Large optical telescopes on the Moon U Arizona, U British Columbia, U Houston, U Laval, NASA, ESA, CSA, ComDev R. Angel E. Borra J. Burge D. Eisenstein B. Foing C. Gosselin P. Hickson J-L. Josset P. Klimas K. Ma N. Rowlands E. Seddiki K. Seddon S. Sivanadam P. van Sussante S. Thibault S. Worden
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Large optical telescopes on the Moon
U Arizona, U British Columbia, U Houston, U Laval, NASA, ESA, CSA, ComDev
R. Angel E. Borra J. Burge D. Eisenstein B. Foing C. Gosselin P. Hickson J-L. Josset P. Klimas K. Ma N. Rowlands E. Seddiki K. Seddon S. Sivanadam P. van Sussante S. Thibault S. Worden
No absorption of light by the atmosphere No blurring of images by the atmosphere Night sky is about 1,000,000 times fainter from space, in the infrared
Why space?
Space Telescope Science Institute
Liquid-mirror telescopes on the Moon Paul Hickson RASC 2006-03-14 Page 8
Hubble Space Telescope (2.4-meter)
NASA
Liquid-mirror telescopes on the Moon Paul Hickson RASC 2006-03-14 Page 9
James Webb Space Telescope (6-metre)
NASA
Why large telescopes?
HST 2.4m JWST 6m Lunar 30m
NASA
Liquid mirror telescopes on the Moon?
NASA study, 2003-2006 CSA study, 2008
The surface of a rotating liquid is a paraboloid
Exactly what is needed to focus light
Lightweight Accurate Low cost
The Economist
Liquid-mirror telescopes on Earth
NASA Orbital Debris Observatory (3-m) UBC Large Zenith Telescope (6-m)
P. K. ChenChip Simons
Galaxies imaged with the LZT
Image moves continuously across CCD due to Earth’s rotation Charge being generated by photons is shifted electronically along the CCD columns at the same rate This prevents image smearing Data are read continuously all night long
Time-delay integration (drift scan)
LZT
Initial lunar telescope concept
Telescoping structure Deployable secondary mirror Inflatable sunshield Superconducting magnetic levitation bearing Low-temperature ionic liquid coated with metal film Polar location (track by rotating the camera)
Tom Connors
Optical design
Three-mirror anastigmat
F/1.5 20m liquid primary
2.4 m convex secondary 26 m above primary
4 m concave tertiary
20-arcmin field of view
Diffraction-limited resolution
Telescope structure technologies
Inflatable Truss Umbrella + tower system Assembly from modular units (truss+membrane)
Telescope structural analysis
Lightweight structura elements Deployable panels assembled by robot arm Membrane seals surface
Superconducting magnetic levitation bearings
Low power Passively cooled Active stabilization
Low-temperature liquids
Base liquid Liquid eutectic (Na-K or other) Ionic liquid Lithium Ammonia
Coated for higher reflectivity Interface layers (Cr, PEN) Vacuum deposition on large rotating mirrors
Polar location
Allows “tracking” by rotating the camera
South pole has permanently-shadowed craters
This allows the telescope to cool to 80K passively
Some peaks are permanently sunlit
Place solar collectors here and send power to the telescope Permanently shadowed craters at Lunar
South Pole (Shevchenko et al.)
The North Pole in winter15 km transmission line needed to bring power from sunlit areas to telescope
Which pole?
The south pole field contains the Large Magellanic Cloud The north pole field is less crowded
Observing strategy
18-year precession of Lunar axis sweeps out a 3.1-degree diameter circle
Total area accessible to the telescope is ~3 square degrees
Available exposure time is ~6000 hours
Study galaxies, black holes at any distance (>30 million galaxies)
Detect Earth-like planets to a distance of ~150 parsec (~1000 planetary systems)
Conclusions
20-metre liquid-mirror telescope is feasible
100-meter might be possible
Can make use of lunar base / outpost infrastructure for assembly
Assembly primarily by robotic means with on-site human supervision
Total Mass: 9400 kg Single Altair cargo lander
Smaller wide-field precursor telescope as first step?
Thank you!
More information:
Borra, E. F., Seddiki, O., Angel, R., Eisenstein, D., Hickson, P., Seddon, K. R. and Worden, S. P., Deposition of metal films on an ionic liquid as a basis for a lunar telescope, Nature, 447, 979-981 (2007).
Angel, R., Worden, S. P., Borra, E. F., Eisenstein, D., J., Foing, B., Hickson, P., Josset, J.-L., Ma, K. B., Seddiki, O., Sivanandam, S., Thibault, S., van Sussante, P., A cryogenic liquid-mirror telescope on the moon to study the early Universe, Astrophys. J., 680, 1582-1594 (2008).
Klimas, P., Rowlands, N., Hickson, P., Borra, E. and Thibault, S., Lunar liquid mirror telescope: structural concepts, Proc SPIE, 7732, 77322U-77322U-12 (2010).
Related Documents
