is a substantiallygreater commitment to the indelibility of print. There is somereally good online content and blogs that I enjoy, but the reali-ty is many of these are produced with the idea that they willhave an expiration date of hours or days . The content can beedited or updated on the fly. When you commit something toprint, your decisions (and errors) stare you in the face with afinality that can last years, even decades, which generally leadsto a greater fiduciary commitment to the content.

Which is a great segue to topic three. I take great pride in ourmagazine, even while being extremely cognizant of my limita-tions and fallibility as an editor. Ed Turco’s nice article “TheDefinitive Newtonian” last issue had a redundant paragraphand several other paragraphs hidden under the “Nervo Quiz”sidebar. The attempt to correct the first issue ended up withboth errors on the final version uploaded to the printer ratherthan the correction. The obscured text has been re-printed onpage 9 of this issue. I have been and will continue to provide adigital version of the issue to any print subscribers who wouldlike the corrected version intact. My apologies to our readersand particularly Ed - all of whom have been very graciousabout this egregious error. As I stated above the commitment toprint is greater than digital and errors considerably more hum-bling and painful, but that makes for a better and more memo-rable learning experience.

Charlie


Short SubjectsShort Subjects

Amateur Astronomy Magazine Subscription Information:

Single issues – $7 for a sample issue pp in the US. $8 to Canada and $12 to others outsidethe continental US.

1-Year rate Two Year rateUSA subscriptions $24 $44Canada - first class $32 $60Mexico - first class $38 $72Overseas - airmail $55 $110Electronic PDF $18 $35Dual Print & pdf - add $10 $16

to any of the print subs

All Credit cards are accepted on our website, or if you prefer, you can call in your order to our office(615-332-5555) anytime. You can also print the online form and send in your check or credit cardpayment to 511 Derby Downs, Lebanon, TN 37087

Your subscription will start with the current issues unless stated otherwise. Subscribe or renew today at www.amateurastronomy.com

Rosetta: type of ice reveals theage of cometsThe ice buried inside comet 67P/Churyumov-Gerasimenko is mainlyfound in crystalline form, whichimplies that it originated in the protoso-lar nebula and is therefore the same ageas the Solar System. This discoverywas made by an international team ledby a researcher at the LAM1(CNRS/Aix Marseille Université) andalso including scientists from theLaboratoire J.-L. Lagrange(OCA/CNRS/Université Nice SophiaAntipolis) and the Centre deRecherches Pétrographiques etGéochimiques (CNRS/ Université deLorraine), with support from theCNES. Their findings were obtained byanalyzing data from the Rosina2 instru-ment, placed on board ESA's Rosettaspacecraft. This work has been pub-lished on 08 March 2016 in TheAstrophysical Journal Letters.Little by little, the Rosetta mission isuncovering the secrets of comets, andhas now succeeded in settling adecades-old debate about the nature oftheir ice. Until now, there were twoopposing hypotheses, one that the ice iscrystalline, and the water molecules arearranged in a regular pattern, and theother that the ice is amorphous, and the

Figure 1. N2/CO and Ar/CO ratios in Churi measured by Rosina, com-pared to laboratory data and models. The green and blue areas representrespectively the variations in N2/CO and Ar/CO ratios measured by theRosina instrument (Rubin et al. 2015; Balsiger et al. 2015). The blackand red curves show respectively the evolution of N2/CO and Ar/COratios in gas hydrates calculated according to their formation tempera-ture in the protosolar nebula. The black and red dots correspond to lab-oratory measurements of N2/CO and Ar/CO ratios trapped in amorphousice (Bar-Nun et al. 2007). The two vertical dotted lines show the temper-ature range allowing the formation of gas hydrates with N2/CO andAr/CO ratios consistent with the values measured in Churi.


water molecules are disordered. Thisquestion is especially importantbecause of its implications for the ori-gin and formation of comets and theSolar System.

The issue has now been settled thanksto the Rosetta spacecraft's Rosinainstrument. This is a mass spectrome-ter, which in October 2014 first meas-ured amounts of molecular nitrogen(N2), carbon monoxide (CO) andargon (Ar) in Churi's ice. The data wascompared with that from laboratoryexperiments on amorphous ice, as wellas from models describing the compo-sition of gas hydrates, a type of crys-talline ice in which water moleculescan trap molecules of gas. The ratios ofmolecular nitrogen and argon found inChuri correspond to those in the gashydrate model, while the amount ofargon detected in Churi is a hundredtimes smaller than the quantity that canbe trapped in amorphous ice. The icein the comet therefore definitely has acrystalline structure.

This is a major discovery, since it

makes it possible to determine the ageof comets. Gas hydrates are made ofcrystalline ice that formed in the proto-solar nebula (which gave rise to theearly Solar System) from the crystal-lization of grains of water ice and theadsorption of gas molecules onto theirsurfaces as the nebula slowly cooled. Ifcomets are made of crystalline ice, thismeans that they must have formed atthe same time as the Solar System,rather than earlier in the interstellarmedium. The crystalline structure ofcomets also shows that the protosolarnebula was hot and dense enough tosublime the amorphous ice that camefrom the interstellar medium. The gashydrates agglomerated by Churi musthave formed between -228 °C and -223 °C to produce the observed abun-dances. This work also lends weight toscenarios for the formation of the gasgiant planets, as well as their moons,which require the agglomeration ofcrystalline ice.

Repetitive patterns found in myste-rious cosmic bursts of radio waves

Columbia, Md., March 3, 2016 - Withthe help of the world’s largest radio tel-escope, the Arecibo Observatory,astronomers have, for the first time,detected repeated bursts of radiowaves from a source well beyond theedge of our Milky Way galaxy. Theorigin of these “fast radio bursts”(FRBs), lasting only one thousandthsof a second, is a decade-old puzzle inastronomy.

Prior to this discovery, reported inNature, all previously detected FRBshave appeared to be one-off events.Despite extensive efforts, astronomersuntil now have failed to detect repeat-ed bursts. “Our discovery shows thatat least some FRBs must originatefrom something like a super-high-powered rotating neutron star that canregularly emit extremely bright puls-es,” says Laura Spitler, postdoc at theMax Planck Institute for RadioAstronomy and lead author of thepaper. “This is a crucial step in deter-mining what causes these bursts,which appear to originate in galaxiesfar beyond our Milky Way.”

“Without the Arecibo Observatory,most, if not all, of these events wouldhave gone unseen,” according toAndrew Seymour, a postdoc at theArecibo Observatory in Puerto Rico.The Observatory houses the world’slargest and most sensitive dish singledish telescope– 1000 feet in diameter.

Multiple events from the same locationwere confirmed by McGill Universitygraduate student Paul Scholz withresults from observations performed atArecibo. The new data, gathered inMay and June and run through a super-computer in Montreal, Canada,showed bursts with properties consis-tent with a FRB detected two yearsearlier (in 2013) by the same team.

The repeat signals were surprising –and “very exciting,” Scholz says. “Iknew immediately that the discoverywould be extremely important in thestudy of FRBs.” As his office matesgathered around his computer screen,


Scholz pored over the remaining output from specializedsoftware used to search for pulsars and radio bursts. Hefound that there were a total of ten new bursts.

Scientists believe that these and other FRBs originate fromdistant galaxies, based on the measurement of an effectknown as plasma dispersion. Pulses that travel through thecosmos are distinguished from man-made interference bythe influence of interstellar electrons, which cause radiowaves to travel more slowly at lower frequencies. The tennewly detected bursts, like the one discovered in 2013, havethree times the maximum dispersion measure that would beexpected from a source within the galaxy.

In future research, the team hopes to identify the galaxywhere these radio bursts originated. Using a techniquecalled interferometry, performed with radio telescopesspread over large geographical distances, astronomers willbe able to achieve the needed resolution. “Once we have aprecise location, we will be able to compare observationsfrom optical and X-ray telescopes and see if there is agalaxy at that location; this will be the next breakthrough,”says Jason Hessels, associate professor at the University ofAmsterdam and ASTRON, the Netherlands Institute forRadio Astronomy as well as corresponding author of theNature paper. “Finding the host galaxy of this source is thenext step in understanding its properties”, he adds.

“Now with multiple events from the same location, we canstart to zero in on the actual cause and we won't be forced to

speculate much longer”, explained Seymour. The Arecibo Observatory is operated by SRI International

in partnership with Ana G. Méndez University System-Universidad Metropolitana and Universities SpaceResearch Administration (USRA) under a cooperativeagreement with the National Science Foundation. Theresearch was supported by grants from the EuropeanResearch Council, the National Science and EngineeringCouncil of Canada, and the American National ScienceFoundation.

The Moon thought to play a major role in maintaining

Earth's magnetic fieldThe Earth's magnetic field permanently protects us from thecharged particles and radiation that originate in the Sun.This shield is produced by the geodynamo, the rapid motionof huge quantities of liquid iron alloy in the Earth's outercore. To maintain this magnetic field until the present day,the classical model required the Earth's core to have cooledby around 3 000 °C over the past 4.3 billion years. Now, ateam of researchers from CNRS and Université BlaisePascal1 suggests that, on the contrary, its temperature hasfallen by only 300 °C. The action of the Moon, overlookeduntil now, is thought to have compensated for this differenceand kept the geodynamo active. Their work is published on30 march 2016 in the journal Earth and Planetary ScienceLetters.

The classical model of the formation of Earth's magneticfield raised a major paradox. For the geodynamo to work,

The gravitational effects associated with the presenceof the Moon and Sun cause cyclical deformation ofthe Earth's mantle and wobbles in its rotation axis.This mechanical forcing applied to the whole planetcauses strong currents in the outer core, which ismade up of a liquid iron alloy of very low viscosity.Such currents are enough to generate the Earth'smagnetic field. © Julien Monteux and DenisAndrault.


the Earth would have had to be totally molten four billionyears ago, and its core would have had to slowly cool fromaround 6800 °C at that time to 3800 °C today. However,recent modeling of the early evolution of the internal tem-perature of the planet, together with geochemical studies ofthe composition of the oldest carbonatites and basalts, do notsupport such cooling. With such high temperatures beingruled out, the researchers propose another source of energyin their study.

The Earth has a slightly flattened shape and rotates about aninclined axis that wobbles around the poles. Its mantledeforms elastically due to tidal effects caused by the Moon.The researchers show that this effect could continuouslystimulate the motion of the liquid iron alloy making up theouter core, and in return generate Earth's magnetic field. TheEarth continuously receives 3 700 billion watts of powerthrough the transfer of the gravitational and rotational ener-gy of the Earth-Moon-Sun system, and over 1 000 billionwatts is thought to be available to bring about this type ofmotion in the outer core. This energy is enough to generatethe Earth's magnetic field, which together with the Moon,resolves the major paradox in the classical theory. The effectof gravitational forces on a planet's magnetic field hasalready been well documented for two of Jupiter's moons, Ioand Europa, and for a number of exoplanets.Since neither the Earth's rotation around its axis, nor thedirection of its axis, nor the Moon's orbit are perfectly regu-lar, their combined effect on motion in the core is unstableand can cause fluctuations in the geodynamo. This processcould account for certain heat pulses in the outer core and atits boundary with the Earth's mantle.

Over the course of time, this may have led to peaks in deepmantle melting and possibly to major volcanic events at theEarth's surface. This new model shows that the Moon's effecton the Earth goes well beyond merely causing tides.

The Definitive Newtonian Text obscured by the Nervo Quiz on page 21 of Issue 90 pick-ing up from the third paragraph

Some may rightly point out that my window seals off thetube and totally interferes with the flow of air though thetube. But please remember that my dark bucket has a remov-able back to let more than enough air out its side to cool thesetup down and eliminate those tube currents. An hour ofusing the fan to drive air through the mirror cell, past themirror, and out the side cools things down within. And withthat, I can close the door to the dark bucket and turn off thefan. Note that the door to the dark bucket rests against aninternal ring that prevents light leakage from this quarter,just as I used as a “stop” for my mirror cell to get the sameeffect.

You may have noticed that I have been mentioning some ofthe less obvious defects of an ordinary Newtonian reflector.The reason for this is my wish to get all of these cleaned up

to show a clear diffraction image of a star unencumbered bythese errors. We now have the best diffraction image we canget at the eyepiece. Think of it this way; if the large num-bers of diffraction patterns that define a planet’s image allhave spikes; the nearest analogy is looking at a soft half-toneimage from a newspaper. Curved spiders spread thesespikes’ light through the entire field with a faint haze. Ithink of the above problems as a subtle “mud” that degradescontrast. Interestingly, these effects can not be readily sub-jected to mathematical analysis. One might not directlysense this haze, but it is there and surely lowers contrast. Itis dramatically shown below:

This type of problem can only be entirely eliminated with anoptical window. It is assumed, even among experiencedATMs that making a window is a very hard chore, but noth-ing could be farther from the truth. Actually, neither of thewindow’s faces need to be flat to 1/20 wave as many haveoften stated. I have seen optical windows that were out offlatness by 5 waves on each surface withabsolutely no effect on diffraction patterns. It is true thatoptical glass is needed, and one must learn the techniquesthat are readily available. But the main importance in theproduction of an optical window is that it needs to be of uni-form thickness, and that its surfaces must be regular with nozones. Such a window can be made by an experienced ATMif he would only try.

This discussion continues with the issue of obstruction inthis telescope. Many Newtonians of the short focus varietyoften have obstructions of 30% or more. Longer focus tele-scopes often get by quite well with a 25% obstruction, yield-ing images that are quite passable. Suiter in Star TestingAstronomical Telescopes states that an 18% or lowerobstruction, yields diffraction images that are imperceptiblydifferent than those in an unobstructed refractor. ATMs havestruggled to attain this number in their own instruments, byusing low profile focusers and smaller tube diameters tolessen the distance between diagonal and prime focus. Thislatter strategy conflicts with the problem of air currents andnarrow tube clearances. But with the effort, the 18% ratiocan be achieved.


All images taken by Robert Reevesthrough the Sky-Watcher 180mmMaksutov with a Celestron Skyris 236Mcamera

For the past several months I havebeen using a new telescope formy lunar photography. After

giving the scope a shakedown overseveral lunar cycles, I have to say thatthe Sky-Watcher 180mm Maksutovhas to be one of the best kept secrets inplanetary imaging. The Maksutovdesign is an F/15 system with a result-ing 2700mm focal length, thus the tel-escope is primarily a solar systeminstrument. Also for the past month Ihave been using Celestron’s newSkyris 236M planetary camera withthe Sky-Watcher Mak for my lunarimaging. I have been a lunar photog-rapher for more than 50 years and I

continue to be amazed by the results Iam getting through the Sky-Watcher180mm Mak with the Skyris 236Mcamera. The images pop with detailand contrast that scream “large expen-sive telescope”. When I look at theimages, I have to remind myself theywere taken with a very affordableseven-inch telescope!

The first thing I noticed when shootingthrough the Sky-Watcher Mak was aboost in image contrast. For the past40 years I used Schmidt-Cassegraintelescopes for my lunar shots. Duringthat time I have heard anecdotally thatMaksutov telescopes provide higherimage contrast. I can now personallyconfirm that! The jump in image con-trast forced me to alter my image pro-cessing workflow from that previously

used with images taken though anSCT. I find that with the Mak, I nolonger need to perform some of thewavelet image sharpening steps inRegiStax.

The Sky-Watcher Maksutov is a phys-ically attractive telescope with a star-speckled black tube that contrasts withthe white accents of the mirror andcorrector plate supports. I am alsoimpressed with the mechanically solidfeel of the Sky-Watcher 180mm Mak.The tube is slightly narrower and a lit-tle longer than a common 8-inch SCT,but it has the feel of a tough littleinstrument that is not overly delicate.The 180mm Mak comes standard witha 2-inch diagonal and a 28mm eye-piece. The telescope tailpiece has theindustry standard threads used by both

Sky-Watcher and Skyris, a Powerful andAffordable Duo for Planetary Imaging

Robert Reeves

The Sky-Watcher 180mm F/15 Maksutov is a physically beautiful telescope that is an outstanding performer forviewing and imaging solar system objects. The Sky-Watcher Mak attaches to any mount capable of carrying a 8-inch SCT. If the attached Sky-Watcher dovetail bar is incompatible with your mount, simply bolt your bar direct-ly to the Sky-Watcher bar. For best imaging results when using a Barlow, an aftermarket Crayford slow motionfocuser simplifies the camera focusing process. Right: This view is dominated by the grand craters Langrenus at top and Petavius at bottom. Both craters arefresher and brighter than nearby Vendelinus and display strikingly bright rims in sunset illumination. The lowsun accentuates the clockface riles within Petavius which seem to perpetually show “20 minutes to 12”..


Celestron and Meade Schmidt-Cassegrain telescopes, so all imagingaccessories that universally fit thesebrands will also work on the Sky-Watcher. The 8 X 50 straight throughfinder provides a clear and contrastyview with well-focused crosshairs.

Like the familiar SCT telescope, theSky-Watcher Mak focuses by movingthe primary mirror. The focuser issmooth and responsive with no back-lash and is adequate for imaging at“prime focus”. If I use a 1.5X Barlowwith the Sky-Watcher, pushing it toabout 4000mm focal length at F/23, Ifind it best to add an aftermarketCrayford focuser with slow motion

controls to get the best performance.Another plus with the Maksutov is notan actual feature, but an effect createdby the telescope’s optical design. TheMaksutov corrector plate is muchthicker and heavier than a Schmidt-Cassegrain corrector. The thicker glassretains heat longer and thus the Mak ismore dew resistant than an SCT. Withthe Sky-Watcher 180mm Mak I havebeen able to continue imaging long pastthe point where my SCT correctorswould have fogged.

As much as I like the performance ofthe Sky-Watcher 180mm Mak, I dohave two minor quibbles about thescope. The first is that the tube’s black

finish, as visually beautiful as it is,requires that the scope be kept out ofthe sun for several hours before sunsetor the scope becomes quite hot andtakes a while to cool and reach thermalstability. However, I think the Sky-Watcher is such a pretty scope that Ilive with this facet and simply keep itcovered until sundown. My secondminor grump is the Mak’s finder brack-et seems to be installed “backward”. Ifthe finder’s dovetail mount screw isloose while the telescope is aimedupward, the finder will slide out andfall. The bracket should be turnedaround so it is failsafe when the scopeis aimed upward.

Left: The sunset shadows across Mare Crisium reveals the entire ring of wrinkle ridges that circle the mare justoffshore. Shadowed Dorsum Oppel lies on the western side and brightly lit Dorsum Tetyaev and Dorsum Harkeron the eastern side. The two largest craters within Crisium, Pierce at top and Picard at bottom, are almost loston the empty plains. The spray of spiderweb like rays across western Crisium come from Proclus, the brilliantoverexposed crater at image center left edge.Right: The lunar strongman, Hercules on the left and Atlas on the right, present two different crater appear-ances. Hercules is a traditional lava flooded crater while Atlas presents the “oatmeal cookie” pattern on itsfloor indicative of a floor-fractured crater that was modified by volcanic uplift. To the upper right of the strong-man lies dark lava-flooded Endynion.


The Sky-Watcher 180mm Mak is soldas an optical tube only. It comes withan attached dovetail bar. If the bar isincompatible with your mount, simplybolt a compatible bar onto the Sky-Watcher bar using the available pre-drilled threaded holes in the Sky-Watcher bar. Both metric and standardholes are pre-tapped. Any mounts thatcarry a standard 8-inch SCT will easi-ly carry the Sky-Watcher 180mm Mak.If you have to attach another dovetailbar that does not line up with the holesin the Sky-Watcher bar, as happened tome, I’ll let you in on a secret that is notin the non-existent Sky-Watcher Mak

user’s manual. Yes, I am being face-tious, but the telescope is so simple touse that a user manual is not necessary.However, if you need to remove theattached dovetail bar by unthreadingtwo 3-millimeter allen screws, youmust first remove the corrector platebecause the internal screw anchors arenot captive, they will drop loose insidethe tube. Before removing the correc-tor cell, place tabs of tape on the tubeand cell edge so they will be properlyaligned when reassembled. The cor-rector cell comes off by removing four2.5mm allen screws around its rim andgently pulling the cell free from the

tube. Beware that the corrector isdeceptively heavy. Don’t let it getaway from you! After modifying thedovetail bar, slide the corrector cellback in place, aligning the tape tabs,and tighten the four screws whileexerting slight pressure to seat the cellonto the tube.

Prior to removing the corrector cell onmy Sky-Watcher Mak, I verified thecollimation was good by using aHotech Advanced CT laser collimator.I was impressed that after reassem-bling the corrector cell, the collimationwas still spot on.

Left: At lower center are the deeply shadowed craters Aristoteles and Eudoxus. The rim of Aristoteles, the larg-er of the two, is obviously not of equal height across its western side as the shadow within the crater floor hasa curious double hump that allows the setting sun to linger a little longer on the central peak. At the upper leftlies the ruined distinctly square crater W. Bond.Right: The triple craters at upper left are flat floored Ptolemaues at top, previously volcanically activeAlphonsus at middle, and floor fractured Arzachel at bottom. Within Alphonsus seven dark ash deposits can beseen around the crater’s rim and floor. At the upper right we see Hipparchus at top and Albategnius just belowit, looking like fraternal twins of nearby Ptolemaeus and Alphonsus. To the south we also see heavily ruinedPurback at lower left, unusually well defined Werner at bottom center, and equally round Aliacensis with itsdebris filled floor at lower right.

In a nutshell, as an experienced lunarimager I am truly impressed with“feel” and performance of the Sky-Watcher 180mm Maksutov, and with a$1275 price tag, I consider it a bargain.

Now I’ll tell you about the other halfof my lunar imaging setup. Celestronhas added a new model to their vener-able line of Skyris solar system imag-ing cameras. The Skyris 236M (mono-chrome) and 236C (color) versionsexpand the celestial imaging industry’sshift to CMOS sensors. Being a lunarphotographer, I use the Skyris 236Mbecause the Moon is basically a black

and white target. I find the 236M isboth more sensitive and produces lessimage noise than the previous SkyrisCMOS camera. The 236 retains thesame heat-dissipating ribbed alu-minum case as previous versions of theSkyris. The camera’s 3.6 ounce massis lighter than most eyepieces and cre-ates no telescope balance issues. Likeprevious Skyris cameras, the 236 ispowered entirely through the USB3cable.

All Skris cameras lack a threaded holein their base where a safety lanyardcan be attached. However, the thread-

ed lock screws on the camera end con-nector of the robust USB3 cable aremore than capable of supporting theSkyris in case it slips out of thefocuser. The trick is loop the USBcable over the telescope finder to sup-port the camera in case it does slipfrom the focuser.

The Skyris 236 uses the Sony EXMORIMX236LQJ sensor. As with otherSkyris cameras, the camera’s modelnumber mirrors the numerical designa-tion of the sensor used. The 236 modelSkyris has 2.8 micron square pixels,resulting in 33% higher image magni-


Left: Near the middle of the Moon's visible disk we see many examples of rilles, or channels across the face ofthe Moon. At the upper left are the tangled Triesnecker rilles. Just east of the Triesneckers, we see the gullwing pattern of the linear Hyginus Rilles. The most prominent in this view are the Ariadaeus Rilles at imagecenter. Looking like a slash from a sword fight, the Ariadeaus Rilles are actually a feature called a graben, orslumping land between parallel faults. Within the twilight shadows along the eastern shore of MareTranquilitatis we see the Sosigines rille above the termination of Ariadaeus and the Ritter rile below.Right: The topographic elevation of this view is above the lunar average “sea level” and the Moon's early vol-canism did not deposit vast areas of basalt in this region. At the upper left we see the unusually well definedcrater Werner. This area is so jammed with craters, many of similar size, that it is difficult to single out “land-mark” craters. The best known other craters in this view are Stofler and Maurolycus, the largest craters seenside by side just below image center. These two large craters have been overlain by subsequent impacts thatmodified their form as well as peppered the surrounding region with wall-to-wall craters.


fication over the 3.75 micron pixels inthe Skyris 132 when used on the sameoptical system. The new camera has a1200 X 1920 pixel array on a 5.44 X3.42 mm sensor size, which takes a lit-tle getting used due to the 236’s elon-gated image format. The Skyris 132’soutput is proportional to the 8 x 10 inchprint format while the new Skyris 236output is closer to a 5 X 7.

High sensitivity and low image noiseare valuable assets when imaging thedim lunar terminator at long focallengths. The Skyris 236 possessesthese characteristics and producesamazingly smooth images. At F/15along the quarter moon terminator,shutter speeds average three to fivemilliseconds with the gain set at midrange. The camera is capable of expo-sures as brief as 1/10000 of a secondand as long as 10 seconds, and it can beused as an autoguider with PhDGuiding software.

The frame rate with the Skyris 236 isfast, up to 60 full frames per secondwith a USB3 connection. The camerais backward compatible to USB2,though at only 15 full frames per sec-ond with the slower connection. WithROI, or “region of interest” cropping toa small frame size more suited to plan-ets, and a USB3 connection, the camerais capable of up to 200 frames per sec-ond. Of course, such a high frame rateis possible only if the shutter speed isfaster than the reciprocal of the framerate. That is, if imaging at 200 framesper second, the shutter speed cannot belonger than 1/200th of a second.

CMOS sensors use what is known as a“rolling shutter”, that is, the image isexposed scan line by scan line from oneside of the frame to the other. This con-trasts with CCDs where all pixelsexposed at once and the image isfrozen. As long as the telescope issteady and not shaking in a strongwind, I have never had a problem withimages produced by a CMOS rollingshutter.

The Skyris 236M monochrome versionlacks a filter in front of the CMOS sen-sor, thus it is sensitive to IR wave-lengths. Since IR wavelengths focuson a different plane than visible light, itis recommended that an IR filter be

used with the 236M camera. Theindustry standard 1 ¼-inch filtersthread directly into the Skyris nose-piece and double as a sensor dustshield.

The Skyris’ electronics creates imageswith a 12-bit A/D conversion. Whenseveral hundred images are stacked inone of the popular image stacking soft-ware suites, effective bit depth isincreased further. This allows plenty oflatitude for stretching a shadowed areaalong the lunar terminator or dimminga saturated highlight.

The use of CMOS sensors in today’splanetary cameras is a win-win situa-tion for those who like to image boththe Moon and smaller planetary targets.CMOS sensors like the one used in theSkyris 236 are competitive with CCDsensors in sensitivity and low imagenoise and CMOS are less costly, givingus superior cameras at affordableprices. Moon photographers use thefull field of view when capturing widelunar vistas, but planetary CMOS cam-era users employing “region of inter-est” cropping also enjoy dramaticallyincreased frame rates, something CCDsensors cannot do.

So what is the bottom line? I believethe combination of Sky-Watcher180mm Maksutov telescope and Skyris236 camera is a powerful system offer-ing outstanding planetary imaging per-formance at an affordable price. TheSkyris 236 suggested retail price of$479.95, when combined with the Sky-Watcher 180mm Maksutov, produces asub-$2000 planetary imaging systemthat outperforms what large profession-al observatories could do severaldecades ago. Indeed, the Sky-Watcher/Skyris combination producesimages that look like the product of amuch larger telescope. Like I saidbefore, I have to constantly remindmyself that the amazing results camefrom a 7-inch telescope! I highly rec-ommend the Sky-Watcher Maksutovand the Skris 236 camera to anyonewho has a passion for the Moon andplanets and is looking for an affordableimaging system that can produceresults that would please even seasonedplanetary astronomers.

His Eminence, Professor, DoctorNervo Shatterini, wishes all a joyousand astronomically productiveSummer to his quizophiles.

(1) What is Absolute Zero?

(2) To what does the Hawking Effect

relate?

(3) How many stars are involved in a

periastron?

(4) If a star was "blue shifted" where

would it be going relative to Earth?

(5) Which star is used as the standard

for Magnitude 0

(6) Which is the brightest

Constellation in the sky?

(7) Which Constellation is related to

the Golden Fleece?

(8) How many stars are in the SAO

Catalog?

(9) When is a Full Moon not visible

from the South Pole?

(10) Who discovered in 1650 that

Mizar had a telescopic companion

star?

(12) What is the approximate diameter

of the Milky Way galaxy?

(13) How many eyes did the mythical

Argus have?

(14) Who is currently the Patron Saint

of Australia?

(15) How long does it take light to

reach us from the Sun?

(16) Which Observatory burnt down

near Canberra?

(17) Which volcano is used for astron-

omy?

(18) Which Australian has discovered

the most comets visually?

(19) In which Constellation is Merak?

(20) Which constellation is between

Dorado and Tucana?

Answers on Page 23


On July 10, 2007 astronomers atOxford University in Englandinvited the public to assist in

their research in classifying one mil-lion galaxies from the Sloan DigitalSky Survey. Expecting a limited initialresponse, the result of their “GalaxyZoo” project was beyond expectation:70,000 contributions poured in hourlyduring the first day! More than fiftymillion classifications were collectedby the end of the experiment, assistingastronomers in numerous ways. Withnew looks at the Universe, unexpectedresults always occur, one of which wasan unusually shaped and coloredobject next to the tilted spiral IC 2497in southwestern Leo Minor. Dutchschool teacher Hanny van Arkel foundthis object, and it was intensively stud-ied because it defied initial explana-tion. Its name, “Hanny’s Voorwerp”, isa term for “object” in Dutch. Nosource for an energizing output couldbe found for this ionized region of gas.The conclusion best fitting the datawas that the nearby spiral galaxy host-ed an actively emitting quasar in itscore that had once energized the ver-dant, but shut off 70,000 years ago.

In his 2010 Astrophysical JournalLetters article on “The Sudden Deathof a Nearby Quasar”, Schawinskicalled IC 2497 the first measurement

of a shutdown timescale for a quasar.He estimated a 10,000 fold decrease inoutput over 70,000 years. The core ofthis galaxy was noted to be “cold” inthe infrared using the IRAS satellite,compared to nearby, luminous and

obscured AGNs, indicating its enginewas inactive. The x-ray satellitesSuzaku and XMM-Newton also foundinsufficient energy in that spectralregion to classify it as an active quasar,but they did see enough to call it a low-level AGN. When told of the x-rayresults by the author, Bill Keel dead-panned, “It’s dead, Jim”, but it may bemore appropriately considered hiber-nating. Supermassive black holes atthe center of galaxies may all be sleep-ing giants, somnovores awaiting stim-uli to reawaken.

With its new designation as a quasar,IC 2497 is one of, if not the closest ofits kind. Given a redshift of 0.0502, itslight travel time to us is 681 millionyears. Its “voorwerp”, or region of ion-ized gas, is 45-70,000 light years fromthe center of the galaxy, and is 36 by52 thousand light years in size.Imbedded in a larger region of molec-ular hydrogen, it contains one billionsolar masses. Its spectrum is mostlythat of doubly ionized oxygen (OIII) atthe 5007 Angstrom line, with little of acontinuum spectrum present. Thus itsveridity, and our potential advantagefor narrowband filters enhancing its

Observer’s Corner - Deep Sky Hunting

Voorwerpjes and TrebuchetDave Tosteson

Tilted spiral IC 2497 and the ionized region of gas below it known asHanny’s Voorwerp. Discovered by school teacher Hanny van Arkel.


view at the eyepiece. Several smallgalaxies lurk in the area, andresearchers have modeled that a tidalstream drawn out of IC 2497 by one ofthem is the structure ionized by thequasar. So the passing dwarf likely diddouble duty, causing both the tidalstream and activation of the quasar.Hanny’s Voorwerp was seen by a num-ber of observers at the 2012 Texas StarParty through Larry Mitchell’s 36” tel-escope, and several people using JimiLowrey’s 48” reflector reportedimproved views using a green Astrodonfilter.

William Keel of the University ofAlabama took an interest in this objectand with extensive research located anumber of similar structures. In 2012he published a paper identifying 154candidates, and in March of 2015 pub-lished another on eight confirmed“voorworpjes” studied with the HubbleSpace Telescope. In that arXiv articleon the host galaxy and the origin of the

IC 2497 is not listed on this StarryNight chart below, but it liesabout 15 arc minutes from 13Leonis Minoris at the center ofthis Telrad finder. It is almostmidway on a bisecting linebetween 21 Leonis Minoris andAlpha Lynx

Other Voorwerpjes

extended gas, he noted AGN ionizedgas to over ten kiloparsecs from thenucleus, and that the fading of thevoorwerp was on the timescale of50,000 years. All eight of the galaxiesstudied showed signs of interactionincluding tidal tails, shells and warpeddiscs. Two of them showed new starclusters within the ionization cone ofthe quasar, but the correlation of theAGN being the cause of their originwas felt to be weak.

At the 2015 Texas Star Party theweather was unsettled, but there weresmall blocks of time with clear skiesand steady seeing. Taking what wasgiven, I used my chart to locate NGC5972, one of the brightest voorwerpjesin Keel’s study, whose ionized regionswere visible on the POSS 2 plates.Located 2.3 degrees northwest of BetaSerpens, at the base of its triangularhead and in the middle of the 8 “tau”stars, it appears on HST imaging as aslightly flattened lenticular galaxywith a complex, warped disc of gascrossing the center plane. The green,ionized gas looks to be in two overlap-ping “S”-shaped components forminga loop-like structure just off the south-ern end of the central portion of thegalaxy, with a tail extending 30” to thenorth of its core. Using my 32 inchreflector both these structures on thenorth and south ends of the galaxycould be spotted with a 5 mm eyepieceyielding 650X. On the upper field atthe Prude Ranch, I was sandwichedbetween my friend Tim Parson, andCharlie Warren, editor of AmateurAstronomy magazine. Both came overto confirm the observation, and inmoments of good seeing I could makeout complexity over and around thegalaxy. The images from HST wereinvaluable, as the detail on the POSS issubtle. The skies that week did notallow extended opportunity for thistype of observing, but the Palomarimages of some of the other voorwerp-jes from Keel’s paper suggest severalwill be visible under excellent condi-tions.

The pursuit of new and interestingphenomena at the edge of science chal-lenges our skills and pushes our hobbyforward. As is usually the case, initial

sightings in larger apertures are oftenfollowed by success with smaller mir-rors. These voorwerpjes will provide achallenge to deep-sky visualobservers, but more will certainly bespotted as the sky slowly releases itssecrets.

Trebuchet

Besieging armies in medieval timescarried a variety of weapons to assailthe fortified walls of defending cities.None was more feared or effectivethan the trebuchet, which hurled largerocks great distances to quickly reducestone walls to rubble. By using leverarm forces and a heavier weight on theopposite end, the simple force of grav-ity was enough to throw its very offen-sive projectile with devastating power.Astronomers have used gravitationaltheory to model a not dissimilar sce-nario: the interaction of two supermas-sive black holes at the center of merg-ing galaxies. As the two galaxiesapproach, theorists have anticipatedblack holes inhabiting their centerscould perform such a pas de deux as toimpart one with enough velocity toescape to intergalactic space. Recentstudies of a quasar in Leo show obser-vations may be confirming theory so,one might say, on a larger scale theweight is over. Or is it?

Gravitational theorists have pre-dicted a pair of merging black holes atthe center of a galaxy-galaxy interac-tion may produce asymmetric gravita-tional waves as they spiral toward eachother. If this imbalance in forces werelarge enough, one of the black holeswould be ejected from the core. Highangular momentum and the directionof the black holes’ spin are factored into how the scene plays out.Speculation about such “recoil” eventsestimate how many black holes may befloating in the disc and halo of largergalaxies. In the mid 2000’s these theo-ries evolved to show ejected blackholes could achieve velocities in thethousands of km/s, high enough toescape the largest elliptical galaxies. In2008 Stephanie Komossa of the MaxPlanck Institute for Physics and hercolleagues announced the discovery ofa quasar in NW Leo with unusual spec-troscopic qualities. From her search ofthe Sloan Digital Sky Survey shefound SDSS J092712.65 +294344.0, aquasar with two sets of emission linesshowing a large velocity difference of2,650 km/s. Her interpretation of thisobject was that the broad emissionlines were associated with a supermas-sive black hole (defined as over onemillion solar masses) ejected from thecore of a merging galaxy pair.

A claim of identifying the firstspecimen of a new class of objects


Illustration of Komassa merging Black Holes


tends to spark lively debate, and SJ0927 was no exception. Over the nextseveral years other theorists andobservers parleyed alternative explana-tions. Binary quasars were considered,but the velocity difference inferred inthe spectra exceeded those seen in mostgalaxy clusters. Interpreted as a stan-dard redshift distance, their differenceimplied a separation of 100 mega-parsecs, with an extremely close visualseparation of two very unusual quasars.Statistically, this was an extremely lowpossibility, estimated to be one chanceor less for the over 100,000 knownquasars. In 2009 Dotti proposed a tightpair of supermassive black holes(SMBH) within a thin circumbinarydisc, but Vivek produced new spec-troscopy suggesting a binary black holemay be ruled out. That same yearHeckman thought S J0927 could be ahigh redshift analog of NGC 1275, thecentral galaxy of Abell 426 in Perseus.The challenge to this idea was deeperimaging had not found the necessarysupporting rich cluster of galaxies sur-rounding S J0927, but only a moderate-

ly populated group at best.

In Komossa’s original study, thebroad emission lines associated withthe ejected black hole/quasar carried aredshift of 0.697, with the narrow emis-sion lines left behind from the originalmerging structure showing 0.712. Thisimplied a velocity difference of 2,650km/s, within the range of theory for“gravitational wave recoil”. In one mil-lion years, this would lead to a separa-tion of a few kiloparsecs between theobjects. She also felt the gas and dustaccompanying and surrounding theejected black hole were fueling itsenergy output, igniting the quasar. Inanalyzing the mass of this accretiondisc, she estimated its quasar activitycould last a billion years. The best fitfor the pre-merger event was betweentwo rapidly spinning black holes ofequal mass. This suggested what iscalled a “major merger”, where galax-ies of relatively equal size are involved,similar to the “Antennae” (NGC 4038-9), but unlike M51 whose companionNGC 5195 is of smaller size and mass.

By chance the location of S J0927 waswithin the X-ray fields of ROSAT from1994-5, which showed central AGNactivity defining an inner accretion discfor the quasar.

Blecha and Loeb suggested in 2008that “non-ejected” central SMBHs maywander about the new galaxy for a mil-lion to a billion years, and be detectableas a quasar offset from its center. In a2014 MNRAS paper Wang described apotential population of intermediatesize black holes (those between a fewhundred and a million solar masses),possibly floating in the Milky Way halofrom recoil events involving tripleblack hole interactions. In 2010 Decarliidentified a nearby quasar, only 17.5”,or 125 kpc, SE of S J0927, with a red-shift of 0.705 and a (g) mag of 19.18. Itwas thought to indicate these twoactive galactic nuclei were part of, andbeing fueled by, an evolving galaxygroup. Dense galaxy environments aretriggers for AGN activity, exemplifiedby the Seyfert 2 designation for NGC7319 in Stephan’s Quintet. In aJanuary, 2015 MNRAS paper Novak

The Telrad finder is centered at the location of J0927 - RA 09h 24m 15.0s and Declination -29d 56’ 37”The nearest bright galaxy is NGC 2907, which is 1.5 degrees away.

from the Harvard SmithsonianAstrophysical Observatory identifiedanother recoil candidate similar to SJ0927: a merged pair of SMBHs calledCID-42.

At the 2015 Texas Star Party I usedmy 32” f4 reflector to observe the fieldof SDSS J0927+2943 on May 13th, atabout 3 am. The object was well up inthe western sky, about 65 degreesabove the horizon, but conditions wereaverage at best in a week beset withhumidity and storms. Seeing wasunsettled and varying from moderatelypoor to occasionally very good, mak-ing us work hard for our sightings,picking moments of stability toattempt fainter and more challengingtargets. Using first a 9 mm eyepiecegiving 361X, and then a 5 mm to yield650X when conditions allowed, thefield 3.5 degrees NNE of the 4.5 magstar Kappa Leo, in the NW corner ofthe constellation was searched. Therewas a 14th mag star 2.6’ NNW of thequasar, and a pair of stars 3.7’ SE, thecloser one being brighter at 11th mag.Just 1’ east was a mag 15.5 star, and it

took several minutes to sight both the“recoiling SMBH” with a (g) magni-tude of 18.42, and its fainter (mag.19.18) companion quasar ~20” to itsSE, several times to be certain of theobservation. They were both stellar,and there was no sign of galaxies in thearea.

This inlaid gem in the sky’s mosaicis still a “candidate” for being the van-guard of its class of gravitational waverecoil objects, according toresearchers. The recommendations ofStephanie Komossa in her discoverypaper sound a prudent cautionary note:that significant follow up studies inmultiple wavelengths with Hubble,VLA and Chandra will be necessary toconfirm its nature. Ebb and flow ofdebate is the fulcrum of reflectionbetween observation and theory, andone day our persistent assaults maybreach a wall of ignorance.

Dave TostesonChisago City, [email protected]



Well before the telescope was inventedhumans saw that some sky objects hadstriking colours: for example Mars, or‘Ares’, was “fiery red” – as was thestar Antares. But the former movedabout the sky, brightening or fading,while the latter was fixed. At times theMoon would change to a ghastly red!It was all very puzzling!

By the 19th century astronomers wereusing florid language to describe stars,particularly doubles: “gold and azure”,“topaz and green” and “yellow andlilac” etc!

Basically, star colours vary from bluethrough white to yellow and orange.Red stars are actually rare, but doexist. One of the best is near (blue)Beta Crucis: the very ‘red’ star EB365is in the same field –use low power forthe best effect; it is spectral type C, arare ‘carbon’ star. And red star X in TriAus takes the breath away! It’s also acarbon star.

Colour contrasts can transform other-wise commonplace fields of view: afine example is the globular clusterN5286, or D388, first logged by

‘Jamie’ Dunlop c.1826 at Parramattaand sited some 2ºN of bright starEpsilon Cen.

N5286. Here we see (sketch) the less-er known globular cluster beside4.6mg “gold and blue” double star MCen: a very pretty field indeed!

The site was first sketched in Sydneyin 2011 - and when next viewed inNowra the globular had ‘grown’ some-what: presumably more of its ‘halo’ ofunresolved stars could now be seen indarker skies.

In visual appearance globulars canvary quite a bit; this one is no excep-tion, being irregular in shape: a roughpentagon, maybe. The faint outer haloof unresolved stars showed well at lowpower, but central details were bestseen in a 4.8Nagler. Even its faint cen-tral condensation is square-ish; partlyresolved chains of faint (<13mg) starscurve outward from its centre. Sourcessuggest an average member is magni-tude 14. Some darker ‘lanes’ may alsobe seen.

Website images of deep sky objects

seldom match the view in an eyepiece–as the eye cannot integrate light overtime and most photos of globulars areexposed until the full halo diameter isrecorded. Consult a photo and it’s clearI have recorded only some of the glob-ular’s faint halo.

Globular cluster members are of onlytwo spectral types: either type F(Canopus-like) or G (sun-like) yellowstars, i.e. they are mostly pale yellowstars with a few ‘blue stragglers’. Doblue globulars (i.e. type B stars) existin other galaxies? I am not sure - but inours, all globulars are dense clusters ofyellowish stars: as can be seen in47Tuc.

M Cen. The view of N5286 is enrichedby several field stars and particularlyby M Cen (Harvard double HdO 225):a richly coloured double star. The mainstar, a 4.6mag primary, is yellow-orange in hue, but sources disagree onits spectral type: it’s either G5 or gK0(g = giant) – i.e. it’s a sun-like yellowor an Aldebaran-like orange-yellow(looks orange to me.) Defocus the starslightly and its colour becomes clearer.Left (i.e. east) some 40arcsec from theprimary is the 11mg secondary. Itsspectral type is not stated but seemsblue-ish: a type B dwarf maybe. Doesit look blue to you?

This is a beautiful field for telescopesof almost any size, and small blueplanetary nebula N5307 lies just 6minutes east of the site.

Clear southern skies!

Harry

NGC 5286: Dunlap 388 and M CentaurusHarry Roberts


SpaceImages.comBUY beautiful Hubble NASA high quality astronomy spacepictures, posters, slides, and backlit transparencies fromouter space programs and spacecraft missions to the Moon,Mars, Jupiter, Saturn, and photos of the Earth from space.


The iOptron iPano versus Gigapan ShootoutDavid Lane

This article will compare the newiPano from iOptron to the indus-try standard Gigapan Epic Pro. I

used the Gigapan Pro for all of 2014and the early part of 2015. I used theiPano for 3 months in 2015 and haveseveral resulting images from each toshare.

I am giving an unbiased comparison ofthe two platforms here but I’m going tobe forthright and say I have a favorite.So expect that at times though I maywax somewhat poetic in descriptions,however certainly all of the informa-tion will be based in actual perform-ance.

The criteria I have chosen to rate thetwo platforms are: speed of operation,ease of menu options, battery life, qual-ity of construction and ability to adaptto other purposes, for example panningfor video or timelapse.

Let’s take a look at the Gigapan first.It’s the venerable first panorama plat-

form to achieve attention. I’m certainthat other platforms existed before, butlet’s just say Gigapan was a pioneer inthe field. The Gigapan Epic Pro is anelegant machine. Its menu options areeasy to follow and it has replaceablebatteries which is a big plus if you aregoing on an extended trip as. you cankeep one charging while the other oneis in use

At the time it was introduced theGigapan was a quality instrumentdesigned to do an excellent job of tak-

ing large daytime panoramas. I man-aged to use it to do night time starscapepanoramas but it took some time tobecome comfortable with its use. Oncethe learning curve had been conqueredit provided a reliable platform to takenight shots.

The biggest disadvantages for theGigapan are in two areas, quality ofbuild and battery life. The quality ofbuild is hard to express in words soyou might want to watch the videosI’ve produced. In general, the ability to

I decided to rank each aspect of the test on a 1-10 scale, the results of which I’velisted in the table below.

How they compared:iPano Gigapan

Speed of operation 10 7Ease of menu options 7* 9Battery life 10+ 5Quality of construction 10 7Other purposes 8 9Total score 45+ 39


remain motionless with wind, which isfar more important on long exposureimages, is dramatically worse than theiPano. Through a summer of shooting Igenerally lost 4-5 panos because of theissue, which isn’t that bad;, but I’d hateto lose that one great shot you mightget in a single evening’s shooting.

The other issue is battery life. Until Ihad the iPano to work with, I was finewith the battery life of the Gigapan.Shooting 4-5 16 image panoramas in anight left me with 25-30% of batteryremaining. The replaceable batterieswere helpful as you could limp throughthree nights of shooting without havingto access external power to chargethem. I was able to partially chargethem with a converter in the my vehi-cle. The time it took to fully rechargethe batteries on AC power was 4-8hours depending on the amount ofremaining charge.

On speed of operation the two plat-forms were consistent and although theGigapan was slower in its movementsit performed them effectively. The pre-cision and speed of motion clearly waslacking compared to the iPano.

Now let’s look at the iPano. There areseveral items with the iPano that arevery similar in design and several morewhere the iPano is clearly head andshoulders above the Gigapan. As can beexpected with a second generationdevice the iPano has improvements inseveral important areas.

First let’s look at battery life. Here Ihave to say my initial fears weredestroyed. I had initially been con-cerned by the lack of a removable bat-tery even though I was told the batterywould last 24 hours. I shouldn’t havebeen concerned in the least. Althoughon my first two trips I did recharge theiPano when I had a chance, the last tripin August, I decided to try an experi-ment for this article. I decided to notcharge the iPano the entire trip. I spentthe next 8 nights shooting with theiPano and it hadn’t even dropped to70% of charge. I was stunned. Evenmore stunning was when I set it backup in November to create the videos forthe article; it still had over 60% chargeleft after being last charged in July.Now that’s remarkable.

Quality of build is another area theiPano excelled. The iPano just felt solidand, it virtually snapped to the nextimage location with the precision of aSwiss watch. Again you may need tosee the videos to wholly understandthis. I could tell one was made by aconsumer camera manufacturer andone was made by an astronomy basedengineering company. Additionally, Ididn’t lose a single image to windshake and that’s saying a lot. This littleguy was one foot from a 3,000 footdrop with 20-30 mph winds pushing ittoward the abyss. No issue. Not onedropped or blurred image all summer.

The menu system on the two platformswas well, let’s just say they were very,very similar. One issue I ran into on theiPano was occasional confusing ver-biage. Pausing the iPano and thenrestarting it was tricky since theinstructions where oddly worded. I lostseveral partial panos during the sum-mer when I couldn’t remember whichbutton to press to continue. I shouldmention the iPano I received was a betaunit with beta firmware so I wouldexpect by now this would not be anissue.

There is one last comparison betweenthe two systems. The Gigapan and theiPano have a timelapse / panning capa-bility and it was hard to test them in thereal world for the difference in func-tions. I looked at other add-on hard-ware and software to access these fea-tures. While I couldn’t test the per-formance of these, the Gigapanappeared to have more developed for itas one would suspect. I therefore gaveit a slight nod on this feature..

From the tests it was obvious to me thatfrom an engineering standpoint theiPano was the superior platform. Thereare certainly reasons that may precludeone or the other depending on what youlook to accomplish. Both systems arecertainly capable of accomplishing thesame result.

ConclusionWhile both platforms are excellent forwhat they can do, the iPano is a clearwinner. The battery life is so robust it isa real advantage, giving me the abilityin remote locations to go withoutpower for several days at a time. The

engineering and build quality appearsto be superior as well.

If they are at were the same retail pricepoint I would see the iPano as a bettervalue. However, I would love to seeiOptron lower the price a bit to $895 oreven better $795. If they could do thisand preserve the quality of the unit thisunit should be everyone’s first choice.

This season of shooting I will be usingthe iPano as my primary platform, withthe Gigapan in reserve in case of somedisaster like the iPano ending up in thebottom of the Grand Canyon, whichsadly is a real possibility. Clear skieseveryone and never forget to look up.

*I received a beta unit with no manualand beta firmware in the unit. I imaginenew firmware would be improved andthat this the score I gave should rise.

Answers to NervoShaterinni Quiz

(1 ) -273 .15° (As i f . 15

makes any ~ difference! I t ' s

s t i l l cold!

(2) To Black Holes

(3) two

(4) towards us

(5) Vega is used as the s tan-

dard for Magnitude O.

(6) Crux, surpr is ingly is the

brightest Constel la t ion.

(7) Aries (Argo)

(8) There are 259,000 s tars

in the SAO Catalog.

(9) January

(10) Gionanni Ricciol i dis-

covered in 1650 that Mizar

had a te lescopic companion

star.

(12) 100,000 l ight years

(13) 100 eyes (14) St . Kevin

(15) about 8 minutes

(16) Mt. Stromlo

(17) Mauna Kea in Hawaii

(18) Bi l l Bradfield

(19) Ursa Major

(20) Hydrus


This discussion is based on theauthor's rudimentary knowledgeand meditations while, as this

publication suggests, an amateurastronomer and not a trained physicist.It is offered with respect to theprogress of physicists and all that theydo as the source of inspiration for theseconsiderations. Their approach to thedevelopment and stewardship ofknowledge is sound. And, to Einsteinand Feynman, we are but a small specin the last row of the audience of theirshow. C'est la vie.

Developing Knowledge

To praise the methodology of physi-cists regarding knowledge is right andproper. This is worth some explana-tion. This is comparing and contrast-ing with social sciences and, mostspecifically, with sociology and educa-tion. Psychology, for example, proba-bly does a great deal better in terms offollowing the Socratic method andensuring some integrity in what isthought to be truths and foundationalprinciples, etc. Education must surelybe the worst to which this author, ateacher educator of 30 years, canattest. Many educators think theyknow things, that they have discoveredthe nature of learning and the method-ologies for teaching and the manageri-al principles for carrying out that mis-sion. Yet, in fact, they barely have anever-fluctuating set of guesses, fads,notions and ideological superstitions.For example, Mastery Learning israrely mentioned today but was com-monplace in the halls of teacher educa-tion only a couple decades ago. It ispresumably passé in favor of new andimproved ideas yet the product of edu-cation remains unimproved. Theresult, instead of a steadily growingand strengthening process of learningfor America's youth, is an ever-fluctu-ating level and even deterioration ofeducational progress and waningexpertise.

Physics, however, has steadily pro-gressed for hundreds of years.Knowledge has positively increasedand the advancements of key physi-cists are well-documented. Mainly,they ask questions. They ask questionswithout the presumption of ignoranceor the fear of reprisal for challengingestablished ideas. I'm speaking ofmodern times rather than the rebel for-titude of Galileo and price he had topay to expand our knowledge.Physicists explore and share their ideasand work to develop theories some ofwhich may seem impossible to many.Feynman has written of the casualforums in which he and others sharedand challenged their ideas. They workto build on what had been establishedin earlier generations. But, with theo-ries tested and experiments recorded,new knowledge can evolve incremen-tally as the discipline of physics hasproven many times over.

Education, by contrast, cycles througha seemingly endless series of fads,trends and fashions - unproven notionsperpetuated by the superstitious, unsci-entific and biased practitioners. Thischarge is based on the author's person-al experience at several universitieswherein they no longer ask real ques-tions, maintain inquiring minds andinstead profess an unwarranted confi-dence and self-assurance. Yet,American education yields an everlower literacy rate, loss of standingcompared with other countries and anincreasing population of Americanyouth who know nothing of their owncountry, culture and history. All thiseven in the face of professionals whoclaim greater understanding of learn-ing and greater confidence in theirmethods. Physics, as a discipline, andscience in general, provide a moreclassic and infinitely more soundmodel of how knowledge can bedeveloped. It is critical to continue toask questions and recognize howsomething is unknown and often how

something might not be knowablegiven the proofs available.

Physics

The many years have provided a fairlysubstantial understanding of threeforces in nature. Furthermore, it isalso known that the three forcesexplain everything with the exceptionof gravity - which remains elusive.One of the primary quests in physics,therefore, is to find a particle or a tan-gible component of gravitational forcethat would complete and hopefullyunify the understanding of nature'sforces.

One explanation of the function ofgravity is through particles - subatom-ic particles - that serve as the commu-nication of gravitational force fromone object to another. That is, theattraction of one objection (B) byanother (A) is applied as A sends a par-ticle - a graviton (perhaps) - to B tosomehow draw upon it, to pull it, toattract it in some fashion so a gravita-tional attraction is realized. Whetherthe so-called "God" particle is in factthis singular element of gravity orsome other unifying sub-atomic ele-ment is a preoccupation of physicists.Apparently, it is elusive, mystical, and,in any event, still completely hidden asno one has yet discovered any trace ofit.

The Three Forces

The three forces that are identifiedinclude the Weak Nuclear Force. Theweak force, while it seems to be fairlywell understood among physicists andseems particularly mystifying in itself.The forces of nuclear fission, atomicparticle decay (like the loss of neutronsfrom a heavy element such as Uranium235) are governed by the weak nuclearforce.

On the other hand, the Strong Nuclear

Gravity Does Not ExistDr. Jerry Galloway

Professor of Education, Retired


Force seems more intuitive and evenself-evident. The constituent parts ofan atom, for example, - the protons andneutrons - do in fact hold together.They do bind together and the StrongForce keeps them together. Therewould be no building blocks of the uni-verse without them. The hydrogenatom could not exist without the StrongForce that binds even the singular pro-ton and neutron together. High speedparticle accelerators - super colliders -have smashed these tiny atomic piecesto find the smaller sub-atomic particlesand explore the forces that make themwhat they are.

Electromagnetism includes the interac-tion of charged particles - electrical andmagnetic forces - making up the 3rd ofthe known forces of nature. It worksacross both long and short distancesand includes electrons, photons, etc.Light and heat are phenomena of elec-tromagnetic energy and seems to me tobe the most tangible and corporeal ofthe three forces. Shining a flashlight,watching television, talking on a phoneor just seeing a sunny day all provideobvious examples of the electromag-netic force.

Gravity

Gravity is, for physicists, the elusive"force." It is in quotes because it is notentirely certain that it is in fact a force,per se. They have not discovered agraviton. They have not found a gravi-tational particle - that thing which pre-sumably conveys to object B that it isto be attracted to object A.

Nevertheless, a phenomenon obviously

exists. The old fable of an apple fallingon Isaac Newton to spawn the discov-ery of gravity is something we experi-ence every day. Certainly, gravity - asa phenomenon - does exist. We are

held to the Earth which is, in turn, heldto the Sun, none of which go flying offin to space to find new random paths.

Gravity has been described as a forceacross distance. This is, object A mustpresumably convey in some manner,must communicate in some way acrossdistance to reach object B that it is to beattracted to and drawn back to object A.How does the Sun communicate to theEarth that it is to stay close by and notgo off on its own? What is the natureof and energy level of that force suchthat it seems to balance perfectly theinertial tendency of the Earth to contin-ue outward along a straight line leavingthe solar system behind? Of course,that same phenomenon plays itself outwith Pluto, Haley's comet and all theother parts of the solar system just asthe Sun is held within the grasp of theMilky Way galaxy.

One must also understand that the grav-itational force - the gravitational"effect" - is shared between the twoobjects, A and B. That is, not only doesthe Sun attract the Earth but the Earthattracts the Sun. In fact, an orbitingplanet can and does make the host starwobble or shudder to balance the massof the two bodies. The star is not a per-fect, unwavering anchor around whicha planet travels. Instead, the twotogether, bound by gravity (whateverthat is), act as a single unit both travel-ing around each other. It is, of course,severely lopsided as the huge mass ofthe star far exceeds the relatively lightweight planetary object. So, the starhas a small wobble while the planetswings widely around the large mass.But, the total mass of the two objectsbalance around a focal point aroundwhich both objects move.

So, what holds them together? That'swhere the concept of a force comes inand, in physics, the notion of a commu-nicating particle through which thatforce is applied (or carried). One mightimagine a kind of test case - a simpli-fied model. Imagine a universe inwhich only one single object exists. Itsits, or floats, serenely in a kind of sta-tionary existence unaffected by anyoutside force. Now add another objectinto that universe, perhaps at some dis-tance away. Gravity suggests that bothof the objects will be disturbed by theexistence of the other. Both object, Aand B, will be attracted to each otherboth affected by a mutual gravitationalpull.

Continued page 26

Illustrations representing the weak force (left) versus the strong force middle) and E-force (right)


The Graviton

While the big question is about howthis works or by what mechanism suchattraction is executed, it must occuracross a distance. Regardless of thedistance, whether 1 mile or a thousandlight years, the distance must some-how be covered or transversed by thatmechanism. That mechanism is com-monly thought to be a graviton - a the-oretical particle of gravity.

But, since nothing can move fasterthan light, it suggests that gravity can-not affect things at a distance soonerthan the time that might be travelled bylight. Knowing, for example, that lightcan take thousands of years to reach usfrom distant stars, it suggests that, if agiven star were suddenly to cease toexist, it would not affect us gravita-tionally for perhaps thousands ofyears. Even on our own smaller scale,being 8 minutes from our own star, itsuggests that we are affected - pulledor attracted - always with an 8 minutedelay.

In our sample model, with A and B asthe only two objects in the universe at1 light year apart, it would stand to rea-son that adding the second object Binto the universe would leave object Aundisturbed for a full year at the least.In spite of the logic, this seems count-er-intuitive to how the universe works.

One can further explore this model ofinteraction. For example, how doesobject A know where object B is locat-ed in order to communicate directlyand specifically with it? The notion ofa force using particle communicationseems to presume that such particlesare continually and perpetually emittedin all possible directions so that onecoincidental path happens upon thenew arrival, object B, to execute thegravitational attraction. This tooseems counter-intuitive.

We know that objects can and do existfor billions of years. Consider thatobject A might be alone in our imagi-nary universe, undisturbed and serene-ly waiting for 10 billion years beforethe arrival of object B, one light yearaway. So, the particle communication

concept - gravitational force at a dis-tance - suggests that object A is emit-ting gravitons (for lack of a betterterm) in all possible directions 3dimensionally, continuously for 10 bil-lion years before finding the newarrival of object B.

This suggests that object A has a virtu-ally unlimited supply of gravitons,assuming such gravity particles exist.How many gravitons must reach objectB in order to be effective? One? Isthere a difference in the gravitationalattraction when an object receives bil-lions of gravitons from its caller versusmerely receiving one? Even withoutconsidering the dissipation, disburse-ment and thinning of such emissionsover distance, this unlimited supplyand continual emission in all possibledirections virtually forever all seemcounter-intuitive as well.

Alternative Gravity

This paper suggests instead that thereis no graviton. There is essentially nosuch thing as gravity in that traditionalsense. Gravity is not a force, per se. Itwill not be discovered in the tradition-al sense. There is no elusive particlewaiting to be found.

This does not at all suggest that there isno "God" particle, something thatwould unify all of the forces into onecohesive theory of nature. Like E-MC2 has an elegance in that it capturesand represents the general theory ofrelativity, such a singular representa-tion of the forces of nature is desiredand sought. Such a unification mayexist and a discovery may yet be made.But, it will not include gravity wheregravity is not one of the forces. In thatsense, gravity does not exist.

But, of course, the phenomenon ofgravity certainly does exist. Droppinga pencil, it will surely hit the floor.Loosing forward thrust in a plane willcertainly bring you back downinevitably to land or crash. Everyonehas experienced the difficulty liftingand carrying heavy loads. One maystep onto the scales daily to apply anumeric quantification to dietaryexcess. Science can help one developnew lighter-weight materials withoutsacrificing structural integrity. Theplanet really does continue to orbit ourstar which remains a faithful memberof the Milky Way.

So, what is this thing called gravity ifnot a "force" in the usual particle com-munication sense? This paper sug-gests that the universe is a kind of con-tainer. A box? A bag? A large vat? Itseems impossible to suggest a propermetaphor that fairly represents theenormity and the flexibility of the realthing. But, it is suggested that the uni-verse, as a container, has a characterabout it. That it is a real thing as com-pared to a non-existent thing or a noth-ingness.

Space is often described as emptyexcept where objects exist. Space isoften described as a lot of nothingnessin which there are a lot of things - plan-ets, stars, rocks, etc. But, the commonnotion is that space itself is a kind ofnothingness. It is suggested that it isnot a nothingness; that it is, instead, areal container and has a kind of char-acter about it. Of course, the full char-acter or nature of space itself is not atall well-understood and therein lies yetanother quest for physics.

But, it is also suggested that space ispliable, flexible, even malleable. Itresponds to the presence of mass. Thatis, mass - any mass - will bend orshape space to accommodate its pres-ence in the container. Even the theoryof general relativity suggests a curva-ture of space-time around mass - thatthe structure of space is not uniformand constant and indeed curves aroundobjects.

This should not be particularly confus-ing and, indeed, seems to be more intu-


itively comfortable than the emissionand receipt of graviton particles com-municating the mechanism of attrac-tion. A useful analogy - admittedlyweak at best - is that of a large swim-ming pool filled with water. The uni-verse (the 3 dimensional body of water)contains a single ball floating at oneend of the pool (object A). In theabsence of wind or other seismic influ-ence, the water is serine and the ball isundisturbed. Adding a ball of somelarge mass into the water at the oppo-site end of the pool will naturally causethe water to rise. The first ball (A) nat-urally rises with the water level. This isnot because object B (the large massball) sends a message to the first ball.Object A (the first ball) is affectedbecause the container itself is affected.The body of water itself now has aslightly different shape, a differentdimension, and the first ball "rides" inthat evolving dimension.

Another analogy, which has been sug-gested often, is more 2 dimensional butserves well-enough. Imagine a kind ofrubber sheet suspended above theground. Placing a steel ball on thesheet will naturally cause a depression.The heavy mass bends and shapes thesheet and bends it around the ball.Attempting to roll a marble or some-thing in a straight light will find it curv-ing around the depression caused bythe first heavy ball. It is a natural cur-vature in the rubber sheet which acts asthe container - the universe - for thetwo balls.

In our imaginary two-object universesuggested earlier, object A does indeedbend and shape the universe containerto accommodate its own existence notunlike the 2 dimensional rubber sheet.But, until object B is added, it remainsundisturbed content in its own equilib-rium - its own unchanging universe.Once object B is added, even one lightyear away, object A is indeed disturbed.But, it is disturbed immediately notwaiting for communication at a dis-tance. It is disturbed because the con-tainer itself has changed. Like thewater in the pool, planet A rides alongon the slope or curve of its universecontainer. Like adding a second ballbearing to the rubber sheet, the first

will roll down along its 2 dimensionalslope toward the second.

To continue the rubber sheet analogy,the two ball bearings roll toward eachother not because they are attracted toeach other by magnetism or gravitonsor any other communication butbecause the shape of their containerdemands it. Indeed, if there were athird even larger and heavier object onthe rubber sheet both objects A and Bwould roll toward the larger object C asits mass has caused an even greaterdepression, a larger disruption in theotherwise uniform container. It is areshaping of the container.

It is not a difficult notion to conceive,that it is the shape and character of theuniverse itself that creates gravitationalphenomena. That is, we are not attract-ed to the earth by gravity where the twomasses involved, my body and theplanet, each emit graviton particlescommunicating an attraction for eachto pull together. Instead, we are essen-tially falling into the 3 dimensionaldepression caused by the great mass ofthe earth in our otherwise uniform con-tainer.

The space around us - the universe inour local region - has a lot of depres-sions in it caused by all sorts of objects.From the Sun to each individual planetalong with every asteroid or tiny spacerock, each object disturbs the surface orcharacter of the space around it creat-

ing a kind of 3 dimensional depressioninto which all other things are drawn.Each object creates a disturbance con-sistent with its mass which dissipates toever smaller degrees over distancewithout ever disappearing completely.

There are no gravitons communicatinganything nor being emitted andreceived anywhere. Gravity in thatsense is not a force. It is not a particle.It does not exist in that sense. Gravityis an experience of the deformity ofspace - our universe container - causedby and correlated directly with themass it contains. So, gravity is not aforce, it is just the shape of the contain-er.


Lunar Sketchbook: SchillerHarry Roberts

Schiller is one of the strangest forma-tions on the Moon! Located near thelunar SW limb, it is best seen as thelunar phase approaches full, or at lastquarter (in early morning). At dusk onjune 11, 2003 I had a nice view in the4” maksutov and set up the C8 for adetailed drawing (Fig).

As often happens, dramatic shadowsacross the crater floor drew the eye toa speck of sunlight on one of the linearcentral peaks at the northern (left) endof the formation: shadow filled muchof the north half of Schiller. It wastricky to sketch since on this date theterrestrial E-W line of drift (one axis ofthe drawing) lay almost along the for-mation’s centre. This E-W line movesaround a lot relative to lunar longitudedue to the moon’s complex orbitalmotion. In addition, Schiller’s prox-imity to the lunar limb increased its

cigar shape – the whole formationcrosses some 6 degrees of lunar longi-tude and five of latitude.

Schiller is 180 km long and 71 km atthe widest. Lunar curvature helped toelongate rim shadows at the northernend. Yet the shadow cast by the east-ern rim diminished to zero in the vicin-ity of crater H (Fig), an odd shapedcrater: maybe two superimposed.Presumably H ‘punched’ a gap in therim wall almost to floor level.Schiller’s rim must be very high northof H, to cause such long shadows: 4kmmaybe?

At Schiller’s southern (right) end lies adetached medium sized crater (RostB?) co-axial with the main formation–connected by a shallow valley itseems? Not labelled in Rukl’s “Atlasof the Moon” – “Virtual Moon” free-ware suggests it’s Rost B: Rost is outof the field to the south.

Schiller’s brightly lit inner westernwall showed terraces and other slip-page features, and cast long shadowstowards the lunar terminator. I loggedthree tiny craters on Schiller’s smoothfloor in the good seeing: their diame-ters are between two to three kms.Interestingly Schiller contains two lin-ear central ranges at the northern endof the formation; one seen clearly, theother a speck of light; as well there issome uneven ground and slippagematerial from the high scarps on thenorthern floor.

Formation? The big puzzle aboutSchiller is to explain how the forma-tion was created. Wood tells us“Impact craters are round because theyare essentially point source explosionsthat throw material out in all direc-tions. So what is wrong with Schiller, astructure 180km long but only ~70kmwide? A clue comes from the centralridge at the upper (NW) end of thestructure and the coalescence of multi-

Sketching the MoonHarry Roberts


ple craters. Similar features are seen invery low angle oblique impacts createdin NASA’s labs”. He adds “Perhaps asmall asteroid or comet was capturedinto lunar orbit and while spirallinginward, was torn into pieces...creatingoverlapping craters”. Kaguya LunarAtlas. 2011. P132.

The main part of the northern end ofSchiller has almost parallel crater wallswith the long, linear central ridges.David Gault’s impact experiments(Fig) showed how such craters resultfrom very low angle impacts that createalmost ‘linear’ explosions. TheSchiller impacts must have been at avery low angle: like Gault’s 2 or 3degree results.

There are much smaller formations ofthis kind on the moon, particularlyparts of the “Rheita Valley” in the lunarSE, and the Messier craters in M.Fecunditatis. As we have now seenmultiple comet impacts on Jupiter – the

multi-impact idea no longer seems asimplausible as it did before 1994.

Schiller [51.8°S, 40.0°W] was JuliusSchiller, d. 1627. A German monk.Author of an atlas of the sky, in whichthe constellations were replaced by bib-lical characters and objects. His systemwas not adopted. Crater Schiller is avery odd ‘creature’: unique on theMoon. Take a close look when themoon’s phase next approaches full.Clear skies.


July 8-10 Connecticut River Valley AstronomersConjunction 2016

Northfield Mtn Recreation area, MAhttp://www.philharrington.net/astroconjunction/

July 30-Aug 7 Mount Kobau Star Party 2016Mt Kobau, Kelowna, British Columbia, Canadahttp://www.mksp.ca/

July 31 – Aug 5 The Nebraska Star Party 2016Merritt Reserve (Snake Campground) near Valentine, NEhttp://www.nebraskastarparty.org/

Aug 2-6 Table Mountain Star Party 2016Eden Valley Guest Ranch, Oroville, WAhttp://www.tmspa.com/

Aug 2-7Oregon Star Party 2016Indian Trail Spring + Ochoco National Foresthttp://oregonstarparty.org

Aug 4-7 Stellafane 2016Breezy Hill, Springfield, VThttp://stellafane.org/

August 4-7 Starfest 2016River Place Park, Ayton, Ontario, Canadahttp://www.nyaa.ca/

August 22-27 SolarFest USA 201635 acre ICSTARS rand 1 hour east of Kansas Cityhttp://www.solarfestusa.com

Aug 27 – Sept 4 Merritt Star Quest – 2016Quilchena Ranch - Merritt, BC, Canadahttp://www.merrittastronomical.com/

Aug 31 – Sept 3 Northern Nights Star Fest 2016Long Lake Conservation Center, Palisade, MNhttp://www.mnastro.org/northern-nights-star-fest/

Aug 31 – Sept 5 Brothers Star Party 2016Brothers, OR, 42 miles east of Bend Oregonhttp://www.mbsp.org/

Sept 2 - 6 Almost Heaven Star Party 2016Hobbs Observatory, 4 miles North of Fall Creek Wisconsinhttp://www.ahsp.org

Sept 2-4 Black Forest Star Party 2016Cherry Springs State Park, near Cloudsport, PAhttp://bfsp.org/

Sept 24 – Oct 2 Okie Tex Star Party – 2016Camp Billy Joe - Kenton, Oklahomahttp://www.okie-tex.com/

Star Party & Astronomical Event CalendarStar Party & Astronomical Event CalendarJ u l y 2 0 1 6 - O c t o b e r 2 0 1 6


Sept 29-Oct 1 Illinois Dark Skies Star Party 2016Jim Edgar Panther Creek State Fish and Wildlife PreserveNear Springfield, ILhttp://sas-sky.org/

Sept 29 – Oct 2 The Heart of America Star Party 2016ASKC dark site near the Marais des Cynes River, Kansas

http://hoasp.org/

Sept 30 - Oct 1 Idaho Star Party – 2016Bruneau Dunes State Park, Idahohttp://isp.boiseastro.org/

Sept 30 – Oct 2 Connecticut Star Party 2016Ashford, CThttp://www.asnh.org/

Sept 30-Oct 1 Astroassembly 2016Seagrave Memorial Observatory, N. Scituate RIhttp://www.theskyscrapers.org/

October 15 ScopeX Telescope and Astronomy Expo Saxonwold, South Africahttp://www.scopex.co.za/

Oct 24-29 Eldorado Star Party 20167,100 acre X-Bar Ranch near Eldorado, Texashttp://eldoradostarparty.org/

Oct 26-29 Enchanted Skies Star Party 2016 Magdalena, NM http://enchantedskies.org/

Oct 23-30 Chiefland (CSPG) Fall Star Party 2016Chiefland Astronomy Village, Chiefland FLwww.chieflandastronomy.com

Don’t see your local, or favorite Star Party listed here? Ifyou run or attend a star party that is not listed, and wouldlike us to do so, send information to [email protected].


Tycho crater is a feature the lunarnovice falls in love with and stillretains an affection for after they

become experienced Moon observers.Tycho was named after the 16th centu-ry Danish astronomer Tycho Braheand is one of the finest examples of acomplex crater on the near side of the

Moon. At 87 kilometers across, thismagnificent crater spans an area equalto the largest metropolitan cities anddisplays a central peak, flat floor, ter-raced walls, and secondary craters.

By far, Tycho's most fascinating fea-ture is the spectacular ray patternsplashing 3,000 kilometers across the

Moon’s face. The massive breadth ofthe Tychonian ray system is demon-strated by the rogue ray that streaksacross the smooth plains of MareSerenitatis 2000 kilometers northwestof ray's source. Tycho was created byan oblique impact of a projectile arriv-ing from the west, thus the crater's

Iconic Tycho Surrounded by Mystery!Images and text by Robert Reeves

Focus on the Moon with Robert Reeves

An enduring mystery is why some of the prominent Tychonian ray streamers do not align with the center ofTycho crater. The parallel northwestern streamers intersect on opposite sides of Tycho's walls while the singu-lar southwestern streamer is tangential to Tycho's rim.


ejecta and ray structure streams prima-rily to the east while the western regionremains noticeably smoother and ray-free.

Tycho is noticeably fresher and moreangular appearing than its neighboringcraters. Analysis of lunar samplesreturned by Apollo 17 date the Tychoimpact at 108 million years ago, mak-ing it the youngest major crater on theMoon. Tycho's flat floor was createdby impact shock melting of lunar mate-rial. Mountainous territory created byejecta thrown from the interior ofTycho extends for 100 kilometersbeyond the crater rim. Beyond theejecta blanket lie fields and strings ofsecondary craters giving the territoryan almost rust-pitted appearance.

A view of the Tycho region near fullmoon reveals two unusual facets aboutthe Tychonian ray system. The first isa dark donut surrounding bright Tycho.This is a zone of exclusion where theexplosion that excavated Tycho threwejecta and ray material up and over thisregion. The material did not fall backto the ground until about one craterdiameter beyond Tycho's rim. Withinthe donut there are almost no secondarycraters or pulverized particles of raymaterial, but beyond there are swarmsof secondaries and bright ray stream-ers. The dark donut is not obvious untilnear full moon. This is because thelight falling on the glassy particles thatmake the ray system reflects primarilytoward its source, the sun. Near thetime of full moon, the earth is alignedbetween the Moon and the sun, thusTycho's rough interior and ray systemreflect brightly and contrast against theless churned territory around the craterrim.

As shown in the feature photo at left,Tycho's expansive ray structure is hardto detect when close to the crater. Thisholds true with many rayed craters; thecloser you are, the less obvious therays. In fact, an astronaut standing on

the lunar surface within a bright craterray would not be aware of its existence.

The second unusual point about theTychonian ray system is not all thebright ray streamers converge to samefoci at Tycho's center. Indeed, theprominent southwestern ray is tangen-tial to the rim of Tycho. The famedparallel “railroad tracks”, twin raystreamers extending northwest, also donot converge at Tycho's center. Theseunexplained oddities force the questionof whether Tycho was created by astring of multiple impacts, the earlyimpacts creating the offset ray systemwhile the last impact overlaid the earli-

er impacts and created present dayTycho. It is fun to ponder such a sce-nario, but the true reason for Tycho'soffset rays is still unknown.

A study of the Baptistina family ofasteroids suggests that projectiles fromthis series were responsible for both theTycho impact and the later Earthimpact that created the Chicxulubcrater in the Yucatan 65 million yearsago. Though a connection between thetwo impact events is not proven, it isfascinating to contemplate that the cre-ation of Tycho may be related to theYucatan event that altered the evolu-tionary path of life on earth.

Tycho crater can not be seen withthe naked eye, but at full moon evi-dence of its existence is seen by theconvergence of the extensive raysystem which focuses on Tycho'slocation.

Feature image: Page 33: A close view of Tycho reveals of hundreds oftiny secondary craters extending primarily to the north and east. Notethe twin chains of secondaries extending to the upper left that align withthe parallel “railroad track” rays extending northwest from Tycho. Ahalf a dozen preexisting craters near Tycho were almost obliterated andhidden by the blast that excavated Tycho crater about 108 million yearsago.


Deep Sky Treasures

Seeing Dark In The Dark Observer’s Notebook

By John DavisNotes from Arunah HillOver the years in our summer DSTcolumns we’ve often discussed thebeauty and majesty of the Milky Way,and the advantage for the observer tobe viewing under a dark, transparentsky to fully appreciate and get the mostfrom the experience. Of course themajority of our targets, the clusters andnebulae, lie in the plane of our galaxy,the Milky Way. Those very dark trans-parent conditions are especially impor-tant when the objects we’re trying toobserve are dark nebulae, those

obscuring clouds of gas and dust.Because they are dark, in order to beseen they need to “stand out” against abrighter background of either somestars, like the myriad stars of the MilkyWay, or less frequently, against the gasand dust clouds of bright nebulae.

Today our appreciation of what we seeand enjoy observing dark nebulae canbe attributed to one seminal event, anaccomplishment that took place over100 years ago in 1905. It was the pio-neering photographic work of anAmerican astronomer and the greatestvisual observer of his time, Edward

Emerson Barnard. Barnard was born in1857, fatherless, into desperate povertyin Nashville, Tennessee. He hadacquired only two months of schoolingwhen, at the age of nine, he startedworking at a photographic lab and stu-dio to support his family. Over the 17years he worked there, and with dili-gence and hard work, he became anexpert in optics and those early photo-graphic techniques using glass plates.As a youth he became fascinated withastronomy and observing the stars. Heused much of his hard earned savings,$380, to purchase a 5-inch refractortelescope, with which he discovered

Intergalactic dust clouds obscure our view of the center of our Milky Way galaxy, but present fascinating objects in theirown right. This mosaic image was taken at the 2015 Texas Star Party with a Canon 60Da and Sky-Watcher StarAdventurer- Charlie Warren


several comets, each one earning himcash rewards offered at the time. Somuch did his reputation grow throughhis comet and other visual discoveriesthat he was given a student and teach-ing fellowship at VanderbiltUniversity. Eventually, his accomplish-ments led to his securing an appoint-ment in 1888 as staff astronomer at thenewly established Lick Observatory incentral California. There he continuedto build his reputation not only in widefield photography of the heavens, butin discovering more comets and inother very significant visual discover-ies, some with the Lick 36-inch refrac-tor, then the world’s largest. One in1892 was his discovery of the fifthmoon of Jupiter, Amalthea. In fact,Barnard’s remarkable discoveries,including one hundred fifty IC andNGC objects resonate even to the pres-ent day. They include NGC-6822“Barnard’s Galaxy” (discovered visu-ally in 1884 with a 5˜ refractor inNashville), NGC-281 in Cassiopeia(today’s “PacMan” nebula), the“California Nebula” NGC-1499 inPerseus, “Barnard’s Loop” a huge

faint supernova remnant in Orion andof course, “Barnard’s Star” the“Runaway”, a 9th mag. high propermotion red dwarf star in Ophiuchus,“streaking” along at over 10 arc sec-onds per year. Those were just a veryfew.

In 1895 Barnard moved to YerkesObservatory in Wisconsin, where hecontinued his work, primarily in photo-graphing the Milky Way, in particularthose mysterious dark blotches sprin-kled across its path. He now had theworld’s largest 40-inch Yerkes refrac-tor at his disposal and his new 10-inchwide field photographic BruceTelescope, donated by a wealthypatron. But the climate and especiallythe transparency and seeing conditionsin Wisconsin couldn’t match thoseexcellent conditions Barnard hadenjoyed in California. Fortunately, hisboss at Yerkes, George Ellery Hale,was now in California busily at workon the new Mt. Wilson Observatory,and arranged for Barnard to come toMt. Wilson along with the Bruce tele-scope where in January 1905, often

alone on the mountain, Barnard beganhis 9-month “marathon,” taking nearly500 photographs of the Milky Way.Though funds for publication had beenguaranteed, over the following yearsBarnard carefully inspected thousandsof prints and wrote descriptions for hisphotographs. His painstaking effortsfinally resulted in his crowningachievement, the acclaimed“Photographic Atlas of SelectedRegions of the Milky Way.”

This monumental work was publishedposthumously in 1927 by the CarnegieInstitution four years after Barnard’sdeath in 1923. Only 700 copies wereprinted. Forty of the fifty fields fea-tured in the atlas were taken in 1905 atMt. Wilson.

Like the Herschels and many otherastronomers of his day, Barnard hadinitially considered the dark nebulae,those inky patches encountered alongthe Milky Way, to be voids or “holes”in space where no stars existed, but asboth his photographic and visual obser-vations continued, especially after

Charlie Warren


C Warren


1905, he gradually came to the conclu-sion that it was very likely that thosedark patches were indeed great cloudsof dark material in space obscuring thestars beyond. His groundbreakingdetailed photographs convinced othersas well, even before modern astrophys-ical methods proved him correct.

Now let’s take a look at a very few ofthe many dark nebulae that populateour Milky Way. To start, we’ll take alook at two or three of the larger bod-ies of obscuring matter that contributeto its patchiness. If you look up andscan with binoculars between brightDeneb in Cygnus and the southern endof the rather dim constellationCepheus, you’ll see a dark “bay” about7 degrees across intruding into theMilky Way from the NNW. It’s calledLe Gentile 3 after the Frenchman whocatalogued it “way back” about 1750.Now look to the other side of Denebwhere you should see another darkarea, also about 7˚ across nestled in apocket between Deneb and g Cyg(Sadr), and e Cyg, 10˚ S of Deneb.Dubbed the “Northern Coalsack,”this dark pocket “stands out” betweenthe very bright areas of the nebulosityto the W around Sadr and the “NorthAmerica Nebula” on the NE.

You’ll also notice a narrow “exten-sion” from the Northern Coalsackforming a dark lane running on the SEin Cygnus along the “neck” of theSwan. This dark lane widens into the“Great Rift” in the Milky Way, clearlyseen on a dark transparent night run-

ning SW from Cygnus, past Aquila toits SE as it widens slightly, passing intoSerpens Cauda and Ophiuchus andleaving a separated bright “arm” of theMilky Way to its NW.

Now we’ll swing back to Cygnus, andto a spot 9˚ WNW of Deneb, the bright

Image courtesy Alan Dyer - amazingsky.com

In this narrowband image of M-17 - The Swan nebula, you can see areaswhere dark nebula obscure emission nebula, particularly in the areaunder the swan’s neck - Image by Charlie Warren


coarse open cluster M-39. Just under4˚ to the ESE of M-39 lies the veryfaint Cocoon Nebula, IC-5146. Youmay not be able to see this low surfacebrightness emission nebula without

some aperture: perhaps a 10˜ – 12˜scope with a narrowband filter like theH-Beta. You will, however, be able totrace with binoculars B-168, a darknarrow path to the Cocoon some 2

degrees long. Start at M-39 and scancarefully toward the ESE. Less than 2˚along the way you’ll pick up B-168,this dark Nebula. It stands out verywell against a very rich part of the

B92 & B93 - Charlie Warren

Starry Night Chart Detail


Milky Way, and shows up clearly in 10X 50 binoculars.

Next, we’ll slide down along the MilkyWay to Aquila and to mag. 2.6 Tarazed(g Aql) just 2˚ NNW of Altair. Nowscan from Tarazed less than 11/2˚ to theW and slightly N of W to find“Barnard’s E” (image page 37) a“fun” object – a dark capital “E” visiblein binoculars and especially largebinocs mounted on a tripod. B-142 isthe south prong of the E, while B-143denotes the middle and upper prongs.This beauty is also labeled the “TripleCave” in S&T’s “Pocket Sky Atlas”and again, stands out very well againstthe Milky Way.

Moving down the plane of our galaxyinto northern Sagittarius we’ll come tothe “showcase” M-17, the “OmegaNebula,” better known, perhaps, as the“Swan” which it truly resembles. If youexamine the Swan with a scope atmedium to high power, concentratingyour attention to the Swan’s curvedneck and head on the W, you may makeout an inky void of darkness just“under” the “head and beak” or to theW of the Swan’s crooked neck. This isa good example of dark obscuring neb-ulosity imposed upon a bright emissionnebula (image page 37).

Now we’ll swing SSW from M-17 just3˚ along the Milky Way to find our-selves centered on M-24, the magnifi-cent Small Sagittarius Star Cloud.Stretching almost 3˚ NNE-SSW, M-24

is a glorious sight in almost any scopeor binocs, especially a “rich field”scope or “giant” binoculars. Thousandsof stars will greet your view in a largerscope, including an embedded true starcluster NGC-6603. Back again in lowpower or large binocs, scan the NWedge of the star cloud and you’ll seetwo very prominent dark “notches.”The more easterly of the two isBarnard 93, a narrow dark slot, whilejust to its W is the larger dark oval des-ignated Barnard 92. In a scope try tospot the foreground 12th mag. star inthe center of B-92. You’ll also want toscan the NE end, as well as the SE sideof the star cloud for more indentationsof bordering dark nebulae.

If you have a very dark transparentPipe Nebula - C Warren


night, with the naked eye try to care-fully scan your gaze down into theGreat Sagittarius Star Cloud, thenswing across to the right or WNW andlook 10˚ below 2nd mag. Sabik (EtaOph) to locate 3rd mag. ThetaOphiuchi in a NE–SW line of some-what fainter stars. Just below this lineof stars, on a good night, you should beable to make out a 7˚ long horizontaldark lane with a large dark oval blos-soming on its eastern end. (Try it alsowith binoculars.) You have just foundthe “Pipe Nebula,” LDN-1773 (alsoB-65 – B-67), with the narrow “stem”on the right, and to the left the darkoval representing the Pipe’s “bowl.”The Pipe Nebula also represents thehindquarters of what is called the“Dark Horse,” a less obvious collec-tion of dark patches of nebulae withseveral Barnard numbers extendingNW from the “bowl,” and resemblingsomewhat the figure of a horse. A

small “prize” you’ll want to look forwith your scope is the “SnakeNebula,” B-72, a small (20 arc min-utes top to bottom) S-shaped darkobject, just NW off the Pipe’s bowl.Find 4th mag. 44 Oph 1˚ 20 arcminutes NE of q, then turn 90˚ NWand slide 40 arc minutes to find the“Snake.”

Now we move from the Pipe’s bowlabout 9˚ SE back into Sagittarius andto g Sgr, 3.5 mag. Alnasi at the tip ofthe Archer’s arrow. From here we turnjust W of N from g passing over thevariable star W Sgr, and traveling alittle over 21/2˚ to arrive at a visualfeast, truly a “showpiece,” much neg-lected as a deep sky treasure amongthe many others nearby. This is NGC-6520, a spectacular open cluster ofdensely packed young blue-white starson top of the great Sagittarius StarCloud, with its “companion” immedi-

ately to the NW B-86, the famous “InkSpot.” Its roughly triangular shapecovers about 6 arc minutes and com-pletely hides in sharp contrast thecloud of stars behind. Added to thisscene is a beautiful bright orange 7thmag. star at the NW edge of the darkblot. All together, the “Ink Spot” B-86,along with its close neighbor, is anobject you should put on your “mustsee” list B86 is a dark nebula inSagittarius that is called the “InkSpot”. Just to the left of it in this imageis open cluster NGC 6520.

There are dozens of other dark nebulaepopulating the summer sky – we’vebarely scratched the surface – most ofthem catalogued by Barnard. So, onthe next dark transparent night, plan toenjoy some of your observing time“Seeing Dark in the Dark.”

B 72 - The Snake

B72 Region imaged by Chris Cook


Star PeopleReal People in Astronomy

Article by Robert Reeves

All Images by Sara Wager

Name: Mike Peoples

Residence: Pennsylvania

Occupation: Sport Optics and Telescope

Retailer

Astronomer since: 1965

Websites: www.pocmtobs.com

Amateur researcher and telescope retailer Mike Peoples is widely known as a friend of the amateur

astronomer. Now Michael in embarking on a new adventure with his own telescope company. This is

Mike's story...

Astronomy has been part of mylife for 51 of my 58 years.Yes, I started at the age of 7

viewing from my fire escape andbackyard in Brooklyn, New York. Inthe mid 1960’s I could see M-13 andM-31 with the naked eye. That cameto an end in the early 1970’s whenNew York City installed bright mer-cury vapor lights.

I am self taught in astronomy. I readall the Sky and Telescope, Deep Sky,and Astronomy magazines, and all theastronomy books in the school andpublic libraries. I love comets, super-novas, deep sky objects and solarimaging.

When I moved from Brooklyn to thePocono Mountains in the mid-1980's Ibegan doing serious astrophotogra-phy. I was nudged into this field afterreading the books about CCD’s andastrophotography by Jack Newton,Robert Reeves and Don Parker.

In my years of astronomy I haveowned about 50 telescopes. I startedoff with a Tasco 4.5-inch reflector andquickly moved to a Celestron C-8.Instruments have ranged from theMeade 16-inch Deep Sky Series to a3.5-inch Questar. The scopes I usetoday are the Celestron C-11, C-8 andC-5, the Tele Vue NP-101 and TV-

60IS, and a Meade LX-200 10-inch,ETX 125 and the 12-inch ACF LX850EQ system that is now in my observa-tory. My favorites scopes for imagingare the Tele Vue NP 101, the ExploreScientific ED 127, and the Meade 12-inch ACF. For visual observing I usemy 15-inch Obsession Dob.

I do have many hobbies besidesastronomy; they include, shooting,hunting, birding and camping. I amalso interested in model trains, whichI haven’t been doing in years. If Iwere not so involved with astronomy,I think I would be more involved withcompetitive shooting in the 1000 yardlong range class.

What excites me the most aboutastronomy are things that are not stat-ic like supernovas, comets, and minorplanets. I do enjoy astrophotographyas well. I try to image or view everyclear night, but the weather in thenortheast the past few years has beenterrible.

Before I built my observatory, thePennsylvania winters could be rough.Once I was imaging when it was -4degrees. A after about four hours Idecided to go inside and get some hotchocolate and warm up. I discoveredthat I could not get up to walk, myknees were stuck in the sitting posi-

tion! I had to crawl in the snow backto the house. I opened the door andthe wife was looking at me and justshook her head and said, “You wantedto image, don’t cry to me”. I sat bythe coal stove and experienced thatpins and needles effect you get whenwarming from extreme cold. Asunpleasant as the cold was, it wasn’tas scary as the time I was observing inthe back yard and noticed a 600-pound Black Bear sitting not far fromme and eating blackberries from abush.

Now if the weather is bad I go onlineor plan my next observation session.Besides the weather, my biggest prob-lem is trying to get enough sleep!!Setting up and breaking down everyday was a real chore, but I partiallysolved that by building my own back-yard observatory.

My best images so far have been ofM-31, M45 and NGC-6992. As goodas I think these photos are, I knowthey are tempered by having made allthe mistakes that an astrophotograph-er can do, such as taking a three hourexposure and forgetting to uncoverthe guide scope!!

I think one of the best recent develop-ments in amateur astronomy has beenthe widespread popularity of DSLRs


for astrophotography, particularly nowbecause of their greater sensitivity andlower noise. I would like to see lowerpricing, so the average person can getinvolved, and also DSLR’s that arecooled for even greater noise reduc-tion. The planetary imaging camerasand processing software are also ter-rific now! Just look at the images myfriends Christopher Go and EfrainMorales have taken of Jupiter, Saturn,and Mars and Robert Reeves of theMoon.

If I have any advice for a beginner inastrophotography, it would simply bethat if you take up astro-imaging, stickwith it!!! And remember that it is nota competition, you only need to pleaseyourself!!

My biggest surprise in astronomy isthat, as an amateur astronomer. I, wasable to be the co-discoverer of 24supernovae as a team member of thePuckett Observatory SupernovaSearch (POSS). Over the years thisprocess involved looking at almost amillion separate galaxy images. Mostof these I looked at, about 300 at atime, while commuting to work on thebus to New York. The highlights ofthis activity include finding the TypeIa supernova 2005mz in NGC 1275,which is one for my favorite galaxies!I am also pleased to have found twosupernovae at the same time in thegalaxy UGC 4132, the Type IISN2005en and the Type Ia 2005eo,

Mike got “nudged” intoastrophotography after movingfrom Brooklyn to the PoconoMountains and reading booksabout the subject.

The image of M31 (right) wastaken from his home observato-ry (PMO - Pocono MountainObservatory) pictured belowwith his Meade 12-inch ACFpeeking out from the slide offroof.


which could be a record for the onlyones found consecutively in the samegalaxy. I am really pleased that thePOSS team data on supernovae hasbeen used in many professionalresearch papers with articles aboutType Ia supernovae, a new class ofsupernova and also on the expansionof the universe. I am also proud ofwork that measured the period of acataclysmic variable star. That proj-ect took about four years of observa-tions.

My “day job” is retail sport opticsbuyer. I have been in the retail end oftelescopes for quite a while. Once acustomer came in with a professionalastronomer to check over the tele-scope he just purchased. About 15minutes after they left, I heard a loudcommotion in the parking lot. I wentout to find the professionalastronomer had been trying to colli-mate an SCT and dropped the second-ary mirror onto the primary. The cus-tomer looked at me and I said“Observatories don’t use astronomersto work on their scopes; they use tele-scope technicians”.

Today I belong to three differentastronomy clubs, the GreaterHazleton Area Astronomical Society

(GHAAS), The LackawannaAstronomy Society (LAS), and theRockland Astronomy Club (RAC). I

consider Al Nagler to be my guideand mentor in this hobby. Most of the

time I observe alone, but once in awhile, mostly for major events, mywife Louise will join me.

With help from Bob Moore and myson-in-law Alex Diaz, I finally built

One of Mike’s biggest surprises inastronomy has been his participa-tion, as an amateur astronomer, inthe co-discovery of 24 supernovaeas a team member of the PuckettObseravtory Supernova

Over the years that involved look-ing at almost a million separategalaxy images. The highlights ofthis activity include finding twosupernovae at the same time in thegalaxy UGC 4132, the Type IISN2005en and the Type Ia 2005eo,which could be a record for the onlyones found consecutively in thesame galaxy.

Below: Mike also enjoys observingwith a variety of instruments,including his 15” Dobsonian


my own observatory in October of2015. I call it the Pocono MountainObservatory (PMO). It is a six-by-sixfoot roll off roof facility about 75 feetfrom my back door. I have made sev-eral little improvements to help me,such as LED lights for setting circles,observing hoods, and covers for lap-tops. Even with all my telescopes, Istill dream of better equipment like aBisque ME or an AP 1200 mount witha 12-inch or larger Planewave tele-scope.

Overall, I believe astronomy hasimproved my life, first in businessand in meeting many good peoplefrom around the world. I have over3000 people on my Facebook pagemostly dealing with astronomy. I amalso the co-founder and co-chairmanof the Northeast Astro ImagingConference (NEAIC). We just cele-brated our 11th year for that event. It

has also been fun being on the staff atevents like the World Science Festivaland the Star Party at the NationalMall. I also love speaking aboutastronomy at events, clubs, andschools.

What keeps me interested is the won-der and expanse of the Universe, andthe awe one feels looking up in a darksky. I also get to travel a lot withastronomy. I went to Alaska with theUniversity of North Texas as a teammember for the 2012 Venus transit togather images on the tear drop effect.Since the 1990’s I have also been allover the country at star parties as avendor of astronomy products for var-ious companies.

Sadly, I see a future decline in ama-teur astronomy due to the fact that it isnot taught in most public schools any-more. Also adverse affects of, climate

change, and more light pollution. Formy part, in the future I will do my bestto keep this from happening byattending star parties, solar events andparticipating in public outreach.

I am also happy to announce that afteryears in the telescope retail business,I am opening my own web based tel-escope business called PoconoTelescopes. I invite all my friendsand potential telescope buyers tocheck it out at www.poconotele-scopes.com or contact me at [email protected].


Milky Way ChroniclesAdventures imaging our host galaxy arching over stunning earthscapes

David Lane

Dead Horse Point-blank. The normal view of DeadHorse Point, and it's a beauty, lies way above thisview. There's a reason for that too. The road down

to this point is dangerous, mind bogglingly steep and guar-anteed to give you white knuckles or worse. This road is notfor the faint of heart, mind or legs. Attempting this roadwithout proper equipment (I would recommend 4 wheeldrive as a minimum) could end up being deadly. The roadis certainly breathtaking but it still remains a heart pound-ing experience. Words can’t adequately describe the steep-ness and pictures frankly do no justice to the fear factor atall.

Headed down to the bottom the road certainly starts outwell, wide and in good condition. Then the wide expanse tothe left begins to narrow quickly becoming a rock shelfroad hugging the side of the cliff face thousands of feet inthe air. To make matters worse, the drop is not the least bitgradual. If you glance to the left, the sheerness of the dropwill buckle your knees. The road here on the cliff face is sonarrow I can't imagine having to pass another car. Today

I'm in luck and don't have to.

After looping around the cliff face a few times I came to thestart of the switchbacks. Here is where the real adventurebegins. Hairpin turns with barely enough room to turnbefore going in the opposite direction. Scant inches sepa-rate my tires from an unimaginable fate. You simply can'tthink about it. Seriously. And look? No way.

The good news is that the road leads to several beautifulpoints; several points that make it worth the white knucklesand puckered extremities. Dead Horse Point, MusselmanArch and Thelma and Louise's jump point. The famousconvertible jump spot in the movie actually wasn't in theGrand Canyon but about 3-4 miles from this location. Ihave to admit I loved this view of Dead Horse Point thesecond I saw it. My only wish was the Milky Way moreshifted right but it's still a decent view in my mind. Maybeyou will agree.

One trouble with Milky Way images in April is how late the


Milky Way rises high enough to climb out of the muck onthe horizon. At 2:30 in the morning I awakened in my trustyGMC Jimmy 4x4. I had parked at Musselman Arch to awaitthe rise of the Milky Way. Staggering out of the car after anabrupt awakening to walk to the edge of a cliff may not bethe greatest idea in the world. Carrying a pile of equipmentwith me that will be placed two feet from the cliff edgemight be an even worse idea. It is however what is requiredif you want to get the very best shot.

After completing the shooting at Musselman Arch I headedfor Dead Horse Point. This is an adventure in its own right.More sheer cliff faces with drops of hundreds of feet. Thistime at night. In total darkness.

The Dead Horse Point image started about 4:00 in the morn-ing and finished just short of astronomical dark. I managedto beat the end of astronomical dark by a scant 15 minutes.All the driving, waiting, and potential danger to completetwo images.

At least it was a beautiful night at Dead Horse Point; tem-peratures had hovered in the mid 50's with a slight breeze

drifting in from the west. As I stood on the ledge waiting forthe image to finish the waters below me swirled and gur-gled. I felt as if Mother Nature appreciated the company ofthe solitary observer. It was truly a magical night to be outobserving the skies.

The image: is 42 panels stitched in a 7x6 format, using aCanon 6D, 50mm lens at 1.8, ISO 6400, assembled and cal-ibrated in Pixinsight and Photoshop.

Technical Tip: The Milky Way Chronicles tip for this issue.Lenses: The lens you use is key to the image you will devel-op. The lens is what makes the image, the camera justrecords it. I never use a lens with less than an f/2.8 aperture.Seriously, unless you are just practicing, just don't try to getan image at any f-stop above this. Most of the lenses I useare in the f/1.8-2.0 range and the difference is stark. Doyourself a favor and get yourself a low f-ratio lens and makeyour job vastly more easy. You can get a Rokinon 24mmf/1.4 for as little as $500ish, its a great place to start and alens that can produce excellent results. If you get a lower f-ratio lens its a good idea to step it down from say f/1.4 tof/1.8 to help with vignetting and star shape in the corners ofthe frame.

The amount of sky you can cover with a single image isdirectly related to the aperture of the lens in millimeters.The smaller the millimeter the lens, the more area of the skythe lens will cover. An 8mm lens will probably cover theentire sky while a 85mm lens will cover a small fraction ofit. At first glance it would seem that covering the whole skyin a single shot would the proper way to image the night sky. There is a problem with that idea. Detail is lost and theamount of time you can expose the whole sky is reduced. Bydoing a more detailed panorama you can gather 20-30 min-utes of light for a single composition. This makes a vast dif-ference in the final image.

Be sure to check last issue for tips on how to focus a wideangle DSLR.

If anyone has something that they have just been burning toknow how to do, write ([email protected])and let us know. If we pick your question it will become atip of the issue in a future article. Until then remember tokeep looking up, and that you too can take great images ofthe night sky. Clear skies to all of you.

David’s preferred nightscape panorama imagingsetup includes the iOptron iPano, Canon 6D and afast lens (f/2.8 or faster).You can check out his reviewof the iPano on page 22.


The object of this article is to propose a method ofeliminating the stray light that comes through the eye-piece of a Newtonian telescope. As might be sus-

pected from the title, the method has something to do withthe unorthodox use of gloss black paint.

I have tested several eyepieces and found that light comingfrom 30 degrees or more off axis can not be seen. For manyeyepieces, the limit is less than 30 degrees. Therefore, a baf-fle opposite the eyepiece, subtending 30 degrees, will stopstray light from entering the eyepiece directly. If the tele-scope is enclosed by a tube or a shroud, then light can enteronly from above. Figure 1 shows this arrangement with alarge enough baffle, painted flat black, so that the only straylight that can reach the eyepiece field stop is that which isreflected from the baffle.

Suppose that stray light, with an intensity of M photons persquare inch per second, enters as indicated by the arrows.The coefficient of reflectivity of black paint is .03, so theintensity of the reflected light will be .03M at the surface ofthe baffle. Because flat black paint distributes the reflectedlight evenly in a hemisphere, each point on the baffle willsend some light toward the eyepiece. The intensity of straylight at the field stop, from each point, will be the ratio ofthe area of the field stop divided by the area of the hemi-sphere at the baffle-to-field-stop radius. The total stray lightat the eyepiece will be:

I(f) = (.03)M(sin A)(Pi*R^2)(Pi*r^2)/2PiB^2

Where I(f) is the intensity at the field stop with flat blackpaint, .03 is the coefficient of reflectivity, M is the initialintensity of the incoming stray light, A is the angle of theincoming light, Pi is 3.1416, R is the radius of the baffle, ris the radius of the eyepiece field stop, and B is the averagedistance from the baffle to the field stop.

The numbers in Figure 1 represent the telescope that I amcurrently in the process of building. It is a 10.5” f/6.5, andfor this set up, the intensity is:

I(f) = .0027M photons per second.

Figure 2 shows the same set up but with the baffle paintedgloss black. Gloss black has the same coefficient of reflec-tivity as flat black, but it acts like a very inefficient mirror;the angle of incidence equals the angle of reflection. Figure2 shows that only a small portion of the baffle is in the cor-rect position to reflect light into the eyepiece field stop, butit delivers the full intensity of the incoming stray light,decreased only by the coefficient of reflectivity.

I(g) = (.03)M(Pi*r^2)

Where I(g) is the intensity at the field stop for gloss blackpaint, .03 is the coefficient of reflectivity, Pi is 3.1416, andr is the radius of the eyepiece field stop.

For the same telescope as above, the intensity for glossblack paint is:

I(g) = .0245M photons per second,

or almost 10 times worse than with flat black paint.However, that is the case only when angle A is fairly large.In the case where angle A is 57 degrees, for flat black paint,the intensity at the field stop is:

Stray Light Suppression and Gloss Black PaintLarry Shaper


I(f) = .0023M,which is a little lower than for 80 degrees shown in Figure 1,because the baffle is intercepting a smaller portion of theincoming stray light. Figure 3 shows the 57 degree casewhen the baffle is gloss black. At this angle, and all smallerangles, the baffle reflects all of the incoming light below theeyepiece, and the intensity at the field stop is:

I(g) = zero.

Now the only problem is to get rid of the light coming fromlarge angles to the optical axis of the telescope. This can bedone in either of two ways: 1.) make the optical tube longenough to block the light, or 2.) tilt the baffle to force all thelight to miss the eyepiece field stop. The first method isstraight-forward, but it increases the size of the telescope aswell as the mass, in a place where it is usually most unwel-come.

Figure 4 shows an example of the second method, with a fewmore of the usual details of Newtonian telescopes. The eye-piece is in a 2” focuser draw tube with a 2” travel, whichhelps to cut off some of the stray light. The telescope tubeextends all around the optical axis, high enough to containthe baffle, thereby doing some of the work by the firstmethod. Two stray light rays are shown. Ray 1 enters just abit above the perpendicular to the optical axis. It is reflect-ed by the tilted baffle to hit the bottom of the eyepiece fieldstop. Any rays coming in above Ray 1 will be reflected evenfarther down the tube. Ray 2 is just high enough to strikewhere the baffle becomes vertical, and it too, along withhigher rays, is reflected to go below the eyepiece. Now weare almost there. Light can still reflect off the eyepiece sideof the tube, reflect again off the baffle and then into the eye-piece. The intensity of this light will be doubly reduced by

two reflections; it will be (.03)*(.03)*M or .0009M. To stopall stray light, a back baffle should be added, as shown inFigure 4. Also, it should be mentioned that if any lightreflected off the baffles or the sides of the telescope tubefinds its way to the primary, it will, of necessity, be at far toogreat an angle to the optical axis to be to be focused towardthe secondary, let alone to the eyepiece field stop.

Although just about every optical devise, including tele-scopes, gets covered with the flattest black paint that can befound, I think that it is the wrong thing to do. I have a pieceof wood with one half painted flat black and the other halfpainted gloss black. The flat black half always looks gray.The gloss black half looks black, except at the angle at whichit reflects the Sun, or the Moon, or the neighbor’s outdoorlights. If the baffle is gloss black and tilted the right amount,it will always be black as viewed from the eyepiece.


In issue #90 of Amateur Astronomy I wrote about myfirst baby steps into ATM and showed you that you don’tneed fancy tools and equipment to start making or

tweaking your own astrogear. In this issue I will take ATMto the next level and will show you some of my so called“intermediate” ATM projects. In this stage you might haveto make some plans with sketches and calculations to getyou started, and for a better end result you might need bet-ter tools. Still you won’t have to be a carpenter or a mechan-ical engineer.

First I will show you how I built an equatorial platform formy 8” Dobson, and next I will show you my parallelogrammount for a pair of binoculars.

The equatorial platformWith all the light pollution in the Netherlands, most Dutchastronomers are into astrophotography. And yes, a long,long time ago, I wanted to try to make some fancy astro-pic-tures too…. Soon I realized that a Dobson is not suited at allfor taking pictures. I didn’t give up, and after surfing theinternet, I discovered that stunning pictures of the Moon andthe planets could be made with just a simple webcam and aDobson on an equatorial platform.

There were few options to buy an equatorial platform in2003. Yes, there were platforms for sale, but they would costyou an arm and a leg. If you wanted a cheap equatorial plat-form, you had to make one yourself.

My first ATM-project ‘the conversion of a 8” Newton on atripod to a Dobson telescope’ required no planning ordesigning. For my next project, the equatorial platform, Iwanted to do better and without knowing I advanced to theintermediate ATM stage.

Calculations and sketchesWhen you decide to build an equatorial platform yourself,the first things you want to know are:• how does an equatorial platform work and• what is the underlying principle of the platform.Luckily, I was able to find the Yahoo forum “eqplatforms”with its wealth of information. The forum provided an excelsheet in which you only have to fill in some parameters. Allthe angles and dimensions are automatically calculated foryou. With this excel sheet, I could easily understand theprinciple of the platform, and make my own design.

Adventures in ATM Intermediate ATM

By Andre Heijkoop


The main dimensions of the platform are:

The rotation angle (11.25°) represents the tracking time of theplatform:11.25° / 360° * 24h = 0.75h = 45 minutes

Below is the table with the dimensions in cm. In Grey the input parameters, in black the calculated output values:

Bill of Material • 18mm plywood• 40x90 mm meranti wood• 30x2 mm aluminum• In line skate wheels ø 72mm, hardness Durometer 82A and ABEC 3 bearings• Hurst stepper motor AS3004-001SP2702• Unipolar stepper motor driver CK1404 from Carl's Electronics Inc.• Ø22mm Nylon stepper motor drive wheel


I made some rough sketches on a scale 1:1 to get a feelingof the actual size of the equatorial platform. Below, one ofthe many detailed sketches I made of the platform:

The North bearing supportsThe wooden blocks, that support the in line skate wheels,were not easy to make with all those different angels.

Constructing the North bearing sectorSometimes you have to make your tools suitable for gettingthe job done. In the picture below you can see, that it justtakes a simple extension to your router to make a nice radiuson the North bearing sector. I made 2 of these North bearingsectors and glued them together to get a sector of 36mmthickness.

Assembly of the equatorial platformOn the next page, you can see the equatorial platform takingshape.The direct drive; A ø22mm nylon wheel is attached to theHurst AS3004 stepper motor axis. The nylon wheel with theHurst stepper-motor is spring loaded to an in line skatewheel at the north sector. The in line skate wheel drives theplatform. With this set up, the stepper motor makes anapproximately 19 steps per second. The 19 steps per secondis sufficient for a smooth tracking without visible vibrations,even on high magnifications.


With the spring, it is simple to get a quick release of the drivewheel during Polar alignment, or when a fast rewind of theplatform is needed.

I am a mechanical engineer with, at that time, no experiencein electronics. Luckily, a friended astronomer could help mewith soldering the circuit board for the stepper motor.

The equatorial platform completed(above bottom right) When the last bits and pieces are done,the platform is ready for its test drive. And what a joy ifeverything is working as planned.

Webcam resultsOne of the purposes of the platform was taking pictures ofthe Moon and the planets. Here is a webcam result madewith the 8” Dobson.I did get somewhat better results with the 14” Dobson, but inthe end, I found out that webcamming is just not my cup oftea:

Handle bars and wheelsAfter a year of playing with the 8”Dobson on my homemadeplatform, I acquired a severe case of aperture fever.Fortunately, I made the platform big enough, so it could sup-port even a big 14” Dobson. The whole set-up made mewonder about the portability, and I soon realized handle barsand wheels were needed.

I leave the handle bars almost always attached to the equato-rial platform; they are on the north side of the platform, andin the field hardly ever in the way.

The wheels are attached in no time. I just lift the south sideof the platform and roll them underneath. I let the aluminumU-profile underneath the platform rest on the threaded rodbetween the wheels, and gravity does the rest.Image page 54


The parallelogram binoculars mountAnother small, but really fun ATM project was the parallel-ogram mount I made for my binoculars.

I didn’t make any calculations, sketches or drawings, I justlooked how others made their mount and just copied bitsand pieces of their designs.

On top a 15x70 binoculars, and on the L-arm a 15x85 binoc-ulars:

Bill of material• Giro mini for the azimuth movement.• Nuts and bolts• Some wood• Some stainless steel • Weight dumbbells• A nylon shaft• An old tripod

In this issue, I showed you how I made an equatorial plat-form and a mount for my binoculars. With a little time,patience, and perseverance, you can certainly make themyourself, learn from your mistakes. It is not rocket science !

In the next issue, we move on to the “advanced” ATM level.I will show you an ATM project, which took me about threeyears to finish.


Harry Roberts

Around dec. 70 degrees south liesa fascinating observing chal-lenge (thanks Eugene!): the

‘Meathook’ galaxy NGC2442. In fact,it has two numbers, 2442 and 2443 –since Herschel J saw it as two objects:we will use 2442 here.

There is a lot of dust obscuring much ofthe sky south of the galactic equator: as‘binos’ show – and our ‘target’ is amuch ‘reddened’ object: see JoeCauchi’s superb ‘pic’in “Universe”Vol. 1605. Volans, Lacaille’s ‘FlyingFish’ constellation, is a faint but elegantone just west of dazzling“Miaplacidus”, Beta Carinae.

Visually N2442 is an easy object tomiss when sweeping – as two fruitlessnights proved. However, the chartsshowed a wide pair of mag. 7 blue starsnearby– and they aided in finding thetarget site. Oddly, small galaxy N2434was the first ‘deep’ object spotted and itis much brighter than any part of the‘Meathook’- clearly the ‘hook’ was tobe a tough ‘get’. The next ‘signpost’was a neat triangle of ~12mg stars, oneis orange, just E of the galaxy: N2442was soon centered in the field. Whatwas visible?

At first a soft round haze was ‘held’,then averted vision showed a large faint‘thing’ occupied much of the field.Strangely, it turned out that the bestview was had with an old 9mm ortho-scopic e.p. that hadn’t been used indecades: it gave a small f.o.v and thebest contrast of any others in my set. Along central bar with faint hooks ateach end was seen: for brief moments adistinct hook was detected at the N end– perhaps due to unresolved 14mg starsthere. Tiny galaxy P21457 was seenclearly just E of N2442, it must be atleast 50% brighter than any part of the‘Meathook’. Later, with a friend’s 12”Dob and 9mm Delos the tiny ‘stellar’nucleus was ‘got’ in steady moments,and later on, again with the 9mm ortho’in the old ten inch. The 12 inch gave

the better view and the ‘MeathookGalaxy’ is one for bigger ‘scopes – itmust be a great sight in an 18” or larg-er.

On eye-piece design, I noted that cometobserver Chris Wyatt extolled simplerdesigns in his NACAA 2016 presenta-tion - and I was impressed by the bettercontrast in the 9mm ortho’s field: theyhave only four elements. The narrowerfield helps too by excluding ‘junk’from brightening the field of the targetobject: of course they are no use insweeping wide fields. But, ‘horses forcourses’, if you can find any ‘orthos’

you may like the better contrast theyoffer.

As mentioned, the ‘Meathook’ galaxyis deeply reddened – and the eye hastrouble seeing red deep-sky objects:our peak response is in the blue-greenspectral region. The arms of this bigbarred spiral must be mostly blue stars– that is, it would be a great sight wereit not for that foreground dust making ita challenging but worthwhile object.

N2442: A Hook amid Flying Fish


When I attend star parties andgive presentations on pro-cessing images with

PixInsight, people often ask me aboutmy workflow. This is a tough questionbecause each image is different, maybetaken in differing sky conditions, like adark site or at home (which isn’t dark).Even the type of object and field ofview requires slightly different tech-niques to get the most out of an image.However, there are certain steps, whichare common to all types of data. In thisarticle I will run through these steps ofimage calibration, evaluation, registra-tion and stacking order to show you thebasics of what to do when processingyour images with PixInsight.

This tutorial is based on the latest ver-sion of PixInsight which is1.08.04.1195 Ripley. PixInsight has aplethora of tools and I can’t cover themajority of them in this article so Ihope to provide future articles coveringsome of the tools and how I used them.In the meantime, tutorials and tech-niques can be found on the PixInsightwebsite and forum and there is also anexcellent commercial DVD and onlinetutorial of the software produced by

Warren Keller, which can be foundhere: www.ip4ap.com/

I first began using PixInsight in 2004,when it was first announced. Becausemost of my imaging was done at homeand my sky had significant light domesI was desperate for software thatallowed me to deal with light pollution.PixInsight was the first software thathad tools to effectively let me deal withlight gradients which is of the utmostimportance when producing colorimages.

I’ll tell you up front that astronomicalimage processing can be a dauntingtask, especially if you collect your datain less than dark skies. It takes a sig-nificant amount of time to learn andwhichever software you use, the learn-ing curve is steep so take your time,learn and have fun with it

HistoryPixInsight was developed by JuanConjero (Pliedes Astrophoto) alongwith many collaborators in the imageacquisition and processing field. Itstarted in 2004 as a freeware app called

PixInsight LE. From the beginning,PixInsight was designed as an image-processing platform for astronomy. In2008, PixInsight became a commercialplatform and continues to evolve asnew processes and scripts are added.PixInsight works with all the majoroperating systems so whether you havea Mac, Windows PC, or Linux comput-er, PixInsight may be the right choicefor you to process your astro images.

My workflow is designed around sev-eral assumptions. The first assumptionis that along with your images, you col-lected calibration data, which includesdark frames, bias frames and flat fieldimages. While you can process imageswithout these calibration images, yourresults will greatly depend upon youroptical system and camera. So lets getstarted.

CALIBRATION: The first thing you want to do afteryou’ve acquired all your data is openPixInsight and select “script”, “batchpreprocessing” and “batch preprocess-ing”. This will open a window, whichlooks like the screen shot above.

My PixInsight Workflow Part 1Calibration, Image Evaluation, Registration and Stacking

by Jon Talbot


This is the tool, which will be used tocalibrate your images. Along the topare tabs. Each tab is a separate windowin which you will put your calibrationdata and main image data (Lights).Clicking on the Bias tab and then onthe bottom “Add Bias” will bring up adialog box, which will let you navigateto your bias images and select themand add them to the window. Don’tworry if you binned your images, asthe app will sort them accordingly.The tabs labeled “Darks”, “Flats”, and“Lights” work the same way. You seea check box selected near the middlecalled “calibrate only”. When checkedthis tool will only calibrate yourimages. You also have the option toregister and stack your images withinthis tool if you leave this unchecked. Idon’t do that since I want to look at theimages after I calibrate them and thereare separate apps for this within theprogram with more options. Over onthe side under Global Options, thereare check boxes which allow you toselect other options. I leave Optimizedark frames, Export Calibration filesand Up-bottom FITS selected.

One word about using images fromDSLR cameras. DSLR cameras pro-duce color images from a Bayer colormatrix containing red, green and bluepixels. In order to calibrate them cor-rectly, you need to make sure “CFAimages” is checked. CFA stands forColor Filter Array. When this is select-ed, your images will be calibrated cor-rectly and you have the option to auto-matically DeBayer them and the win-dow in the center of the app calledDeBayer will become active. I recom-mend you do this with DSLR cameras.

You also have the ability to write theoutput files in several formats. Thedefault is .xisf, however if you prefer.fits you can just type it in here. Seethe online resources for other support-ed file formats.

The bottom right corner of the appallows you to select where and whatdirectory to put your calibrated imagesinto. Finally along the bottom is a but-ton called Diagnostics. Clicking thiswill check your files for any errors.When ready click “Run” and the appwill produce master Bias, Darks, andFlat frames which will be used to cali-

brate your images. The resulting mas-ters will be put into the directory youselected and your calibrated imageswill be put in that directory under asubdirectory called lights.

Now that we have our calibrated data,the next thing I always do is look at theresulting images using the app called“blink”. Blink allows you to load yourimages and blink through them and seehow they look. Sometimes faintclouds could have been movingthrough the image field and maybe youdidn’t notice when you took theimages. Blink allows you to seechanges in the images as you blinkthrough them and discard the ones youdon’t want.

BLINK:Blink can be found on the processexplorer tab as a default under“favorites” (screen shot above).

You open images by selecting the fold-er tab at the bottom. This will load theimages and you will be left with a win-dow open showing the first image.


The next step is to click the histogrambutton next to the image preview win-dow. This will auto stretch the imagesto the same histogram. Optionally youcan click the bottom button, whichlooks like a bar graph to get image sta-tistics. I manually use the right arrowto click through each image looking forclouds obscuring the view or bad track-ing as seen in elongated stars. You canzoom in on the image using + button onthe top of the PixInsight menu bar.Finally I uncheck each image, which Ithrow out and blink through them againto make sure these are the ones I want.I highlight each good one and click onthe disk icon on the bottom to savethese “good” images to a folder. Thesewill be the ones I register. Its always agood idea to write down or rememberwhich image is the best one which isthe one all the rest will be registered toand compared against. I use statisticsto do this. Usually the image with thehighest standard deviation is the one touse. More info on what these statisticsmean can be found in the onlinePixInsight help our by clicking the“resources” tab at the top of the mainscreen.

Once I have selected all my goodimages its time to register them so thatall the stars overlay one another. SinceI dither my images when acquiringthem, each image is shifted slightlycompared to others. By dithering youare able to take advantage of applyingpowerful rejection algorithms whenstacking your images which will auto-matically reject things like hot pixels,satellite trails, etc.

IMAGE REGISTRATION: The image registration tool can befound under the process explorer tab onthe side or “process” menu at the top ofthe screen. Navigate to “process”,“image registration”, “star alignment”.

The star alignment window looks likethe one above. The first thing you do isselect your best image which will bethe reference to which all others arealigned to. This is usually my bestluminance image using a ccd camera orbest image using a DSLR. Then youclick on the “add files” button on the

side and add all the rest of your images.It doesn’t matter whether they are thesame size, rotated, or binned smallerthan your reference image. In the win-dow above I have 41 images loaded.My luminance was taken at full res and1x1 binning and my color filteredimages at 2x2 binning. Some are onone side of the meridian and some onthe other so they are rotated. Leave theregistration model as default and theworking mode should beRegister/Match images. Under OutputImages I select the directory I want theregistered images to go to and I leavethe rest as default. Star detection andStar Matching are also left as default.Interpolation is set to auto and I changethe clamping threshold to 0.10. To get

a better idea of what this entire dialogbox does, click on the middle icon onthe lower right of the dialog windowwhich will bring up documentationabout the star alignment window.Finally click on the round blue buttonon the lower left which will apply thisinstance globally to the images youselected. PixInsight will register eachimage to the reference image and youwill see the process in real time on theprocess console window which willopen. Once done, you will have allyour registered images in the folderyou selected. They will be rotated andresized to match your reference image.


IMAGE INTEGRATION: Image integration is the process of dig-itally combining all your registeredimages to make a master image whichhas a high signal to noise ratio. To dothis, select the image integration toolfrom the Process Explorer tab orProcess tab at the top. Select“ImageIntegration”. This will bring upa window looking like this.

Select the add files button and loadyour registered images. In this case Iloaded by registered blue filteredimages. Next click on the image inte-gration tab.

The image integration tab within thedialog looks like this. I usually leaveeverything as default. More info aboutwhat each of these selections do can befound by clicking the browse docu-mentation tab on the lower right of theImage Integration window.

The next window you can expand isthe Pixel Rejection (1) window(below), which is by far the mostimportant. Here is where you selectthe type rejection algorithm you willuse to combine your images.Depending upon the number of imageyou have to combine will determinethe rejection algorithm you use. Myrule of thumb is: If I have more than 5and less than 10 images I use SigmaClipping. 10 or more images I selectWinsorized Sigma clipping. If I shotimages at home under light pollution,and have 10 or more images, I alwaysselect Linear Fit Clipping. Percentileclipping is used if I have less than 5images. The minimum is 3.

In the case above I had 7 images andselected Sigma Clipping. I leave allthe rest of the tabs at the default value.Pixel rejection tabs 2 and 3 allow oneto change the rejection ranges andallow one to use more advanced meth-ods to reject data. Read about them ifyour interested, otherwise leave every-thing default. Select the round bluebutton and PixInsight will use power-ful rejection and noise evaluation tech-niques to come you data into a masterimage. If you used a CCD camera andseparate filters, do this for the remain-ing sets of images to produce your

master sets using each filter.

Once you’ve gone through these stepswith your Luminance and filtered orDSLR images you will need to processthem to bring out the best they offer.That will be in the next article, as itdeserves its own stage. Topics willinclude getting rid of light gradients,color combining and stretching yourdata and making your data into a pret-ty picture you will be proud of to shareon the web or with friends. In themeantime you can check out theresources tab at the top of thePixInsight window to find tutorials andlinks to the PixInsight forum and youtube video page.

Happy Imaging.

Jon Talbot



Mercury transits the Sun 13times every century. Most ofthe globe was able to witness

a good portion, if not all of this 7.5hour event. The last transit occurredten years ago and the next one willoccur on November 11, 2019.

Initially I had intended to simply view

this event from home. About 10 daysprior, I received a call from an educa-tor that I work with frequently whorequested a solar observing session forher 4th grade class and asked about adate. A light bulb came on and I toldher that we had a special opportunitycoming up to not only view the sun,but a special event as well and asked if

Monday May 09 would work for herschedule. She immediately booked thedate. The next day she contacted meagain and asked if some of the otherclasses could also view the transit. Iresponded that I had several platformsto view the sun and could set up threetelescopes for viewing (2 in Ha and 1in white light). The next day she calledback again and said that all the scienceteachers were excited and could Iaccommodate 24 classes with a total ofabout 800 students. Never one to backoff from an opportunity to get youngfolks excited about science and astron-omy, I replied “sure”.

It did not take long for the logistics tosettle in and I began to make somecalls and send out SOS emails for“HELP”. We have a terrific group oflocal amateur astronomers, but not allcould take a day off of work.Nonetheless, I got commitments fromTammy and Craig Temple who offeredto help and also bring another 60mmHa scope, JD Powell helped run one ofmy scopes. Chuck Schlemm not onlybrought another white light scope, butset up a mobile “astronomy sciencefair” complete with solar system scalemodels and jugs filled to different lev-els with sand to dramatize the differ-ence in weight based on the gravita-tional pull for each planet. LonniePuterbaugh offered his services withsolar scopes and his complete“astrovan” setup, which not onlyincluded tons of educational video and

Mercury Transit May 9 2016

Imaged by Barry Riuusing his 152mm Lunt

Lonnie Puterbaugh giving a presentation with his incredible “astro van” equipped with large screen TVs


two large screen displays, but microphones and a 200 ampsound system to pump out vibes to keep the kids energy lev-els up. As a bonus, he also brought a 16 lb. meteorite so thatthe students could actually “heft” are real “space rock”.

Now that I had a complete crew and ample scopes, I need-ed to get some additional hand out materials. I had 850brochures printed with information about the Sun, Mercuryand transit event. I loaded up boxes with 850 copies ofAmateur Astronomy magazine, but really wanted someintroduction to Astronomy collateral as well. I contactedDave Eicher, editor of Astronomy magazine, .who gracious-ly had a box of “Welcome to Astronomy” and “ViewingMeteor Showers” expedited to us due to the short timeframe. I wanted to give out solar glasses to all the kids, buthad only about 100 left and we have been running way overour allotted budget this year due to increased outreachevents. I contacted Stephen Ramsden of the Charlie BatesSolar Astronomy Project (CBSAP) to see if he could sup-plement some, or sell me some bulk. Stephen, who is about

as passionate as anyone I know when it comes to outreachto schools went way above the call and generously sent abox of solar glasses so that all the students could have a pair,then to boot, he expedited the shipment. The generosity andwillingness to sacrifice by people involved in this hobbynever ceases to encourage, amaze and humble me.

The weather was not overly cooperative, but we did haveenough breaks in the clouds to give the majority of studentsviews of our nearest star and the “tiny” planet Mercury tran-siting the surface. The vast wealth of knowledge and addi-tional displays more than filled the voids when the Sun didhide behind clouds and the 800+ students had a wonderfuland educational time attending this impromptu astronomyscience fair assembled behind their school. I have posted avideo slideshow and timelapse of the event on my Vimeosite: https://vimeo.com/166763609

Charlie Warren

Above and counterclockwise: I give some openingremarks and answered questions. Tammy Templegives some teachers a look in Ha. Teachers and stu-dents enjoy solar glasses donated by Charlie BatesSolar Astronomy Project. Chuck Schlemm gives hissolar system presentation. JD, Tammy and Craig han-dling some of the telescopes on one side of the field.


AR12529 & 12524: A Tale of Two SunspotsHarry Roberts

The magnetic things calledsunspots do not arise randomlyon the Sun: in fact, they often

evolve at localized sites called activity‘nests’. The nests are not visible inoptical bands but can be seen in full-disc solar magnetographs (Fig6). Inwhite light, their presence may beinferred when several spots emerge atsimilar locations over successiveCarrington Rotations (CR). Neststhemselves do not last very long, but‘evaporate’ after maybe five or so rota-tions. Let’s consider two recent groupsthat may be members of a nest.

AR12529. (CR2175)This impres-sive spot group rounded the easternlimb about Apr 8, unseen due to clouduntil the 10th (Fig1), when a hugeround (p) spot, area~700units, waslogged with small spot clusters follow-ing (f) and threaded with active regionfilaments (ARF). The umbra of the (p)spot showed the beginnings of twolight-bridges (LB) as did H-alpha -with bright emission obscuring theumbra in places: one of Zirin’s keyflare predictors (“Astrophysics of theSun” P404). The centre of the big (p)was at +10,345 (heliocentric). The logsshowed this was a new group with nospots at the site in earlier rotations.

The group was generally assignedHale Beta classification with a simpleseparation of violet polarity, reaching2700G in (p) spot (with the 2006 pub-lished correction this is =3000G:among the strongest fields yet loggedin SC24) with red (f) spots. By Apr 15the many small (f) attendants had allbut gone (Fig2), yet some remained asshown. Mt Wilson saw two within thepenumbra (PU) of the (p) spot somehours before the Nowra log (two+marks in fig). Mixed polarity in thatone PU made the group briefly HaleDelta class: the most active spot class.

This (p) spot would prove verydurable: several complete light-bridgeswere logged with the solitary (p) spotundiminished in size when 18deg fromthe limb (not shown) on Apr. 18 and asa wafer-thin spot at the limb on the19th. Despite its ‘looks’ this grouphosted only a single M6.7 flare withsome C-class events despite its short-lived Delta status. Would it return?

AR12542. (CR2176) On May 4(UT) an interesting ‘binary’ pair ofattached spots was noted some 19degfrom the E limb at lat. +11deg. Transittimings and ‘Helio’ freeware sited thebinary at +11,357 and limb longitude

338; the old AR12529 (p) site laybetween the two: yet nothing was seenthere. Had the big spot gone? Given itslongevity during the earlier transit thiswas a bit surprising. Attention nowfocused on the new twin spots at 357:the pair was just 10degs west of the old(p) spot site; what did this indicate?

Proper motion? A review of the logsfor the 12529 (p) spot showed a steadywestward proper motion during April.Briefly: from 344 on Apr 10th to 348on the 19th i.e. about 4deg in 9dayswas recorded, ~0.5deg westwardmotion per day; not unusual for a (p)spot. From Apr. 19 to May 4 is 16 daysand implies 8deg of westward motion


during backside transit, and accordswith the spot ‘twins’ longitude of 357on May 4. That is, proper motion due tothe Hale-Nicholson force suggests theunusual twin spots logged on the 4thwas the return of the AR12529 (p) spotfrom the Apr rotation.

More motion and rotation? Logsfrom May 4 to 11 (Figs3 to 5) showcontinued westward motion of ~5degover the 7day period, consistent withthat noted earlier. As well the tworound (p) spots, just in contact, evolveinto a more common oval penumbrawith twin umbrae over that time – withevident rotation of the smaller spot

clockwise around the larger spot (Fig5,in blue) - to then merge fully – while anelliptical chain of smaller spots aroseeast of, i.e.(f), the merging twins: inter-esting spot evolution! Clearly thisregion of the Sun is hosting somedynamic activity; yet no strong flaresoccurred.

Activity ‘Nest’? The activitydescribed is sited around 10degN (+10)at heliocentric longitude 350 – but itsfull extent is much greater, as the mag-netograph shows(Fig6), with extensivesurface fields and pole-ward ‘streaks’or plumes of older surface magnetism,and may have an extended life. The site

should be monitored over followingrotations: in white light extensive facu-lae with or without spots may indicateon-going activity. In h-alpha brightplage and filaments are likely. Will newor related spots emerge there? Timewill tell.


Summer is the most active seasonfor star parties and as most ofyou know, I am a huge fan of

these events where amateurastronomers can get together and shareinformation about the hobby, see firsthand a large variety of equipment andshare the thrill of dark skies.

These are a few short journal excerptsand some of my favorite wide fieldimages from a few of my recent expe-riences. Don’t let the busy-ness of life

delay your plans to attend one or twothis year. I have never looked back andthought “I went to too many star par-ties this year”. Check out our StarCalendar on page 30&31 and makeyour plans today. You won’t regret it!

Above: The Milky Way arches over alarge number of telescopes and ama-teur astronomers enjoying the night onthe upper field at the Texas Star Party.TSP is certainly one of the premierdark sky events of the year. If you want

dark skies and a large number ofastronomers, equipment and speakers;Okie-Tex, Oregon and Nebraska arealso good candidates for those on thecontinental United States. It is hard tobeat the sense of awe that this and sim-ilar night landscapes inspire for thoseof us who are naturalists of the night.

Below: (Image and journal notes)Dawn Breaking over TSPThis is one of my favorite images fromthe 2015 Texas Star Party, because it

Star Parties Good Skies, Good Folks, Lots of Scopes

Charlie Warren

Milky Way at dawn TSP - C Warren


reminds me of everything that I loveabout a good star party. To set the stage;this was the last image that I took aftera phenomenal all-night vigil observingand imaging on the upper field. Dawnwas brightening the sky as our neareststar was cresting the eastern horizon,but our galaxy’s core was still plainlyvisible in the South, standing like a sen-tinel over the upper field crowded withnow shrouded telescopes. There wereonly four people left on the field,including myself and my field neighborand friend Dave Tosteson, who wasbusy covering his 32” telescope andsecuring it against potential daytimedust devils.

My body was bone weary from a longnight on the field, but I was strangelywired from the exhilarating memoriesof distant photons and exciting discov-eries still fresh in my mind. One suchwas my first ever view of a Voorwerpshared with me by Dave through his32” scope. Dave’s write up on thisobject is on page 16 of this issue.

As tired as I was, I could not sleep, so Imade the decision to have a heartybreakfast in town, then go on a birdingexpedition with my camera at the near-by Davis Mountains State Park. Sleepis over rated anyway. There will beplenty of time to catch up on sleep.Right now I want to drink in everymoment of distant light from remoteparts of the universe and soak in thewonder of this West Texas landscapeand its remarkable diversity of feath-ered native wildlife. I love Star Parties!

Next Page: TN Spring Star PartyThe Tennessee Spring Star Party is atwo day event sponsored by theCumberland Astronomical Society(CAS) and “Friends of the Parks”. Anumber of folks do, however, comeearlier and stay later. It is hosted on thebeautiful grounds of Fall Creek FallsState Park. If you viewed my video ofthe Perseid Meteor showers last year(https://vimeo.com/73210866) youhave an idea of how lovely this settingis with trails, waterfalls and even a sce-

nic golf course. To sum up this year; itwas good weather, good observing andimaging and great companionship.

The observing area is located near theInn and the Inn offers shuttle service tothe observing area until around 11:00.The area designated for observing hasan open, level gravel area with goodhorizons bordered by trees. The skiesare quite good with a very visibleMilky Way. Similar to many star par-ties, there is no power on the field, butthe hosts set up a nice warming tentwith various hot beverages and somesnacks.

Each year CAS rounds up a nice com-plement of speakers that always pro-vide a nice mix of observing, imagingand science related topics. The talks arepresented in a comfortable conferenceroom at the Inn and there are displayareas with a variety of exhibits. Thisyear’s included a very nice display ofmeteorites among others.

continued on page 66

TSP 2016: Jon Talbot took this amazing shot during the Texas Star party, but it is not from the Prude Ranchproperty, although close by. The Very Long Baseline Array (VLBA) is an interferometer consisting of 10identical antennas on transcontinental baselines up to 8000 km located from Mauna Kea, Hawaii to St Croix,Virgin Islands. The VLBA is controlled remotely from the Science Operations Center in Socorro, NewMexico. Each VLBA station consists of a 25 meter antenna and an adjacent control building.

Image details: Shot on a fixed tripod mount using a Hutech cooled/modified Canon 6D equipped with aRokinon 14mm f/2.8 lens. Jon took 5-30 second exposures combined into this mosaic, then processed theimages with PS camera raw and PixInsight 1.8


The cost is hard to beat. It is free. Theevent also serves as an outreach pro-gram to other visitors at the Inn, whoare invited to the presentations and theobserving area (with shuttle service). Imust say that I like this mix. I havealways had a passion for outreach andthis is one way to get some goodobserving/imaging time in along withsome outreach. The guests generallyslip off on one of the shuttles as it getslater and around 11:00, the seriousobserving and imaging begins.

The weather this year was hard to beatas well. After Winter, the mild low-six-ties temperatures and surprisingly lowhumidity were very welcome. Ibrought my dew heaters, but did noteven have to fire them up. Not some-thing that you can necessarily count onat this event though.

It is a small gathering (about 50 tele-scopes) compared to the large star par-ties, but the friendly, informal atmos-phere is just right. The mix is a bitheavier towards observers thanimagers compared to many star partiesI have visited of late. LonniePuterbaugh usually brings his roadshow, which includes a 14” Celestronequipped with hyperstar andMallincam video camera with hot linksto a twin 46” monitors loaded on hisoutreach “astrovan”. I will featureLonnie’s remarkable rig in a futureissue. Lonnie positions his van so thatthe twin monitors face out and they are

dimmed to where there is absolutelyno offending stray light that hits thefield. It made a nice reprieve to occa-sionally go by, sit on the bench with acup of hot coffee and enjoy a livegalactic view coupled with informa-tion on the mating monitor about thecurrent target. It is fun to see whatthese astro video cameras can do whencoupled with fast optics.

I would encourage those who are with-in reach, to join us at one of the futureevents. It is a great place to spendsome additional time with your spouseor family and enjoy some good fellow-ship with enthusiastic and friendlyamateur astronomers under good darkskies.

So, I hope you can plan to attend atleast one star party this season,whether a large week long event likeTSP or a smaller, 2-3 day event likeTNSSP, they are all much better thaneven a good day at work.

Dancing with the Stars: Not anuncommon sight at star partiesare attendees like these at theTNSSP pulling out their instru-ments for an informal jam ses-sion. Music and astronomy seemto go well together.

Milky Way over the observing field at TNSSP - C Warren


NGC 4216 by Curt Morton

After a six month hiatus from imaging Iwas finally able to return to Chiefland forsome much needed dark sky time! As isusually the case, I was immediately chal-lenged with equipment problems. It tooktwo nights to get a handle on what washappening.. Anyway, since my preciousimaging time was greatly curtailed, Iopted to concentrate on a single target forthe remainder of my stay. Sunday night(the 10th) was positively glorious! I wasable to gather a total of 7 hours of 30minute subs. Calibration and stackingwere done with CCDStack, and process-ing was completed using PixInsight, withjust minor touch up done in PS to com-plete the work. Imaged with my ST-8300C on the pier mounted EdgeHD1100.

Pictured in this image is a lesser knowntrio of galaxies in the Virgo Cluster. Thecenterpiece of the trio is NGC 4216,

located about 40 million Ly away, whilethe upper left galaxy is NGC 4222(approx. 44 million Ly away), and thegalaxy at the lower right of the image isNGC 4206 (further away at approx. 65million Ly). NGC 4216 is 100,000 Lyacross, making it approximately the samesize as our Milky Way Galaxy. So, if youhappened to be staring through a tele-scope some 40 million Ly away and justhappened to catch a nearly edge-onglimpse of the Milky Way galaxy, itwould probably look a lot like NGC4216. Ken Crawford's November, 2010,APOD entry shows that NGC 4216apparently continues to experiencegrowth by cannibalizing nearby satellitegalaxies, such as PGC 39247, located justabove the left side of NGC 4216. Thereare also many other faint fuzzies visiblein the image. In fact, I originally plannedto crop the image to center the trio ofgalaxies, but after processing I could seemany small, faint, distant galaxies thatwould have been lost (including what

appear to be a couple of very distant clus-ters near the image's lower right edge) soI decided to forego the crop.

I always find it interesting to see whatwas happening here on good ol' TerraFirma at the time other celestial objectsare shedding forth their light. So, consid-er NGC 4206 (lower right galaxy), locat-ed about 65 million Ly away. When itwas sending all those photons our waywhich we're collecting today, Earth wasexperiencing the last great biologicalextinction event, at the end of theCretaceous Period, which resulted in theloss of the dinosaurs as well as nearly50% of all the world's species. The causeof this event is uncertain. The top twotheories involve the impact of a massivecomet or asteroid near what is nowMexico's Yucatan Peninsula, or excessivevolcanism. The geologic record indicatesthat both of these events occurred around65 million years ago.

P a r t i n g S h o t s


Jon Talbot: M83 (top) and NGC 6942 & open cluster NGC 6939: Both images taken at the Texas Star party 2016 with a

Stellarvue SVS 130 f/5 refractor and QSI 583 CCD camera on a Paramount MYT mount and processed using PixInsight.M83 - is also known as the Southern Pinwheel galaxy (NGC 5236). It is a barred spiral galaxy approximately 15 million lightyears away in the constellation Hydra. It is one of the closest and brightest of its type and is visible with binoculars.NGC 6942 & 6939 are located on the border of the constellations Cygnus and Cepheus. NGC 6946 shines through a dense starfield and background dust of our Milky Way, which does dim its light. Also known at the “Fireworks galaxy” as 8 supernovaehave been observed in it over the last 100 years. The star cluster NGC 6939 in the constellation Cepheus lies within the MilkyWay, but makes for a nice visual and photographic pairing.


Bill Williams: NGC 6888 - The Crescent Nebula: I have so much astrodata to process - what a good problem to have! But what to tackle - (A). LRGB "natural color" data or

(B). narrowband data (NB)???? I chose (C). both. By this I mean I chose to process an image for which I have both LRGBand NB data aplenty, namely the Crescent Nebula (NGC6888) in Cygnus. I created the image using the "layer stack- clip-ping mask" method in Photoshop for the NB data and blended it with "normalizing" LRGB data to render better color tonal-ity than would be possible with NB data alone. My image consists of 11 hours of oxygen III (OIII) data and only 3 hours ofhydrogen-alpha (H-a) data, both 1x1 with the RCOS from Chiefland Astronomy Village. H-alpha was assigned (colormapped) to red and OIII to both green and blue. Guess there isn't much sulfur II (SII) in there so I didn't shoot any. TheLRGB exposures totaled a few hours.

The Crescent Nebula is one of the most imaged deep sky objects. There have been at least 7 APODs in the last 15 years orso. There have also been a lot of great scientific articles written about the Wolf-Rayet star WR136 in the Crescent. One arti-cle discusses a huge bubble around the Crescent Nebula (see below). The only other WR star ejecta nebula I can recall imag-ing is Thor's Helmet (NGC2359) in Canis Major (2010) from CAV with Tony Hallas. I would love to image Thor's some-day at a greater altitude in the sky and add some LRGB data. One more thing on a very long bucket list!

http://chandra.harvard.edu/photo/2003/ngc6888/ -- Terrific article about WR136 inside Crescent!

http://arxiv.org/pdf/1006.0625.pdf -- article about searching for ejecta nebulae around WR stars!


Bill Williams - AboveComet C/2013 X1(PANSTARRS) came with-in 1 degree of the HelixNebula in Aquarius themorning of June 4th!Although low in the skyjust before dawn, what abeautiful sight! This is a 40minute LRGB taken withVixen 100mm f/3.8 refrac-tor and SBIG 11K CCDCamera binned 2x2.Saturday morning, thecomet will lie within one-half degree from the Helix,a scene we hope to alsocapture!!

Barry Riu - RightOn April 21st, Barry cap-tured this huge archingProminence with his Lunt152mm solar scope


Barry Rui: Imaged Mercury’s 3032 mile disk as it transited the Sun -on May 9 at 9:23 AM. It was imaged witha scale of 56 miles per pixel. Below Barry overlaid an image of earth to scale for comparison.

78 www.AmateurAstronomy.com

amateur astronomy magazinetomclark.powweb.com/aamag_upload/is91sum16/aam_91summ.pdf · amateur...

Documents