Telescope Projects at Steward ObservatoryWork in Progress

Astronomical Society of New York Union College

Saturday, 24 October 2009

Peter WehingerSteward ObservatoryUniversity of Arizona

Casting a 6.5-m Mirror for San Pedro Martir

Steward Observatory Mirror Lab

A World Class Site: San Pedro MartirBaja California, Mexico

Peter Wehinger

HexagonalColumns

ofAl2SiO5

HoneycombStructure

Light-weightSpun-castMirrors

Casting in Progress –

26 Aug 2009

SPM 6.5-mMirror

The Principals

UNAMINAOE

UC BerkeleyUC Santa

CruzU Arizona

San Pedro MartirA World Class Site

Peter WehingerSteward Observatory

SOML Casting Event – 6.5-m Mirror26 August 2009

SPM

Tucson

Ensenada

San Diego~ 600 km

Baja California and the Sonoran Desert

380 km

SPM Obs

Pico del Diablo

Meling Ranch Airfield

Road to San Pedro Martir

60 km

40 km

Climatic & Seeing Conditions

Clear Sky Statistics

• Photometric ~ 63% (Tapia et al)

• Satellite Imaging ~ 73% (Erasmus et al.)

• Spectroscopic ~ 81% (Tapia et al.)

Seeing Statistics

• Median Seeing ~ 0.48 arc sec

• Mean Seeing ~ 0.57 arc sec (FWHM)

• 25th Percentile ~ 0.37 arc sec

LBT

Kitt Peak

Lick

Palomar

MMT

Lowell

NIGHT SKY IN THE DESERT

SPM Sky brightness B ~ 22.3 mag/sec2

PHXLA

TUC

HER

N

San Pedro Martir

Ensenada

Yuma

San Felipe

San Diego

Tijuana

SPM

Sky Brightness at San Pedro Martir

Darker than B ~ 22.3 mag/sec2

300 km

300 km

N

Night Sky Spectrum on San Pedro MartirIn

tensi

ty (

erg

/s/c

m2/A

)

(A)

Remarks about SPM Night Sky

• Integrated Light of Night Airglow Green Line [OI] 5577visible to ~10-15 deg above horizon

• Arcturus – steady, no scintillation (twinkling)

• Naked-eye limit at least ~ 7th magnitude

• 10-12 of brightest galaxies in Virgo Cluster - visible

• SPM has darkest night sky – Compared with other sites Arizona, Chile, Hawaii, Himalayas

Possible Air Field at Vallecitos ~ 5-6 km from telescopes

2425 m

2434 m

2 km

LBT

LARGE BINOCULAR TELESCOPE

Site: Mt Graham, Arizona

Two 8.4-m f/1.1 Mirrors

StewardObservatoryMirror Lab Casting Bay

6.5-m

8.4-m

8.4-m

LBT Edge-to-Edge ~ 22.4 m, Equivalent Circular Aperture ~ 11.8 m

30 m

NGC 6946 with 8.2-m Subaru

NGC 6946 with 8.4-m LBT

GMT

GIANT MAGELLAN TELESCOPE

Site: Las Campanas, Chile

GMT• seven 8.4-m Mirrors

• 21.5-m Circular Aperture

• 25.5-m Edge to Edge

Graphics by Todd Mason

GMT Partners as of Oct 2009 -

• Carnegie Institution of Washington• University of Texas at Austin• Texas A & M University• University of Arizona • Australian National University • Astronomy Australia Ltd. • Harvard University • Smithsonian Institution• Korea Astronomy & Space Institute

+ 1-2 others considering joining

Mirror Lab Founder, Roger Angel

inspects 8.4-m mirror for GMT

GMT-1– polishing at ~ ±0.5Oct 2009

Final figure will be ±10-20 nm, 400x smoother

When GMT is completed in ~ 10-12 years

• What will be found…?

• Remember Hale & Wickliffe Rose

• Again there will be many surprises..!

Three Planets

b, c, & d

Imaged around

Star HR 8799

Light from central star is suppressed

Discovery Announced

14 Nov 2008

Gemini 8.2 m

Phil Hinz et al. Steward Observatory

LSST

LARGE SYNOPTIC SURVEY TELESCOPE

Site: Cerro Pachon, Chile

Founding Partners (2003)

• University of Arizona• Research Corporation• University of Washington• NOAO• + 18 other institutions (as of 2008)

Large Synoptic Survey Telescope

LSST Optical Layout

8.36 m

6.28m

4.96 m

3.4 m

64 cm

Primary f/1.25

Secondary

Tertiary f/0.8

Focal Plane

Design: L. Seppala, LLNL

Filters

Field Flattener

Large Synoptic Survey Telescope

Project Overview & Goals

• 10-sec exposures ~ 24 mag.• 3.5 Gpix/image – 10 sq. deg • 30-40 Terabytes per night• Entire sky surveyed in 4 nights

• Search for Near-Earth Objects• Survey the Kuiper Belt • Probe dark matter

• Many Surprises • Serendipitous Discoveries

64 cm

LSST

8.4-m Primary Mirror

22 October 2008

Lifting off oven floor

Weight ~ 52 tons

Glass ~ 26 tons

LSST

8.4-m Primary Mirror

22 October 2008

During move from oven to holding ring

Weight ~ 103,000 lbs

Glass ~ 52,000 lbs

Ground-Layer Adaptive Optics

Recent Results on MMT

Planet found around the Nearby starPictoris

ESO 8.1-m Telescope

The MMT multi-laser GLAO system

Laser type 2 x doubled YAG (15 W each)

Wavelength 532 nm

Pulse rep rate 5.2 kHz

Average power 30 W

Launch location Behind secondary mirror

Number of beacons

5, arranged like a pentagon

Enclosed field of view

2 arc minutes

Beacon type Rayleigh scattering

Range gate 20-29 km, dynamic refocusing

MMT results: M3

Open loop, Ks filter, seeing 0.70”

Logarithmic scale

110”

MMT results: M3

Closed loop GLAO, Ks filter, seeing 0.30”

Logarithmic scale

110”

http://apod.nasa.gov/apod/image/0811/fomalhaut_hst_lab.jpg

NGC 2770 – First Light Binocular Image with LBT

11 Jan 2007

Supernova

Gamma-Ray Burst

Magellan 1 6.5-m Telescope (Baade) Las Campanas Observatory

VLT UT1 8-m Telescope & FORS 1: ESO

Paul Groot, Harvard-Smithsonian Center for Astrophysics

Jerome Orosz, University of Utrecht

1

Optical Images of X-ray Nova XTE J1550-564