Lifan Wang Texas A and M, USA/ Chinese Center for Antarctic Astronomy, (Director), Nanjing, China

1. News on Developing Dome A as an International Astronomical Observatory and Progress on the Successful Traverse (driving in!) by the Polar Research Institute of China and the Chinese Center for Antarctic Astronomy HOU Teacher Conference, June, 2008 Carl Pennypacker, LBNL, UCB

2. Collaboration Lifan WangTexas A and M, USA/ Chinese Center for Antarctic Astronomy, (Director), Nanjing, China Huigen Yang , Y. LiPolar Research Institute of China Xiangqun Cui, Xiangyan Yuan Nanjing Institute of Astronomical Optics and Technology, China Jingyao Hu, Zhaoji Jiang, Xu Zhou National Astronomical Observatories of China Feng Longlong, Jun Yan, Zhu Zhenxi Purple Mountain Observatory, China Zhaohui Shang Tianjin Normal University, China Michael Ashley, Colin Bonner, Jon Everett, Jon Lawrence, Daniel Luong-Van, Suzanne Kenyon, Shane Hengst, John StoreyUniversity of New South Wales, Australia Anna Moore, Reed Riddle, Tony TravouillonCalifornia Institute of Technology, USA Craig Kulesa, Chris Walker University of Arizona, USA Don York University of Chicago, USA  Nick Tothill University of Exeter, UK  Bob Tripp LBNL, USA Carl Pennypacker LBNL, Space Sciences Laboratory, USA

3. Outline 1) More rationale on goals of this traverse 2) The Traverse itself • Closer inspection of some of the instruments on this traverse. 4) Antarctic Schmidt Telescope Progress

4. From Lifan’s Talk: Chinese Center for Antarctic Astronomy • Dome A Site Survey-Pilot system - 2007 and 2008 Traverse - Survey site, determine height of boundary layer, measure seeing - Do Science with C-STAR -- limiting magnitudes of about 17 (five sigma) in ten seconds, stack images, • Antarctic Schmidt Telescopes x 3 (AST3) -- being built now for 2009 traverse! - 3x 0.5 meter telescopes, 10K x 10K CCD’s, 1”per pixel - ~ 100 good SNe per year, ~1 earth mass planet a year due to micro lensing, hello- seismology, etc. •Dome A Survey Telescope (4 - 6 meters ~> 12 - 18 meter in Chile or Mauna Kea) 10,000’s SNe per year, etc. • Infrared Telescopes -- e.g., very high redshift studies.

5. (Breath-taking) Timeline of Astronomy Ideas: June, 2006: Beijing Dome C - Dome A meeting January 2007: Go decision from Purple Mtn. Observatory, PRIC, NAOC, and Chinese National Academy of Sciences -- Astronomy becomes part of China’s PANDA IPY proposal November, 2007: Xue Long leaves Shanghai, loaded for traverse (mostly --> on to Freemantle November 30, 2007: Departs Freemantle, Australia to load PLATO December 10, 2007: Arrive at Zhongshan Station December 17: PLATO airlifted to Progress Airfield, tank filled December 22: Begin Traverse January 12 : Arrive at Dome A February 21 , Depart Dome A

6. Why is the excitement? Example 1 Above A boundary Layer(at Dome C ~ 30 meters) seeing is amazing :

7. From Poisson Statistics: Easy arithmetic, for point sources against a sky background, ignoring detector noise: “Effective” Aperture diameter a 1/(seeing disk diamter) Hence, a 5 meter at Dome A should behave like a 15 meter in Chile.

8. How to Rise Above the Boundary Layer (if needed) with a translation-only tower ~ 1 micron rotational movement/tilt due to wind -- two studies by Robert Hammerschlag, Netherlands -- based on Dutch Open Telescope Tower on La Palma

9. With Good Seeing and 4-meter optics, you can do pretty well: Exposure time -- seconds

10. Seeing Review: Ground-based Astronomical Seeing, due to high frequency temperature fluctuations in the path of the beam is often sub-divided into three components, with different physical heights along path: Dome Seeing 2) Boundary Layer seeing 3) “Free atmosphere seeing in Jet Stream

11. Dome A: No Dome Seeing 2) Boundary layer is low 3) No Jet Stream (polar vortex protects us!)

12. Characteristics of the Collaboration: • Support a wide and useful set of astronomy projects, in the price range of $0.001M to $100M • Do amazing science at lower cost than other sites or orbits (planet finding, deep imaging, infrared imaging, sub-millimeter astronomy, etc.) • Be a nimble collaboration, that can change goals, science, detectors, many times in response to science and technology opportunities -- aim for Evolution ---> Revolution! • Do projects with 2 to five year horizons • Build on the profound commitment of China to Dome A (both for Polar Work and astronomy -- “Dome A is the Best Mountain in China”) • Good governance, collaboration rules, clear path to joining collaboration • Very respectful, smart collaboration with good resources, moving incrementally and carefully. • China’s National Funding agencies, Academy of Science, broader government. In addition, many people of China are supportive of this effort, along with their support for science and technology in general. (hint, hint US Congress)

14. More Details and Familiar Landmarks

15. Google Earth View (rotated)

16. Google Earth View (close-up and rotated)

17. Progress • Nov 30: Xuelong departs Fremantle • Dec 10: Xuelong arrives Zhongshan • Dec 17: PLATO airlifted to Progress airfield

20. Dome A Office

21. Goodbye ‘til Next January

23. Height of Boundary Layer and Ground Seeing vs. Wind Speeds from Swain/Gallee simulation

24. How much better is Dome A than South Pole, Dome C??? PLATO Dome A The annual vector mean winds from Polar MM5 Dome A 4100 altitude highest driest coldest calmest Wind speed (m/s) Courtesy A. Monaghan, Byrd Polar Research Centre

25. Height of Boundary Layer

28. South Pole Temperature Profile

29. Temperature

30. Dome A Temperature Profile

31. Site testing Atmospheric parameters for astronomy • Turbulence (SNODAR) • Boundary layer height, distribution and variability • Upper atmospheric distribution • Sky emission (Gattini) • Auroral spectral intensity and distribution, (visible and infrared) sky background versus sun/moon elevation • Sky transmission (Pre-HEAT) • Transparency and noise in long wave (sub-millimetre) windows • Cloud (Gattini ASC) • Cloud cover statistics and distribution • Science (C-STAR) • Optical transients: variable stars, transits, micro-lensing, GRB, etc

32. PLATO Concept design Feb 07 PLATO (PLATeau Observatory) • Deployment Jan 2008 via PRIC traverse • Completely autonomous and self powered • High reliability control system • Low bandwidth communications • Set up 2 weeks 2 people • Dual module design 30 m tilt tower solar panel array 2 m 50 m engine module Instrument module

33. PLATO Delivery Nov 07 PLATO (PLATeau Observatory) • Deployment Jan 2008 via PRIC traverse • Completely autonomous and self powered • High reliability control system • Low bandwidth communications • Set up 2 weeks 2 people • Dual module design 30 m tilt tower solar panel array 2 m engine module Instrument module

34. PLATO design • Provides Power, Shelter, and Control for Antarctic instrumentation • Two modules: • Power module • Instrument module • Separated by 50 meters • Modified shipping containers • Shipping containers? • Logistics • Manufacture • Durability • Two modules? • Manufacture and testing • Diesel contamination • Acoustic • Water vapour • Expansion

35. Instrument module Iridium antennas Nigel port webcams Gattini all-sky MASS port Gattini SBC Pre-HEAT spare ports CSTAR, SNODAR, Sonics located externally on snow surface

36. IM layout

37. IM Control • Supervisor nodes (x2) • PC104 computer: • 400 MHz Celeron • 256MB SDRAM • 2 x 4 GB USB flashdisc with read only filesystem on master • Lithium back-up battery • CAN microcontroller: • ATMEL development board • Software wakey-wakey and handshaking • Custom power-switching interface PCB • Iridium L band transceiver • SDB and direct-ssh • Externally located low-temperature antenna • Thermally regulated enclosure

38. SNODAR • Surface layer Non-Doppler Acoustic Radar • Designed and built by UNSW / Univ Aukland • high frequency piezo-electric transducer with 1.2 m dish • Measures: high resolution (1 m) Cn2 in boundary layer (5-100/800 m) • Mounting: externally on snow surface • Power: 30 W (internal) + 100 W (external) • Weight: 300 kg (total) • Installation: 1 day

39. SNODAR South Pole 2001… • output … Dome C 2003 …and Dome A 2008 ???

40. Collaborators… E. Aristidi Uni. Nice M. Ashley Uni. NSW R. Briguglio Roma/La Sapienza M. Busso Uni. Perugia M. Candidi PNRA G. Cutispoto Catania E. Distefano Catania J. Everett Uni. NSW S. Kenyon Uni. NSW J. Lawrence Uni. NSW (co-PI) D, Luong-Van Uni. NSW A. Phillips Uni. NSW B. Le Roux INAF:Arcetri R. Ragazzoni INAF:Perugia L. Sabbatini Roma/La Sapienza P. Salinari INAF:Arcetri J. Storey Uni. NSW M Taylor Uni. NSW G. Tosti Uni. Perugia T. Travouillon Caltech Dome A • G. Allen Solar Mobility • M. Ashley Uni. NSW • T. Bedding Uni Sydney • C. Beichman JPL/MSC • D. Ciardi MSC • X. Cui Nanjing/NAO • P. Espy BAS • J. Everett Uni. NSW • L. Feng Purple Mountain Obs • J. Hu NAO/Beijing • Z. Jiang NAO/Beijing • C. Kulesa Steward Obs • J. Lawrence Uni. NSW • Y. Li PRIC • D. Luong-Van Uni. NSW • W. Qin PRIC • C. Pennypacker Livermore/Berkeley • R. Riddle TMT (co-PI) • W. Saunders AAO • Z. Shang Tianjin • D. Stello Uni Sydney • J. Storey Uni. NSW • B. Sun PRIC • N. Suntzeff Texas A&M • N. Tothill Uni Exeter (co-PI) • T. Travouillon Caltech (co-PI) • G. van Belle ESO • K von Braun MSC • L. Wang Texas A&M • J. Yan Purple Mountain Obs • H. Yang Purple Mountain Obs • X. Yuan Nanjing/NAO • Z. Zhenxi Purple Mountain Obs • X. Zhou NAO/Beijing Dome C Gattini-DomeC are part of the IRAIT site testing campaign (Tosti et al)

41. Why Gattini? 0.27” mean seeing (l=550nm) above boundary layer at Dome C (Lawrence et al, Agabi et al) and likely Dome A Groups want to take the next step2m+ aperture OIR at Dome C BUT optical sky brightness (including twilight and aurora) largely unquantified GATTINI cameras are giving first estimate of these parameters essential for “BIG OPTICAL ASTRONOMY”

42. Gattini DomeA SBC camera(SBC=Sky Brightness Camera) • Transit camera pointed to South Pole • General features • 2.8 deg x 2.8 deg FoV • 5.1 arsec/pix • Sloan g’, r’, I’ filters • Technical features • Apogee Alta USB CCD camera • 2000x2000 pixels • Thermally controlled to ~ -40C • Objective aperture : 75 mm • Objective focal length: 300 mm Self-calibrating on stars

43. Gattini-DomeA Allsky • Transit camera pointed to Zenith • General features • ~90deg x ~90 deg FoV • Bessell B, V, R and long pass red for OH emission • Technical features • Apogee Alta USB CCD camera • 2000x2000 pixels • Thermally controlled to ~ -40 0C • Objective aperture : ~3.5 mm Self-calibrating on stars

44. SBC camera works! Raw image of April 8th 2006 at 23:48 40sec exposure Raw image of July 2nd 2006 at 00:03 40sec exposure

45. Raw image of March 29th 2006 40sec exposure Allsky works ! LMC SMC Satellite trail

46. Field coverage of SBC SBC images 6deg by 4deg centered on SP ~40 sec exp time – no star trails (though not mandatory) Identify bright stars and use for flux calibration of sky pixel intensity Produce 2D sky brightness map every 20 mins Side project- variable star monitoring?

47. Gattini-Allsky • Transit camera pointed to Zenith • General features • 110deg x 80 deg FoV • Limiting magnitude: mV16/arcsec2 • Full CCD spectral response, no filter • Technical features • Apogee Alta USB CCD camera • 1600x1200 pixels • Thermally controlled to ~ -30 0C • Objective aperture : ~3.5 mm Self-calibrating on stars

48. Sky Brightness 6.5 months continuous data from the all sky camera gave initial brightness estimates (2006 winter season) Brightness values are uncalibrated values across the visual spectrum (this is changed for 2007 data) Icing issues with the SBC meant the all sky camera was more appropriate for preliminary analysis (solved for 2007 data)

49. Sky brightness with no moon contribution M(θ) = Ms - 10(20.32 - 11.66θ) The sun! -13deg -18deg (-39deg) moon zenith distance (rad) UNFILETERED Magnitude (mag/arcsec2) Astronomical twilight sun elevation > -18˚ Astronomical darkness sun elevation < -18˚ (-13deg) sun zenith distance (rad)

50. Sky brightness with no sun contribution M(θ, Φ) = Mm - Φ10(-0.97 - 0.58θ) The Moon! Moon phase: Φ = 0% Φ = 50% Φ = 100% moon phase (%) Magnitude (mag/arcsec2) above horizon below horizon moon zenith distance (rad) (+46deg ZD) (-39deg ZD)