Astronomers Returns to the Stratosphere


Published on

Description of NASA's Stratospheric Observatory for Infrared Astronomy.

Published in: Technology
  • Be the first to comment

  • Be the first to like this

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide
  • With all that being said – I would like to review the progress of the SOFIA development program that has been a long time in the offing.
    SOFIA – which stands for S_O_F_I_A is a partnership between NASA and the DLR (the german space agency). With NASA providing the aircraft and the base of operations (NASA Ames) and the DLR providing the telescope and an 80:20 split in the cost of operations – the observatory is expected to achieve approximately 960 successful science hours per year (with U.S. and German telescope time in the same 80:20 split).
    This photo shows the pre-modified aircraft during flight testing with the United colors as purchased by NASA in 1997. The blacked section show where to the SOFIA telescope and cavity door will be located. The aircraft was actually christened the ‘clipper lindbergh’ on the 50th aniversary of Lindbergh’s flight while part of the Pan Am flight by Anne Morrow Lindbergh. The SP designation is because the aircraft is somewhat shorter then the -100 design and was developed for Pan Am for non-stop flights between New York and Tokyo.
  • This is a listing of the attributes of SOFIA under a variety of catagories. Compaired to the KAO, the big difference is in the size of the telescope aperture. Overall, the two facilities offer unique advantages of a sub-orbital program with the added benefit of frequent flight opportunities and a extremely high probability of getting successfully getting down from 41, 000 feet (to fly another day).
    I should also note, that like the KAO, SOFIA will observe in both the northern and southern hemisphere. With a northern hemisphere base of operations at NASA Ames, the southern hemisphere base is typically Auckland or Christ Church New Zealand. As an FAA certified aircraft, operations can be most any where the 747’s currently operate.
    There are additional details about the aircraft that I don’t plan to discuss today. If you have any questions, you can save them for later or see me during this week’s meeting.
  • The differences between the KAO and SOFIA are best demonstrated through this figure of the Orion reqion. The KAO (which had an image quality comparable to Spitzer – 91 cm vs. 85 cm telescope) provided this 60 image of Orion which is shown next to a Hubble image of the same region. I have noted for SOFIA, the decrease in beam size associated with the larger 2.5-meter aperture of the SOFIA telescope. What we can expect to see with SOFIA (and Herschel for that fact) will be near optical quality images in the far-infrared. As an astronomer who has had to deal mostly with blobbed out contour maps, I find this prospect to be very, very exciting. Within these enegetic regions, we have the ability to discern details that have otherwise been hidden by the limitations of our facilities. I have another image taken with proto-type detectors on the CSO that demonstrate this capability very nicely.
  • This figure shows the interior of the SOFIA aircraft. The telescope is contained within an open port cavity and is isolated from the aircraft cabin by a single pressure bulk head. Many years of wind tunnel studies at NASA Ames have led to the development of ‘partial exterior’ cavity door design that was developed to minimize the turbulence within the telescope cavity. There are no outstanding technical issues with this design (as you can read about in the letter from Nans Kunz, the SOFIA chief engineer to the NASA chief engineer on the NASAwatch web page. The layout of personal accommodations includes space for the instrument team, operations staff, pilots, and an education and public outreach participation. The cavity cooling system is shown in the rear and is required for pre-cooling the telescope prior to each mission and for drying the cavity air during decents from the stratosphere. The telescope cavity is maintained as a class 1000 clean room to eliminate the risk of telescope optics contamination while at sea level.
  • This slide shows the optical configuration of the telescope. The pressure bulk head is show that isolates the cabin and cavity environments. A drichroic beam splitter separates the infrared and optical light. Optical light is directed to a focal plane guider that assists with actual telescope pointing. The science instruments mount to a counter weight rack, that you will see later, and is located at the infrared focus of the telescope. The secondary mirror is actually a chopping secondary that allows for the two-beam, many-beam, chopping and nodding. The telescope also has the ability to do continuous spans along the +/- 3 degree range of motion of the hydraulic spherical bearing. As I will show, this German built telescope has been installed and operated and is a fantastic bit of engineering.
  • This is the telescope’s light-weighted zerodur primary mirror. It is actually 2.7-meters in diameter to allow for a properly undersized chopping secondary mirrior diameter. The mirror is light-weighted with machining through the mirrors back surface. It will be aluminized at NASA Ames following successful test flights of the observatory system. As a glass blank, it does provide a reflective surface of a few percent which was enough for initial ‘first light’ ground based testing in Waco, Texas.
  • Following the development and testing of the telescope sub-assembly in Germany, the complete system was shipped aboard an Airbus Super Guppy to Waco, Texas (the home L3 communications – our partners in this program and the lead for the SOFIA aircraft modifications). A crane is shown pulling off the telescope truss structure, the telescope sphereical bearing and hydrolics, and the telescope’s primary mirror.
  • Here is a shot of the Primary mirror going in after the installation of the telescope bearing and truss structure. You can see the modified aircraft fuselage (everything that is green is new to the aircraft) and the pressure bulk head. The mirror (which you can see) is supported by it’s own truss structure and is supported by a series of hexipods that are actually glued to the back surface of the primary mirror. The dates for these photo graphs is shown in the upper left-hand corner.
  • Here is a shot through the cavity opening of the completely assemblied telescope. The truss (which is a composite material) is still covered by it’s protective shrink wrap. The primary mirror surface is protected by a red cover. The secondary mirror mount is in position. This photo does not show the tertiary mirror (which was installed at a later date). The pressure bulk head is shown.
  • Some six months later, with the telescope installation complete, the aircraft under went a successful pressure test of the fuselage. The test is to develop a pressure differential similar to what is experienced by the aircraft at altitude. Cabin altitudes are typically 8,000 feet. The netting is in base a panel blows during the test. (You can find some very exciting photos of aircraft failing their pressure tests on the net – Ed Erickson has one. These are not very pretty when they result in a catastrophic mechanical failure). The quality of the SOFIA aircraft modification was demonstrated by the successful completion of this very important airworthiness test.
  • Here is another photograph of the airplane during the test of the landing gear (as required for all first flight testing). The engines are mounted although I don’t know if these are the orginal A-engines that United provided or if these are the J-engines that the Deustches SOFIA Instutitue (DSI) just provided. The landing gear did retract without a problem. Another successful sub-system test for the facility.
  • The competed aircraft cavity door is shown here. It looks very similar to the solid models shown previously. The door consists of an upper rigid segment and a lower flexible door segment. The upper door closes over the telescope aperture to seal off the cavity while on the ground and prior to reaching attitude. Both segments track with the telescope through the range of elevations typical of SOFIA (20 – 60 degrees). This elevation range means that you very detailed flight plans before each flight so you fly in the right direction to observe the targets that you desire. The aft ramp is positioned to re-connect the aircraft’s boundary layer to the fuselage and avoid the right angle portion of the aft cavity door modification. Given all the wind tunnel tests that have been done, we are pretty much in the position of having to fly the ‘one-inch equals one-inch” model of this facility in order to verify the final the final design. Everyone is anxiously awaiting these test flight results and the resultant forcing function within the telescope cavity.
  • Not only does this apply to the galactic center, as it does to star forming regions. Debris disks are a very popular topic. In the decades ahead, infrared observations are likely to provide the data needed to formulate a complete classification of planetary formation in a fashion similar to the development of MK stellar classification during the 30’s and 40’s. My expectation, however, is that our understanding of planetary formation will development much quicker then the theory of stellar interiors (following stellar classification).
    Again, the diagnostics of these regions – line and continuum emission – will come from observations throughout the infrared. This includes the emission of material during both the earliest and latest stages of planetary formation.
    The images below are continuum images in the submm of several popular debris disks. With the KAO, the 100 micron beam size was typically 45” (or so). At submm wavelengths, the beam sizes are as shown. Note that aboard SOFIA, the far-infrared beam size is comparable.
    Infrared observations – and the instrument to perform these observations – are essential if we are to understand the planetary formation process. With missions such as Spitzer and Herschel, we will be developing a growing catalog of these sources. Follow-up observations, beyond what these missions are able to achieve will be required if we are to understand the energetics, kinematics, and chemistry of these regions.
  • Star formation, dynamics and chemical content of other galaxies:
    How different are the interstellar media of other galaxies?
    Why do some exhibit extraordinary large infrared luminosities?
    What triggers a galaxy-wide starburst?
    How do interstellar media of galaxies evolve?
    What are the large scale effects of galactic environments on star formation rates and IMF?
    Interstellar cloud chemistry and dynamics, and star and planet formation in our galaxy:
    How does the interstellar medium chemically evolve?
    What is the nature of collapse, accretion, and outflow processes in star formation, and how are they related?
    How do disks form and what evidence is there for planet formation?
    The dynamic activity in the center of our own galaxy:
    What’s happening now, what will happen next?
    Origin and evolution of biogenic materials in the interstellar medium and in proto-planetary disks:
    What environments are hospitable to pre-biotic molecules and compounds?
    Comets, planet atmospheres and rings in our solar system:
    How did our solar system evolve?
    What was the initial composition of the solar nebula?
  • Astronomers Returns to the Stratosphere

    1. 1. Presenter: Name 1 NASA ARC - AIAA September 14, 2010 Moffett Field, CA Presented By Sean C Casey Universities Space Research Association Stratospheric Observatory for Infrared Astronomy (SOFIA)
    2. 2. Presenter: Sean C. Casey 2 Talk Outline • Introduction on Airborne Astronomy • Construction of the observatory • SOFIA’s expected science return • Summary
    3. 3. Presenter: Sean C. Casey 3 Astronomy in the Infrared • Astronomical observatories throughout the EM spectrum • Wavelength is indicative of the energetics Optical
    4. 4. Presenter: Sean C. Casey 4 Friedrich Wilhelm Herschel 1738 - 1822 The 18th Century Discovery of Infrared Radiation (IR) Discovered the planet Uranus!
    5. 5. Presenter: Sean C. Casey 5 21st Century Imaging in the Optical and Infrared Optical (What your eye does see.) Infrared (What your eye does not see.) A Collard Lizard
    6. 6. Presenter: Sean C. Casey 6 Astronomy in the Optical and Infrared Cooled gas and dust emission at T = 10’s – 100’s K
    7. 7. Presenter: Sean C. Casey 7 Interstellar Dust Carbonaceous and Silicate condensates of the ISM. Particle size produces selective extinction (σs+σa).
    8. 8. Presenter: Sean C. Casey 8 Looking toward the center of our Galaxy Optical Image Near-Infrared Far-Infrared • Imaging at longer wavelengths – Optical shows only cloud surfaces – Infrared provides diagnostics of obscured environments
    9. 9. Presenter: Sean C. Casey 9 Lifecycle of the ISM X. Tielens 2006
    10. 10. Presenter: Sean C. Casey 10 Atmospheric Absorption 0.0 0.2 0.4 0.6 0.8 1.0 145 150 155 160 165 C+ R ~ 10,000 Observations within the 30 – 300 micron window are only possible from the stratosphere and above.
    11. 11. Presenter: Sean C. Casey 11 Previous and Existing IR Observatories Ground-based Sub-orbital IRAS COBE ISO SIRTF Space-based KAO Mauna Kea
    12. 12. Presenter: Sean C. Casey 12 Kuiper Airborne Observatory : 1974 - 1995 >300 investigators, ~50 PhDs, ~40 instruments, ~9000 observing hours Important Science results: - Life cycle of gas and dust in the ISM - Recognition of photo-dissociation regions - Numerous far-IR lines OI, CII, FeIV - PAH emission characteristics - Far-Infrared polarization - Ring of Uranus Set the scientific stage for the infrared missions: IRAS, ISO, and Spitzer
    13. 13. Presenter: Sean C. Casey 13 Typical instrumentation aboard KAO Pre-flight checkout of FIFI on the KAO by A. Poglitsch and Team (Genzel et al.). Successful development and use of stressed/ unstressed germanium photo-conductors in far-IR. Successful International participation
    14. 14. Presenter: Sean C. Casey 14 Astronomy aboard an Airplane A. Krabbe and H-P. Roeser 1999 “SOFIA Astronomy and Technology in the 21st Century”
    15. 15. Presenter: Sean C. Casey 15 Flight Profiles – Start at 37,000 Feet • Some research flights may reach duration of 10.5 Science Hours START, TAXI, TAKEOFF GW 648.0 CRUISE 108,000 LBS. FUEL F.F. 22,520 LBS/HR 4.6 HRS. 37,000 FT. GW 628.0 CRUISE 40,000 LBS. FUEL F.F. 19,480 LBS/HR. 1.9 HRS. CRUISE 40,000 LBS FUEL F.F. 18,380 LBS/HR. 2.05 HRS. CRUISE 35,000 LBS. FUEL F.F. 16,920 LBS/HR. 2.05 HRS. TOTAL FUEL USED – 268,000 LBS. TOTAL CRUISE TIME – 10.6 HRS. TOTAL FLIGHT TIME – 11.9 HRS. ASSUMPTIONS ZFW 380,000 LBS. 20,000 LBS. FUEL TO FIRST LEVEL OFF CLIMB TO FIRST LEVEL-OFF AT MAX CRUISE WT STAY AT ALT. UNTIL FUEL FLOW IS LESS AT STEP CLIMB ALT .1 HRS.FOR EACH STEP CLIMB LANDING WITH 20,000 LBS. FUEL BASED ON 747 SP FLIGHT MANUAL TABULATED DATA STANDARD DAY PLUS 10 DEGREES C SPEED-MACH .84 39,000 FT. GW 520.0 41,000 FT. GW 480.0 43,000 FT. GW 440.0 DESCENT GW 405.0 5,000 LBS. FUEL .5 HRS. LANDING GW 400.0 CLIMB .5 HRS.
    16. 16. Presenter: Sean C. Casey 16 Stratospheric Observatory For Infrared Astronomy 747-SP “Clipper Lindbergh” Aircraft flight tests, circa 1997/8
    17. 17. Presenter: Sean C. Casey 17 SOFIA Attributes - Wavelength range: “UV to Radio”: 0.3 – 1600 µm - Mobility: “anywhere, any time”: all sky, ephemeral events - Primary Mirror: 2.7 m diameter (Aperture 2.5 m) - Operating Altitude: 12 – 14 km (37,000 - 45,000 feet) - Design Lifetime: 20 years - Observing Program: flexible; annual proposal opportunities - Science Instruments: wide variety, hands-on in-flight, late latest technologies in new instruments - Young researchers’ opportunities: scientists and instrumentalists - Education/Public Outreach: teachers/media/public SOFIA will be a mobile modern observatory in the lower stratosphere.
    18. 18. Presenter: Sean C. Casey 18 Angular resolution of SOFIA HST in optical KAO at 60 µm SOFIA: KAO Comparison - almost 9 SOFIA beams for every 1 KAO beam Orion in Optical and Far-infrared
    19. 19. Presenter: Sean C. Casey 19 Education & Public Outreach Section Mission Control & Science Operation Section Pressure Bulkhead Telescope Cavity Door Science Instrument Cavity Environmental Control System Telescope 2.7m SOFIA’s Interior Layout Open Port Cavity
    20. 20. Presenter: Sean C. Casey 20 SOFIA’s Optical Layout
    21. 21. Presenter: Sean C. Casey 21 Photometric Sensitivity and Angular resolution SOFIA is diffraction limited beyond 25 µm (θmin ~ λ/10 in arcseconds) and can produce images three times sharper than those made by Spitzer SOFIA is as sensitive as ISO
    22. 22. Presenter: Sean C. Casey 22 SOFIA’s Operational Phase Space
    23. 23. Presenter: Sean C. Casey 23 10 0 10 1 10 2 103 10 4 10 5 10 6 107 10 8 1 10 100 1000 Wavelength [µm] Spectralresolution HIPO FLITECAM FORCAST EXES HAWC SAFIRE FIFI LS GREAT CASIMIR Planetary AtmospheresPlanetary Atmospheres Planetary AtmospheresPlanetary Atmospheres Chemistry of the cold ISMChemistry of the cold ISM Comet MoleculesComet Molecules Dynamics of the Galactic CenterDynamics of the Galactic Center Dynamics of collapsing protostarsDynamics of collapsing protostars Velocity structure and gas composition inVelocity structure and gas composition in disks and outflows of YSOsdisks and outflows of YSOs Composition/dynamics/physics of theComposition/dynamics/physics of the ISM in external galaxiesISM in external galaxiesPAH & organic moleculesPAH & organic molecules Nuclear synthesis in supernovae in nearby galaxiesNuclear synthesis in supernovae in nearby galaxies Composition of interstellar grainsComposition of interstellar grains KBOs, Planet TransitsKBOs, Planet Transits Debris Disk StructureDebris Disk Structure Luminosity and Morphology of Star Formation GalacticLuminosity and Morphology of Star Formation Galactic and Extra-Galactic Regionsand Extra-Galactic Regions SOFIA Science is broadly based
    24. 24. Presenter: Sean C. Casey 24 Current Instruments Early Science SIs
    25. 25. Presenter: Sean C. Casey 25 SOFIA Instruments #1 #2 Working/complete HIPO instrument at Lowell Obs. Aug 2004 Working/complet e FLITECAM instrument at Lick in 2004/5 Working FORCAST instrument at Palomar in 2005 Successful lab demonstration of GREAT in Oct 2005 HAWC flight cryostat testing at Yerkes in 2005 Early science instruments: FORCAST/GREAT
    26. 26. Presenter: Sean C. Casey 26 FORCAST: Mid-IR Imager PI: T. Herter (Cornell Univ.) Detectors: Dual channel 256 x 256 arrays; 5 – 25 µm (Si:As) 20 – 40 µm (Si:Sb) Field of View: 3.2’ x 3.2’ Science: Thermal and narrow band imaging Targets: Circumstellar disks, Galactic Center, Galactic and extragalactic star formation NB: Diffraction Limited > 15 microns; Grism upgrade funded (Ennico 2005) Working FORCAST instrument at Palomar in 2006
    27. 27. Presenter: Sean C. Casey 27 GREAT: Heterodyne Spectrometer PI: R. Guesten, Max-Planck Institut, Bonn R= 106 -> 108 Detector: dual channel mixer (HEB); 60 – 200 µm (2 – 5 THz) Science: Spectroscopy of CII (158 µm), and HD (112 µm) Targets: Galactic and extragalactic ISM, circumstellar shells Successful lab demonstration of GREAT in Oct 2005 NB: TA ~ 2500 K at 158 µm High frequency upgrade at 4.7 THz expected for OI (63 µm). Field of View: single element
    28. 28. Presenter: Sean C. Casey 28 SOFIA Aircraft: 747 SP #21441 as proposed by USRA Christened the “Clipper Lindbergh” by Anne Morrow Lindbergh in May 1977 on the 50th anniversary of Lindbergh’s flight across the Atlantic. Juan Trippe and Charles Lindbergh with Pan Am in mid-1930’s. Summer ‘97 Observatory Hardware
    29. 29. Presenter: Sean C. Casey 29 2.7 M Primary Mirror, f/1.28 at SAGEM, circa 2000 RMS = 280 nm
    30. 30. Presenter: Sean C. Casey 30 Aircraft pressure bulk head ’01 (assembly) ’02 (installation)
    31. 31. Presenter: Sean C. Casey 31 Build-up of the DLR telescope components in Germany. Complete telescope assembly (TA) run with closed-loop servo control using the hydrostatic bearing and gyroscopic control. Telescope metering structure Science Instrument end of TA March ‘02
    32. 32. Presenter: Sean C. Casey 32 Telescope arrives in Waco, TX Sept. ‘02
    33. 33. Presenter: Sean C. Casey 33 July ’03 – primary mirror installed
    34. 34. Presenter: Sean C. Casey 34 August ’03 – Telescope installation complete
    35. 35. Presenter: Sean C. Casey 35 March ’04 – Proof pressure test SOFIA passes test!
    36. 36. Presenter: Sean C. Casey 36 February ‘05 – Test of landing gear
    37. 37. Presenter: Sean C. Casey 37 February ‘06 – Aircraft aperture door complete
    38. 38. Presenter: Sean C. Casey 38 SOFIA Instrument Flange
    39. 39. Presenter: Sean C. Casey 39 SOFIA’s Interior Aircraft interior Sept. 06
    40. 40. Presenter: Sean C. Casey 40 SOFIA with NASA colors
    41. 41. Presenter: Sean C. Casey 41 SOFIA is Airborne in 2007
    42. 42. Presenter: Sean C. Casey 42 SOFIA at ARC in 2007
    43. 43. Presenter: Sean C. Casey 43 SOFIA at NASA Dryden
    44. 44. Presenter: Sean C. Casey 44 Uncoated Telescope/Incomplete Door
    45. 45. Presenter: Sean C. Casey 45 Finishing the Door
    46. 46. Presenter: Sean C. Casey 46 A coated primary mirror
    47. 47. Presenter: Sean C. Casey 47 Optical telescope tests with HIPO team
    48. 48. Presenter: Sean C. Casey 48 SOFIA Line-Op
    49. 49. Presenter: Sean C. Casey 49 Telescope Testing
    50. 50. Presenter: Sean C. Casey 50 Telescope Close-up
    51. 51. Presenter: Sean C. Casey 51 Telescope for Test Flights
    52. 52. Presenter: Sean C. Casey 52 FORCAST on SOFIA
    53. 53. Presenter: Sean C. Casey 53 SOFIA First Light - Jupiter
    54. 54. Presenter: Sean C. Casey 54 Will SOFIA reveal debris disks @ 37 µm? Wilner et al. model of Vega predicts resolved structure when convolved with SOFIA resolution @ λ=37 µm (LEFT), but Spitzer finds Fomalhaut (RIGHT) and Vega (not shown) amorphous at λ=24 µm. Due to small grains or small inner disk radius?? - ask SOFIA! ? Vega model SOFIA @37 µm Fomalhaut Spitzer MIPS @24 µm 72 FORCAST beam size at 37 µm
    55. 55. Presenter: Sean C. Casey 55 Malfait et al. 1998 Debris Disk Evolution VegaFomalhaut Beta Pic
    56. 56. Presenter: Sean C. Casey 56 Segregation of gas & ices around protostars van Dishoeck & Hogerheijde 1999 W33A Gibb et al. 2000 R~2000 FLITECAM and FORCAST (with grisms) observations can reveal constituents & chemistry of protostellar envelopes (except for CO2).
    57. 57. Presenter: Sean C. Casey 57 Occultation astronomy with SOFIA Pluto occultation lightcurve observed on the KAO (1984) probes the atmosphere •SOFIA can fly anywhere on the Earth, allowing it to position itself under the shadow of an occulting object •Occultation studies with SOFIA will probe the sizes, atmospheres, and possible satellites of Kuiper belt objects and newly discovered planet-like objects in the outer Solar system. The unique mobility of SOFIA opens up some hundred events per year for study compared to a handful for a fixed observatory. •SOFIA’s mobility also enables study of comets, supernovae and other serendipitous objects SOFIA will measure stellar occultations
    58. 58. Presenter: Sean C. Casey 58 Transits of Extrasolar Planets • SOFIA will fly above the scintillating components of the atmosphere and will be the most sensitive freely pointing observatory for extrasolar planetary transits after HST. • SOFIA will be able to detect weak transit signals with high signal-to-noise, conclusively determining the status of candidate extrasolar planets discovered by transit surveys: long life needed! HD 209458 artist’s concept (left) and HST STIS data (below)
    59. 59. Presenter: Sean C. Casey 59 The ground-based infrared spectrum of Mars is dominated by broad lines in the Earth atmosphere. A weak feature on the wing of the strong terrestrial methane line may be the Doppler-shifted methane line in the Mars atmosphere. If true, the methane abundance is very high and may reflect biogenic activity. The high resolution spectrograph on SOFIA can probe between the much narrower terrestrial lines at airborne altitudes and uniquely address: • Is there methane in the Martian atmosphere? • If so, where does it come from? What is it global distribution? How does it vary with the seasons on Mars? SOFIA will study planetary atmospheres Planetary Atmospheres
    60. 60. Presenter: Sean C. Casey 60 Phillips 1988 Astrochemistry • Most molecular lines in IR or submillimeter – Need high spectral resolution throughout the submillimeter • As sensitive as CSO, but complete wavelength range is accessible – H2, C2H2,CH4 only in IR • The fullerene, C60, has 4 IR lines in SOFIA’s bands • Light molecules: Hydrogen, water, other hydrides in IR and submillimeter • HD at 112 microns
    61. 61. Presenter: Sean C. Casey 61 Evolution of the Universe Atmospheric transmission around the HD line at 40,000 feet Only the high resolution spectrograph on SOFIA can measure the deuterium abundance throughout our galaxy and answer: • What is the abundance of deuterium and how does it vary with the local star formation rate in galaxies? • What does that tell us about the Big Bang and about the star formation history of galaxies? Deuterium in the universe is created in the Big Bang and the primordial deuterium abundance provides the best constraints on the mass density of baryons in the universe. However, this Big Bang record is subsequently modified by stellar nuclear burning as material cycles from stars to the interstellar medium and back to stars. SOFIA will study the deuterium abundance in the galaxy, investigating the evolution of the universe
    62. 62. Presenter: Sean C. Casey 62 SOFIA’s Next Steps • Short Science Flights – FORCAST – Oct 2010 (3 flights) – GREAT – Feb 2010 (3 flights) • Basic Science Program (50+ proposals) – Shared risk flights with FORCAST & GREAT – Summer 2011 (20 flights) • Completion of observatory updated – 2011 – 2012 (down time) • Full Operating Capabilities – 2013 & beyond (working to 100+ flights/year)
    63. 63. Presenter: Sean C. Casey 63 Science and Instruments • SOFIA offers unique capabilities within NASA – Serving two communities • Instrument developers – offers a robust instrument program • General Investigators – access to latest technologies – Capable sub-orbital platform • Daily, weekly, monthly, yearly access to observatory • Ready access to science instruments • Track record for new technologies • Science instrument development is an essential element of successful SOFIA operations.
    64. 64. Presenter: Sean C. Casey 64 Summary of SOFIA Goals • Science: Provide high angular and spectral resolution imaging through-out the infrared and sub-millimeter. • Technology: Provide a well calibrated and understood platform for state-of- the-art infrared and sub-millimeter instrumentation. • Education: Provide readily accessible educational and public forums which encourage the study of astronomy.
    65. 65. Presenter: Sean C. Casey 65 Additional Material
    66. 66. Presenter: Sean C. Casey 66 1988 Kuiper Airborne Obs. 6 x 6 Bolometer Camera 1994 South Pole 128 x 128 Si:Sb BIB Spectrometer 1997 Apache Point Obs. 1024 x 1024 InSb Camera Historical photos
    67. 67. Presenter: Sean C. Casey 67 Organic Growth & Chemistry in the ISM Formation Processing Fossil / Delivery
    68. 68. Presenter: Sean C. Casey 68
    69. 69. Presenter: Sean C. Casey 69 Telescope for Astronomy
    70. 70. Presenter: Sean C. Casey 70 SOFIA First Light – M82
    71. 71. Presenter: Sean C. Casey 71 SOFIA Science is broadly based • Star formation, dynamics and chemical content of other galaxies: • Interstellar cloud chemistry and dynamics, and star and planet formation in our galaxy: • The dynamic activity in the center of our own galaxy: • Origin and evolution of biogenic materials in the interstellar medium and in proto-planetary disks: • Comets, planet atmospheres and rings in our solar system:
    72. 72. Presenter: Sean C. Casey 72 GREAT: Heterodyne Spectrometer PI: R. Guesten, Max-Planck Institut, Bonn R= 106 -> 108 Detector: dual channel mixer (HEB); 60 – 200 µm (1.4 - 5THz) 60 - 300 µm Science: Spectroscopy of CII (158 µm), and HD (112 µm) Targets: Galactic and extragalactic ISM, circumstellar shells Successful lab demonstration at 1.9 THz of GREAT in July 2005 NB: TA < 2500 K at 158 µm High frequency upgrade at 4.7 THz expected for OI (63 µm). Field of View: single element
    73. 73. Presenter: Sean C. Casey 73 Science Capabilities • Sensitivity – Telescope Emissivity ~ 0.1 Temperature ~ 240 K – 40 to 300 µm • ~ ISO point source (both imaging and spectroscopy) – 5 to 40 µm • ~ 8 meter ground-based telescope at 20µm • FOV 8 arcmin diameter • Image Size – > 15 µm: diffraction limited: 3 times better than Spitzer θ(FWHM) ~ λ(µm) / 10”
    74. 74. Presenter: Sean C. Casey 74 SOFIA, Herschel, and JWST 2008-2012 2014-2019
    75. 75. Presenter: Sean C. Casey 75 HIPO: High Speed Imager PI: T. Dunham (Lowell Observatory) Detector: Dual channel 1Kx1K CCDs Field of View: 5.6’ x 5.6’ #1 #2 Working/complete HIPO instrument at Lowell Obs. Aug 2004 Science: Occultations Targets: Pluto, Triton, KBOs. NB: Co-mounts w. FLITECAM
    76. 76. Presenter: Sean C. Casey 76 August ’04 – Optical telescope tests with HIPO team
    77. 77. Presenter: Sean C. Casey 77 NASA technology readiness level (TRL) • Technology readiness defined – NASA/DOD – 9 levels • Technology migration is an issue – Science enabling technologies are essential to future NASA missions – Diminishing funds at the lowest and highest levels create the “mid-TRL desert” • Mitigation of new technology risks – Missions invest in critical technologies • Spitzer - IRAC bridge chips • JWST - micro shutters arrays • Herschel - mixers/local oscillators – System level integration is an issue • Converting photons into published results
    78. 78. Presenter: Sean C. Casey 78 SOFIA Instrument Definitions • Principal Investigator Science Instruments (PSI) – Cutting edge technologies (low-TRL) – Developed and operated by PI teams – General investigators work with PI teams • Facility Science Instrument (FSI) – Mature technologies (mid-TRL) when possible – Developed and delivered by PI teams – General investigators work with Observatory staff • SOFIA must balance PSI and FSI programs – New SI, existing SI upgrades, & focused technology development
    79. 79. Presenter: Sean C. Casey 79 HIPO: High Speed Imager PI: T. Dunham (Lowell Observatory) Detector: Dual channel 1Kx1K CCDs Field of View: 5.6’ x 5.6’ #1 #2 Working/complete HIPO instrument at Lowell Obs. Aug 2004 Pluto occultation from KAO (Elliot, et al. 1989) Science: Occultations Targets: Pluto, Triton, KBOs. NB: Co-mounts w. FLITECAM
    80. 80. Presenter: Sean C. Casey 80 FLITECAM: Near-IR Imager PI: I. McLean (UCLA) Detector: Single 1K x 1K array; 1-5 µm (InSb) Field of View: 8.2’ x 8.2’ Science: Imaging, Spectroscopy, Occultations Targets: Galactic, extragalactic Grism observations from Lick of NGC 7027 NB: SOFIA seeing limits (129.01) Working/complet e FLITECAM instrument at Lick in 2004/5 R ~ 2000