SOFIA PROGRAM OVERVIEW and SCIENCE PROMISE

1. SOFIA PROGRAM OVERVIEWand SCIENCE PROMISE E.E. Becklin SOFIA Chief Scientist

2. Outline of Material • Overview of SOFIA • Science • Instrumentation • Compatibility with other Observatories • Operations Plans • Summary and Perspective • SOFIA is a World Class Observatory that will make unique far-infrared observations that are impossible from the ground or US space observatories

3. Overview

4. Overview of SOFIA • SOFIA is 2.5 m telescope in a modified B747-SP aircraft • Optical-mm performance • Obscured IR (30-300 m) most important • Operating altitude • 39,000 to 45,000 feet (12 to 14 km) • Above > 99% of obscuring Water Vapor (>80% Average Transmission) • Joint Program between the US (80%) and Germany (20%) • Science Operations (NASA, DLR, USRA, DSI) • Designed for 20 year lifetime • Operations Center ~80-people, 20% German • Deployments • >120 flights per year of 8 to 10 Hours • Build on KAO Heritage, with Significant Enhancements (FSI’s, Science Support)

5. Why SOFIA? • Atmosphere: above 99% of the water vapor • IR transmission at 14 km very good: >80% from 1 to 800 mm • Instrumentation: wide complement, rapidly interchangeable, state-of-the art • Mobility: anywhere, anytime • Long lifetime • A near-space observatory that comes home after every flight

6. SOFIA’s Instrument Complement • As an airborne mission, SOFIA has a unique, wide instrument complement • SOFIA covers the full IR range with imagers and low, moderate, and high resolution spectrographs • 4-5 instruments at Initial Operational Capability (IOC); 8-9 instruments at Full Operational Capability (FOC) • SOFIA can take full advantage of improvements in instrument technology • Both Facility and PI Instruments

7. Science

8. Science Capabilities • Because of large aperture and better detectors, sensitivity for imaging and spectroscopy similar to the space observatory ISO • 8x8 arcmin FOV allows use of very large detector arrays • Image Size is diffraction limited making it 3 times sharper than space observatory Spitzer

9. Star and Planet Formation SOFIA will study the molecular composition of regions of star and planet formation Spectroscopy reveals the presence of water, simple hydrocarbon molecules, and complex nitrogen-bearing organics in regions of star formation • SOFIA’s high resolution spectrographs are unique for precisely identifying organic and pre-biotic molecules, determining their abundances, and identifying chemical routes and thus to uniquely address: • What is the organic inventory of newly forming planetary systems? • What is the distribution of water, where is the “snow-line” in newly forming planetary systems? NASA strategic sub-goal 3D.3

10. Debris Disks SOFIA will study debris disks Infrared continuum studies have revealed that dusty protoplanetary disks are common around many young main sequence stars. However, the gas content of such disks is much more difficult to probe. • The high resolution spectrograph on SOFIA is uniquely sensitive for probing the abundance, kinematics, and evolution of the most abundant molecule, molecular hydrogen and thus addressing: • Is there only dust or also gas? • The dust content evolves with time. Does the gas content evolve with time as well? Do gas and dust vary in lock step? • What are the dynamics of these disks? NASA strategic sub-goal 3D

11. Occultation astronomy with SOFIA SOFIA will study stellar occultations Pluto occultation lightcurve observed on the KAO (1989) 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

12. Planetary Atmospheres SOFIA will study planetary atmospheres 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? NASA strategic sub-goal 3C.2

13. SOFIA will fly above the scintillating component of the atmosphere and will provide the most sensitive freely pointing observatory for extrasolar planetary transits after HST SOFIA’s HIPO and FLITECAM instruments can observe with high signal-to-noise the small variations in stellar flux due to a planet transit and Provide good estimates for the mass, size and density of the planet May reveal the presence of star spots, satellites, and/or planetary rings Extrasolar Planet Transits SOFIA will observe extrasolar planet transits Artist concept of planetary transit and the lightcurve of HD 209458b measured by HST revealing the transit signature

14. Feeding the Black Hole in the Center of the Galaxy • One of the major discoveries of the KAO was a ring of dust and gas orbiting the very center of the Galaxy • The ring of dust and gas will fall into the black hole • SOFIA’s angular resolution and spectrometers will tell us: • How much matter gets fed into the black hole? • How much energy is released? • What is the relationship to high energy active galactic nuclei? • Astronomers at ESO and Keck detected fast moving stars revealing a 4 x 106 solar mass black hole at the Galactic Center

15. Resolving Star Formation: Spitzer & SOFIA NASA/JPL-Caltech/V. Gorjian NASA/JPL-Caltech/Z. Wang Henize 206- LMC high mass star formation MIPS @ 24 mm (80s, 20’ x 20’) HAWC @ 53 / 89 mm? (mosaic) Antennae Galaxies IRAC @ 8 mm (red; 160s, 4’ x 4’) FORCAST @ 24 mm

16. FIFI-LS Observations of Nearby Galaxies

17. Evolution of the Universe SOFIA will study the deuterium abundance in the galaxy, investigating the evolution of the universe Atmospheric transmission around the HD line at 40,000 feet 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. • 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? NASA strategic sub-goal 3D.1 and 3D.2

18. 8 10 7 10 Planetary Atmospheres Chemistry of the cold ISM 6 Dynamics of collapsing protostars 10 Comet Molecules Dynamics of the Galactic Center 5 10 Velocity structure and gas composition in disks and outflows of YSOs 4 Composition/dynamics/physics of the ISM in external galaxies 10 Spectral resolution PAH & organic molecules 3 10 Nuclear synthesis in supernovae in nearby galaxies Composition of interstellar grains 2 10 Debris Disk Structure KBOs, Planet Transits Luminosity and Morphology of Star Formation Galactic and Extra-Galactic Regions 1 10 0 10 1 10 100 1000 Wavelength [µm] SOFIA: Science For the Whole Community

19. Science Summary • The science vision for SOFIA is: • Studying the origin of stars and planetary systems • Studying the planetary bodies that make up our Solar System • Studying the life-cyle of dust and gas in galaxies • Studying the composition of the molecular universe • Studying the role of star formation and black hole activity in the energetics of luminous galaxies • SOFIA has a unique suite of instruments that cover a wide range of wavelengths at a wide range of spectral resolution. Most have upgraded their detectors and science. • SOFIA will be continuously and inexpensively upgraded with new instrumentation and will serve as an important technology development platform for future space missions and will allow new and important science, such a full mapping of molecular hydrogen and unique magnetic field studies. • SOFIA is a highly visible icon for education and public outreach and will immerse educators in the scientific process.

20. Instrumentation

21. SOFIA’s First Generation Instruments • Both German and US • Four are ready now!

22. Four First Light Instruments Working/complete HIPO instrument in Waco on SOFIA during Aug 2004 Working/complete FLITECAM instrument at Lick in 2004/5 Working FORCAST instrument at Palomar in 2005 Successful lab demonstration of GREAT in July 2005

23. Compatibility of SOFIA with Other Observatories

24. IR Missions Mission operations timeline SOFIA has a unique wide instrument set which complements the wavelength ranges and spectral capabilities of NASA space missions over the designed 20 year lifetime

25. SOFIA and Spitzer • Spitzer is a high sensitivity imaging and low resolution spectroscopy mission. • SOFIA is a high spectral and high angular resolution mission. • When Spitzer runs out of cryogens in early FY’09, SOFIA will just be coming on line, and will be the only US observatory working in the 28 to 60 micron region for over 10 years: • Such once in a life time objects as Comets and Supernovae • Variable sources (AGN, X-ray sources) • New Discoveries from other Missions and Observatories

26. Leveraging the Spitzer Legacies • High spatial resolution FORCAST, FIFI-LS, & HAWC observations of SINGS galaxies resolve embedded star formation. • circumnuclear and (partial) disk mapping of ~10 sources (1-2 flights) with FIFI-LS • Resolve confused or saturated galactic plane regions in GLIMPSE survey • High spatial & spectral (accretion /jet diagnostics) observations of C2D protostars (EXES, FORCAST grism) • High resolution maps of bright disks and spectra (e.g. H2 gas search with EXES) of FEPS post-planetary disks.

27. SOFIA and Herschel • Herschel is a very sensitive, relatively short lived Mission that will tend to concentrate on surveys • SOFIA is a long lived Observatory • For the years of overlap, SOFIA will be only program with: • 25 to 60 micron capability including imaging, medium and high resolution spectroscopy. • High resolution spectroscopy in the 60 to 150 micron region. • When cryogens run out in Herschel in ~2011 SOFIA will be only NASA mission in 25 to 600 micron region for many years • Will have similar sensitivities: Important follow-up • Future instrumentation will give unique capabilities to SOFIA: Polarization, Heterodyne Arrays and better mapping sensitivity, Heterodyne Spectroscopy at 28 microns (ground state of molecular hydrogen), and many other interesting astrophysical lines.

28. SOFIA and JWST • JWST is a very sensitive mission that will study the earliest stars and galaxies that were formed • SOFIA will help better understand nearby stars and galaxies especially through its high resolution spectroscopy and the dynamics of gas. • In Addition: • Before JWST is deployed and after Spitzer cryogens run out, SOFIA is only mission with 5 to 8 micron capabilities which allows study of important organic signatures • After JWST is launched SOFIA is the only mission to provide complementary observation beyond 28 microns and high resolution spectroscopy in 5 to 28 micron region

29. Operations Plans

30. SOFIA Operations Drivers • Frequent Flights: 960 science hours/year (2x KAO) • World wide deployments especially to the Southern Hemisphere will be scheduled as required by science • Both Facility and PI Instruments • Facility Instruments: Good tools, Data Pipelines and Archive: Easy for non-IR astronomer to obtain good data (New for Airborne Astronomy with SOFIA) • PI Instruments: State of the art and innovative • General Investigator program for both FSI and PI, with funded research • Robust Instrument program to allow Observatory to “reinvent itself” every few years • Unique Education and Public Outreach program

31. SOFIA Science Operations • SOFIA will be operated as an observatory open to the whole science community through peer review • 3 flights a week for ~40 weeks per year • Requires: • Efficient operation plan • Continuous access of science and mission staff to airplane • Preflight instrument simulator facilities (testing and alignment) for mission preparation • Instrument laboratories including cryogen facilities • Flight operation planning and scheduling • Rapid instrument exchange

32. Summary, Perspective, and Science Schedule • SOFIA is a World Class Observatory that will make unique far-infrared observations that are impossible from the ground and US space observatories • There has been some restructure, but elements are now better aligned with the tasks • A dedicated team is in place that is working together to make SCIENCE happen • First Science will be in 2009 • Next Instrument Call in 2009 • Community Science in 2010 • Full Operational Capability (FOC) in 2013

33. Backup SUCCESSFUL FLIGHT HOURS LIST OF SCIENCE INSTRUMENTS WHY FUTURE INSTRUMENTS

34. Successful Flight Hours (SFH) • Time spent observing or preparing to observe a celestial target • On-Source integration time (both science targets and calibrators) • Time for guide star acquisition, field identification, boresight definition, pointing calibration, focus adjustment • Time needed to turn between flight legs (“slewing” to new target), including time needed to reposition observatory to acquire Targets of Opportunity (ToOs) and occultations • Engineering time used for observatory improvement procedures (e.g., SI commissioning, pointing improvement) • Does not include time that cannot be used for science observations or that could potentially be used for observations but is not scheduled for such • Ascent and descent • Deadlegs (except for ToOs and occultations) • Time lost due to observatory problems • Time lost due to unfavorable flight conditions (turbulence) • Time lost due to unfavorable atmospheric conditions (e.g., excessive water vapor precludes any useful observations with the mounted SI)

35. Instrument/ PI Instrument Type Location Dunham HIPO/Lowell .3-1.1 µm High Speed Occultation Camera FLITECAM**/ McLean 1-5.5 µm Infrared Camera and IR channel for HIPO UCLA FORCAST**/ Faint Object Infrared Camera. Simultaneous Dual channel Herter Cornell observations (5-25 µm & 25-40 µm) Hi resolution (R> 106) Heterodyne Spectrometer GREAT/MPI- Güsten 3 bands - 1.6-1.9 THz; 2.4-2.7 THz; 4.7 THz Bonn FIFI-LS**/ Dual Channel (42-110 µm ; 100-210 µm) Poglitsch MPI Garching Grating Spectrometer HAWC**/ High Angular resolution 4 channel Camera @ Harper UChicago 50 µm, 100 µm, 160 µm, 200 µm CASIMIR/ Hi resolution (R~ 106) Heterodyne Spectrometer 6 Zmuidzinas Caltech 500-2000 GHz Lacy EXES/UTexas 5-28 µm-High resolution grating spectrometer (R>100,000) Fabry-Perot Spectrometer 100-655 µm (2000<R<104) Moseley SAFIRE/GSFC ** Facility Instruments

36. Future Instrumentation • Technology advances rapidly in the far infrared due to increases in sensitivity and detector array sizes and we can expect a factor 10 increase in observing “speed” every 5 years • As an airborne program, SOFIA has a major instrumentation component with a planned major upgrade of an existing instrument or a new instrument every year at a cost of ~$7 million/year • Thus, SOFIA evolves into a completely new mission in ~5 yr at only the low cost of the instrument development program