The Australian Centre for Space Photonics 2002 Proposal to the arc for a Centre of Excellence



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Mars and the Anglo-Australian Observatory



The Australian Centre for Space Photonics

  • 2002 Proposal to the ARC for a Centre of Excellence

  • Strong technical basis

  • Strong reasons for an Australian involvement

  • Withdrew from ARC proposal on applicability issues

  • Continuing work – maintaining vision – following different route to involvement



Mars

  • Diameter: 6790 km

  • Rotation period: 24.6229 hours

  • Polar inclination: 23.98°

  • Mass: 0.1074 Earth masses

  • Escape velocity: 5030 ms-1

  • Surface gravity: 3.73 ms-2

  • Albedo: 0.16

  • Atmosphere: 95% CO2, 3% N2

  • Surface pressure: ~10 hPa

  • Surface temperature: 130K – 300K

  • Solar orbit diameter: 1.4 AU

  • Distance from Earth: ~50Mkm to ~400Mkm



History



History



History



History



Mars

  • Recent opposition: only ~55 million km Earth to Mars

  • AAO observations using UKIRT in Hawaii, August 2003 obtained spectral ‘images’ in the NIR



Long slit spectroscopy



Long slit spectroscopy



Long slit spectroscopy



Long slit spectroscopy



Spectrographic analysis



Spectrographic analysis



Spectrographic analysis



Spectrographic analysis



Spectrographic analysis



Exploration of Mars

  • 1962 Two more Soviet flyby attempts, Mars 1 within 190,000 km

  • 1964 Mariner 3, Zond 2

  • 1965 Mariner 4 (first flyby images), Zond 3

  • 1969 Mariners 6 and 7

  • 1971 Mariners 8 and 9

  • 1971 Kosmos 419, Mars 2 & 3 (first landers)

  • 1973 Mars 4, 5, 6 & 7

  • 1975 Viking 1, 1976 Viking 2



Exploration of Mars

  • 1992 Mars Observer

  • 1996 Mars 96

  • 1997 Mars Pathfinder, Mars Global Surveyor

  • 1998 Nozomi launch

  • 1999 Climate Orbiter, Polar Lander and Deep Space 2

  • 2001 Mars Odyssey



Exploration of Mars

  • 2003 Nozomi arrival

  • 2004 Mars Exploration Rovers 1 & 2

  • 2005 Mars Reconnaissance Orbiter

  • 2005 Rosetta flyby

  • 2007 Mobile Scientific Laboratory

  • 2007 Netlanders-07

  • 2007 Remote Sensing Orbiter



Exploration of Mars

  • 2009 Smart Lander, Long Range Rover

  • 2009 Mars 2009 Communications Satellite

  • 2009 Netlanders-09

  • 2009 ExoMars-09

  • 2014 Mars 2014 (possible sample return)

  • 2015 Possible ESA manned mission

  • 2016 Mars 2016 (possible sample return)

  • 2019 Possible NASA manned mission



ExoMars-09

  • ESA exobiology mission scheduled to land a 220kg rover in 2009

  • ‘Pasteur’ instrument package



ExoMars-09

  • 180-day lifetime on surface

  • Search/sample/process cycle ~6 days



ExoMars-09

  • Opportunity for Australian involvement

  • ESA call to international community for interested parties to suggest instrumentation or other project support (due 14-May-03)

  • Large consortium with ACA and AAO as major partners submitted a proposal



ExoMars-09

  • “Prospector” proposal

  • Based on ACA expertise in most closely related search fields – detection of evidence of 3-4 Gyr old microbial life (Western Australia)

  • Two-fold involvement

    • Search strategy
    • Instrument proposal


ExoMars-09

  • Prospector instrument:

    • A NIR spectrometer boresighted to the stereo PanCam
    • Allows mineralogical assessment of potential drill/sample targets before the full investment of the expensive sample cycle


ExoMars-09



ExoMars-09



Communications -the bottleneck

  • Increasing number of missions

  • Evolution towards more data-intensive instrumentation

  • Increasing spacecraft data storage capacity

  • Greater reliance on public support for funding – greater sense of ‘presence’ requires greater data rates



Communications -the bottleneck

  • Radio (microwave) links, spacecraft to Earth

  • Newer philosophy - communications relay (Mars Odyssey, MGS)

  • Sensible network topology

  • 25-W X-band (Ka-band experimental) <100 kbps downlink





Communications Bottleneck

  • Current missions capable of collecting much more data than downlink capabilities (2000%!)

  • Currently planned missions make the problem 10x worse

  • Future missions likely to collect ever-greater volumes of data





Communications Bottleneck

  • Increasing downlink rates critical to continued investment in planetary exploration



Communications Energy Budget



Long-term Solution

  • Optical communications networks



Long-term Solution

  • Optical communications networks

  • Advantages over radio

  • Higher modulation rates

  • More directed energy

  • Analagous to fibre optics vs. copper cables



Lasers in Space



Lasers in Space

  • Laser transmitter in Martian orbit with large aperture telescope

  • Receiving telescope on or near Earth

  • Preliminary investigations suggest ~100Mbps achievable on 10 to 20 year timescale

  • Enabling technologies require accelerated development





Lasers in Space - challenges

  • Immature technology cf. radio

  • Cloud and other weather

  • Pointing and tracking

  • Signal acquisition

  • Reliability



Lasers in Space - challenges

  • Will not replace radio for all applications

    • Fast-manoeuvring spacecraft
    • Cheap, highly independent spacecraft
    • Emergency operations
    • Entry/descent/landing comms
    • Dusty/thick atmosphere environments


Key Technologies

  • Suitable lasers

  • Telescope tracking and guiding

  • Optical detectors

  • Cost-effective large-aperture telescopes

  • Atmospheric properties

  • Space-borne telescopes



NASA approach today

  • Pursuing two approaches



Optical spacecraft comms

  • ESA have already run intersatellite test

  • NASA/JPL and Japan presently researching the concept and expect space-ground communications tests in the near future



NASA optical comms plans

  • Operational demonstration on Mars Telecom Orbiter (2009)

    • 5W average power (300W peak)
    • 1064μm wavelength (NIR)
    • 300mm aperture transmitter
    • 3 – 10 Mbps
    • 3-9 х 8-10m receiving telescopes


AAO input

  • Proposed NASA parameters near-identical to AAO suggestions

  • AAO discussions with NASA to encourage change in wavelength (to 532nm)

  • Go for Green!



AAO input – 532 vs. 1064nm

  • Achieve change with frequency doubler cell (can conceivably switch in & out)

  • Better pointing (so higher power density, less spill) 

  • Worse detector efficiency 

  • Visible (marginally by eye, certainly by amateur astronomers) – public relations coup comparable to USSR Sputnik

  • Suggestion favourably received by NASA and under serious consideration



An Australian Role

  • Australian organisations have unique capabilities in the key technologies required for deep space optical communications links

      • Existing DSN involvement
      • High-power, high beam quality lasers
      • Holographic correction of large telescopes
      • Telescope-based instrumentation
      • Telescope tracking and guiding


Australian involvement in missions to Mars

  • Take advantage of unique Australian capabilities

  • Australian technology critical to deep space missions

  • Continued important role in space





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