roanoke valley astronomical society · volume 33—number 1 january 2016 roanoke valley...
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Volume 33—Number 1 January 2016
Roanoke Valley Astronomical
Society Amateur Astronomy News and Views
In Southwestern Virginia
RVAS NL— January 2016— Pg 1 of 9
By Bill Dillon, Secretary
Unseasonably warm weather and flat tires notwith-
standing, our December 2015 meeting and Winter So-
cial was held as scheduled. With our President, Dan
Chrisman, still recovering from surgery and uncertain to
attend, and our Vice President, Rand Bowden, detained
on the road with a flat tire, Immediate Past President
Michael Good stepped in to open the meeting. There
were 27 members and guests in attendance as Michael
first directed the group to observing reports. In spite
of relatively dark clear skies and comfortable tempera-
tures recently, there were few observing reports. Com-
et Catalina was a tempting target for a couple of the
members present at the meeting who reported seeing
an indistinct, mostly hazy object. It was about this time
that both President Dan Chrisman and Vice President
Rand Bowden joined the meeting.
Michael then turned the meeting over to Frank Bar-
atta. Before proceeding with the beginning of the Win-
ter Social program, Frank introduced our newest mem-
ber, Mr. Edward Leonard who was welcomed by a round
of applause. Frank then officially opened Winter Social
2015. With holiday music playing in the background,
Frank divided the attendees up into three anxious
groups (amateur astronomers being naturally somewhat
reserved and shy). The three groups were called on to
act and “speak” the part of Betty Boop, Popeye and
The Big Bad Wolf as Frank read a “story”. Participation
started tentatively, but by story’s end, all attendees
were fully engaged. Frank turned the meeting back over
to Michael who then invited all to visit the table loaded
(Meeting Continued on page 2)
December RVAS Meeting Notes
Betty Boop, Popeye and the Big Bad
Wolf---Celestial Objects? Not!
RVAS members and guests gather to sample the treats and beverages everyone has brought to share at the Social.
Photo by Carolyn Baratta
The Roanoke Valley Astronomical Society is a membership organization of amateur astronomers dedicated to the pursuit of observational and
photographic astronomical activities. Meetings are held at 7:30 p.m. on the third Monday of each month. See calendar on last page of news-
letter for location. Meetings are open to the public. Observing sessions are held one or two weekends a month at a dark-sky site. Yearly dues
are: Individual, $20.00; Senior Individual, $18.00; Family, $25.00; Senior Family, $22.00; Student, $10.00. Articles, quotes, etc. published in the
newsletter do not necessarily reflect the views of the RVAS or its editor.
Officers/Executive Committee/Editor/Webmaster Dan Chrisman, President ([email protected] )
Rand Bowden, Vice President ([email protected])
Bill Dillon, Secretary ([email protected])
Jeff Suhr, Treasurer ([email protected])
Carol Mesimer, Member at Large ([email protected])
Michael Good, Immediate Past President ([email protected])
Frank Baratta, Past President ([email protected])
David E. Thomas, RVAS Newsletter Editor ([email protected])
Roger Pommerenke & David E. Thomas, Webmaster ([email protected])
RVAS web page: http://rvasclub.org
with tasty goodies. Everyone filled up their plates while
being treated to more holiday music.
While the tasty treats were being consumed, Frank pre-
sented his “What’s Up” for the calendar month of Jan-
uary 2016. Highlights for the month include the Pleia-
des and Orion visible nearly overhead at full darkness;
Sirius making a brilliant appearance by month’s end; Ju-
piter rising by mid-month at 10:00 p.m.; the “Winter
Hexagon” comprised of Capella, Aldebaran, Rigel, Sir-
ius, Procyon, and Pollux fully in the eastern sky at full
darkness; and deep sky viewing of open (galactic) star
clusters and nebulae. For Cahas observing on January
1st, 2nd, 8th and 9th, we will have a last quarter moon on
January 2nd, and a New moon on January 9th.
Comet Catalina will continue to be a target for many
during the month as it tracks from SE to NW across
the sky. At present the comet shines at about magni-
tude 6.5 making it a challenge in all but very dark skies.
Concluding his presentation, Frank mentioned a challeng-
ing observational opportunity, namely the lunar occulta-
tion of Aldebaran occurring on January 19, beginning at
approximately 9:21 p.m. EST.
While the attendees “scarfed up” the last of the deli-
cious treats available, Mark Hodges demonstrated the
results of his latest “gadget”, a Ricoh Theta S camera.
(Meeting Continued from page 1)
(Meeting Continued on page 3)
Frank Baratta compares the mid-December and mid-January night
skies during his monthly,”What’s Up” short program.
Photo by Carolyn Baratta
Mark Hodges demonstrates the imagery produced by his latest “gadget”, a Ricoh Theta S camera.
Photo by Carolyn Baratta
RVAS NL— January 2016— Pg 2 of 9
June 28, 2015 June 29, 2015
June 29, 2015
Get Connected!
Want to be more in touch with other RVAS members? Join the RVAS Yahoo Group! Share
last-minute observing plans, articles, ideas, astrophotos—you name it. You’ll need to have or
create a Yahoo email address. Click the link below. Once logged in, provide the information
requested, including your real name since the group is only for members and those invited.
You’ll receive an acknowledgement from the moderator.
https://groups.yahoo.com/neo/groups/RVAS_Club/info
For assistance, call the RVAS Message Line (540-774-5651). We’ll have you connected in no
time!
This little camera mounted on a tripod, controlled by a
cell phone app, is capable of 360 degree stills or videos.
The meeting attendees found the photographic exam-
ples shown by Mark of what the camera can do to be
fascinating.
It was now time for what has become a club tradition:
the annual RVAS slideshow. First suggested by former
Vice President Sharon Stinnette, our 2015 edition was
the fourth consecutive yearly pictorial review of mem-
bers, speakers and friends caught in the midst of club
meetings and other astronomy activities. As always,
this evening’s show quickly evoked a series of quips from
the audience, adding witty captions to the humorous
scenes appearing on the screen. In all, some 150 images
were displayed in just over 12 minutes and offered a
merry end to another successful year for the club.
Thanks to all who chronicled our activities with their
photos; in particular, to our chief photographer, Carolyn
Baratta, whose images comprised the bulk of the show,
but also to Frank Baratta, Dan Chrisman, Michael Good
and John Goss, who also contributed to the show.
With a few minutes remaining, Michael called on Frank
for the meeting’s concluding activity, a game of “Astro-
Anagrams”. One at a time, Frank flashed on the screen
three astronomy- or space-related word jumbles to be
unscrambled, with a prize to be awarded to the first to
do so for each anagram. The first proved the most chal-
lenging and remained unsolved, but the second and third
were correctly answered by Bill Dillon and Fred Davis,
respectively, for which each received a DVD about the
New Horizons mission to Pluto.
Michael drew the meeting to a close a few minutes after
9:00. A good time had been had by all!
(Meeting Continued from page 2)
(Meeting Continued on page 4)
Still recuperating from his recent surgery, RVAS President Dan Chrisman (left) shares a moment with Vice President Rand Bowden during the Social.
Photo by Carolyn Baratta
RVAS NL— January 2016— Pg 3 of 9
Additional Images from the
Winter Solstice Social
Panoramic photo by Michael Good; all others by Carolyn Baratta.
(Meeting Continued from page 3)
RVAS NL— January 2016— Pg 4 of 9
Albireo:
https://flic.kr/p/BaMo3h
Albireo would not look like this in your high-powered eye-
pieces, but it is reasonably split at this image scale and
the contrasting colors are quite evident. I feel that for
this subject at least, the diffraction spikes are fitting.
M16:
https://flic.kr/p/BuWNfR
The "Pillars" are surprisingly visible. Of course, this is
what they looked like almost 7000 years ago, not how
they would look now, in our real time. Some people think
that they may actually be gone by now; their interpreta-
tion of some infrared imaging suggests that a shock wave
had been on its way to rip this apart.
Member Observation By Clem Elechi
M20:
https://flic.kr/p/BWUMBq
With this one, I relearned a lesson that we all know: the
atmosphere can be a hugely distorting lens. This is why
some imagers and observers use an atmospheric disper-
sion corrector. As the object sank lower in the sky, the
stars got bigger and more distorted. I could not use the
last few frames at all.
NGC6888:
https://flic.kr/p/BKHk6s
This wide view shows much of the nebulosity in that area
of the sky.
Cone Nebula area:—>
https://flic.kr/p/BN2gsM
Beside the Cone nebula, other objects of interest in this wide view
include the Fox Fur nebula and Hubble's Variable nebula. Hubble's
Variable nebula is variable in appearance and is reportedly the
first light image of the Palomar telescope by Edwin Hubble him-
self.
RVAS NL— January 2016— Pg 5 of 9
RVAS NL— January 2016 — Pg 6 of 9
MESSIER PROGRAM OBSERVING
The Messier objects for January are: M33, M34, M52,
M74, M76, M77, M113.
The observing session will be held at 6:30 pm, Friday
January 8th at Cahas knob overlook, MP 139 on the
Blueridge parkway.
Club members are welcome to join in the Messier hunt at
any time. (Using a scope or binoculars)
Images by NASA
Are You Receiving Your Newsletters
and Other Club Emails?
To save having to download newsletters from our website, these and other items of interest are emailed to
members. If you have not been receiving these items by email, please let us know by calling the RVAS Mes-
sage Line at 540-774-5651. Please also check whether your spam blocker is intercepting our emails.
RVAS 25 years ago
The Newsletter from January 1991 previewed upcoming
highlights for the year including a penumbral solar
eclipse on January 29th and a partial eclipse occurring
nearly eleven months later on December 21st. Planetary
observers were looking forward to a triple conjunction
of Venus, Jupiter and Mars on June 18th, as well as
“Jupiter’s January opposition, with a disk almost 45 arc
seconds across, and Mercury’s March/April evening ap-
parition.”
“Finding your way around the sky” focused on the Win-
ter Hexagon of Capella, Aldebaran, Rigel, Sirius, Procy-
on, and Pollux (mnemonically speaking, “CAPtain AL’DE
RIGging Seems PROperly POLished”).
The Welcome Mat introduced a new member from Lex-
ington, Mr. Ken Harris, and the Member Profile report-
ed on Roger Poe from Hillsville, Virginia in Carroll Coun-
ty. Roger, a member since 1988, often participated in
observing sessions at Carter’s farm using his 8” Coulter
Dobsonian and 9x63 “Little Giant” binoculars.
RVAS 10 years ago
(The January and February 2006 Newsletters were
published in one issue in February)
The Newsletter’s lead article highlighted the RVAS
participation in “Enchanted Eve 2005/6”. This was the
Second Annual Enchanted Eve celebration taking place
in many locations in downtown Vinton to ring in the New
Year in a fun, family oriented atmosphere. The Club’s
location for the event was the front lawn of the Vinton
War Memorial, where Club members set up seven tele-
scopes open to the public. It was reportedly neither
very cold nor windy, with relatively clear skies, and as a
result, “close to 1000 people of all ages stepped up to
the eyepiece of a telescope, some for the first time in
their lives, and walked away excited by what they had
seen.” The “first customer” was a fifth-grader who
managed to spot Venus before the sun set. Other ob-
servers were treated to the Double Cluster in Perseus,
Mars, Betelgeuse, Rigel, the Orion Nebula, the Pleiades,
and Saturn among others.
The Newsletter also reported on the annual Winter So-
cial at the December meeting where 25 members and
guests were treated to a tableful of goodies.
RVAS from the Past By Bill Dillon
RVAS NL— January 2016— Pg 7 of 9
The moon, progressing along its
path around Earth, presents
the observer in southwest Vir-
ginia three exercises to ob-
serve effects of its elliptical
orbit. The first involves the
moon moving different angular
distances across the sky in
each twenty-four hour period.
When it is relatively close to
Earth, it travels slightly faster
and, therefore, moves a slight-
ly greater distance eastward
each day. The second activity
shows that when the moon is closer to Earth, it appears
larger in the sky, by as much as 13%. The third is the
phenomenon of libration.
The moon always maintains a constant rate of angular
rotation, meaning that it spins at the same speed, which
equals one full rotation for each complete trip around
our planet. However, its orbital velocity constantly
changes so that when it is near Earth, it moves faster
and a greater distance along its orbital path in each day
than when it is farther away. If its orbit traced a per-
fect circle, its velocity would remain constant and its
daily orbital motion would not vary. In other words, its
orbital angular velocity would be constant. But it is not,
and that is due to its elliptical orbit.
For an observer on Earth, this gives the effect of being
able to see, at times, slightly around either the moon’s
eastern limb or its western limb. Mare Crisium offers a
useful landmark near the eastern lunar limb where obvi-
ous effects of libration can be readily seen. Simply
mentally measure the distance from the eastern side of
Crisium to the limb and compare that to the diameter of
Crisium. At full libration, their ratio is nearly 0.60, that
is, the distance between Crisium and the limb is easily
more than one-half the diameter of Crisium itself. As
the moon swings towards greatest western libration two
weeks later, the ratio drops below 0.30, and the gap
becomes thinner.
When viewed straight on,
which never happens from any-
place on Earth, Mare Crisium
appears nearly circular. Due to
foreshortening effects from
being near the eastern rim, it
appears elliptical. As eastern
libration approaches, Crisium’s
ellipticity decreases, appearing
more circular.
Also at full eastern libration,
Mare Marginis and Mare
Smythii can be glimpsed as dark regions clinging to the
lunar limb. At other times, they don’t swing into view,
being hidden just beyond the moon’s edge.
The image of the 13 day old moon of November 24
doesn’t exactly line up with the image of the 5 day old
moon of December 15. There is a small amount of libra-
tion to the south, and the moon is 4% closer. Therefore,
Mare Crisium appears slightly larger and slightly shifted
northwards in the November 24th image.
Libration presents the strange case of an observer
standing on Mare Marginis seeing Earth rise a few de-
grees above the western horizon, then slowly set ten or
so (Earth) days later, remain just below the horizon for
another ten days, then take another three days to slow-
ly rise again. From Mare Crisium, Earth would always be
visible low above the western horizon, but would bob up
and down a few degrees during the lunar month. Unlike
the moon in our sky, it would remain in the same part of
the lunar sky. It would be seen changing phases as the
days proceed, just as the moon exhibits phases as
viewed from Virginia.
Why not follow the moon as it treks around the sky,
sometimes revealing features otherwise missed? The
moon and its motions are not as simple as they first
seem. Lunar libration looks looney!
Lunar Libration looks looney by John Goss
RVAS NL— January 2016— Pg 8 of 9
Use Our Message Line!
Want to check whether anyone is getting out on a scheduled observing session night or share that you’re
planning to do so? Have questions about the club or need its assistance? Call the RVAS Message Line,
540-774-5651, and leave a message or listen for any information available.
Monthly Calendar MONTHLY MEETING: January 18th, 7:30 p.m., Classroom A, 3rd floor, Center on
Church, Downtown Roanoke. It’s said that “Timing is Everything,” and nowhere is this more
true than in occultation timing. This evening, our own Paul Caffrey will highlight his involve-
ment and equipment used in this special pursuit. From mapping mountains of the moon to the
shape of distant asteroids, occultation timing can improve our knowledge of asteroid orbits
and even reveal hitherto-unknown asteroid moons. Join us for a look at this fascinating branch
of observational astronomy!
RVAS WEEKEND OBSERVING OPPORTUNITIES: Unless otherwise indicated, observing is held at Cahas Knob
Overlook, milepost 139 on the Blue Ridge Parkway.
-- Friday and Saturday, January 1st and 2nd. Sunset is at 5:14 p.m. Astronomical twilight ends at 6:47 p.m. The
Moon rises at 12:28 and 1:22 a.m., respectively.
-- Friday and Saturday, January 8th and 9th. Sunset is at 5:20 p.m. Astronomical twilight ends at 6:52 p.m.
The Moon sets at 4:23 and 5:20 p.m., respectively.
-- Friday and Saturday, January 29th and 30th. Sunset is at 5:42 p.m. Astronomical twilight ends at 7:11 p.m.
The Moon rises at 11:11 p.m. and 12:05 a.m., respectively.
-- Future Sessions: February 5th and 6th; February 26th and 27th.
ROANOKE CITY PARKS and RECREATION PUBLIC STARGAZE: Saturday, January 9th, 6:00 p.m., Cahas
Knob Overlook, milepost 139, Blue Ridge Parkway. Nonmembers must register with Parks & Rec. at 540-853-2236.
Members can call 540-774-5651 for information. (Next session: February 6th, 6:30 p.m., Cahas Knob Overlook, mile-
post 139, Blue Ridge Parkway.)
Astro-Quiz M35, one of winter’s grand star clusters, lies nearly on the ecliptic. About
how long ago would it have marked the location of the “vernal equinox”?
Answer to Last Month’s Quiz: His famous Belt is perhaps Orion’s most well
known star pattern, or “asterism”. Composed of Mintaka (δ Ori), Alnilam (ε
Ori) and Alnitak (ζ Ori), the Belt is also part of a lesser known asterism in
this constellation. Known mostly as “Venus’ Mirror” (but also called “Urania’s
Mirror”), it’s seen in the graphic at right. The Belt stars and Algiebba (η Ori)
comprise the diamond-shaped mirror when attached to its handle, the famous
Sword of Orion, home to the Great Nebula in Orion, M42. Have an answer to
this month’s quiz (or a future question and answer to suggest)? E-mail it to
RVAS NL— January 2016— Pg 9 of 9