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”
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