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2 SOFIA Stratospheric Observatory For Infrared Astronomy E. E. Becklin SOFIA Chief Scientist October, 2007

3 Outline Overview of SOFIA Progress to Date Science Schedule

4 OVERVIEW

5 Overview of SOFIA SOFIA is 2.5 m telescope in a modified B747SP aircraft –Optical-mm performance –The obscured IR (  m) is most important Joint Program between the US (80%) and Germany (20%) First Science 2009 (NASA, DLR, USRA, DSI) Designed for 20 year lifetime

6 Overview of SOFIA (continued) Operating altitude –39,000 to 45,000 feet (12 to 14 km) –Above > 99% of obscuring water vapor World Wide Deployments Ramp up to ~1000 science hours per year Build on KAO Heritage with improvements (Facility Inst., Science Support) Science flights to originate from NASA Dryden Flight Research Center (DFRC) Science Center is located at NASA Ames Research Center

SOFIA — The Observatory open cavity (door not shown) TELESCOPE pressure bulkhead scientific instrument (1 of 9) scientist stations, telescope and instrument control, etc. Educators work station

8 Why SOFIA? Infrared transmission in the Stratosphere very good: >80% from 1 to 1000 microns Instrumentation: wide complement, rapidly interchangeable, state-of-the art Mobility: anywhere, anytime Long lifetime

9 PROGRESS TO DATE

10 Main Deck, Looking Aft at Instrument Interface Telescope Installed Major Physical Installations Completed

11 Spherical Bearing “First Oil“ The Bearing Sphere on the Nasmyth Tube Rotation Isolation Subsystem

12 Primary Mirror (uncoated)

13 Telescope in Action

14 SOFIA rms Tracking of <0.8 arcsec

15 SOFIA Makes Its First Flight!

16 SOFIA Arrival at NASA DFRC, May 31, 2007

17 As an airborne mission, SOFIA supports a unique, expandable instrument suite SOFIA covers the full IR range with imagers and low to high resolution spectrographs 4 instruments at Initial Operations; 9 instruments at Full Operations. SOFIA will take fully advantage of improvements in instrument technology. There will be one new instrument or major upgrade each year. SOFIA’s Instrument Complement

18 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 Four First Light Instruments

19 SCIENCE

20 Science Capabilities Because of large aperture and better detectors, sensitivity for imaging and spectroscopy similar to the space observatory ISO 8x8 arcmin Field of View allows use of very large detector arrays Image size is diffraction-limited beyond 25 µm, making it 3 times sharper than the space observatory Spitzer at these wavelengths

21 Astrochemistry Most ground state molecular lines in IR or submillimeter Need high spectral resolution throughout which SOFIA has. As sensitive as CSO, but much larger wavelength range is accessible Light molecules: Molecular hydrogen, HD, water, other hydrides in IR and submillimeter The fullerene, C 60, has 4 IR lines in SOFIA’s bands CSO FTS Spectrum of ORION OMC1 Serabyn and Weisstein 1995 SOFIA is an outstanding observatory to study chemistry in space

22 Occultation astronomy with SOFIA Pluto occultation lightcurve observed on the KAO (1988) 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 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 fixed observatories. SOFIA will determine the properties of Dwarf Planets in and beyond the Kuiper Belt

23 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 high and may reflect biogenic activity. EXES working at 7.6 microns in the Stratosphere will be able to see directly the Doppler-shifted methane lines on Mars How much methane is on Mars? Does it show biogenic activity? What are the spatial and seasonal variability? SOFIA will determine the Methane on Mars Planetary Atmospheres

24 Today over 200 extrasolar planets are known, and over 15 transit their primary star 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 and before JWST. 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, satellites, and/or planetary rings Artist concept of planetary transit and the lightcurve of HD b measured by HST revealing the transit signature SOFIA will determine the properties of new extrasolar planets by use of transits with HIPO and FLITECAM working together Extrasolar Planet Transits

25 Astronomers at ESO and Keck have detected fast moving stars revealing a 4 x 10 6 solar mass black hole at the Galactic Center One of the major discoveries of the KAO was a ring of dust and gas orbiting the very center of the Galaxy at r=1pc Young newly formed stars have also been found orbiting the black hole within 1000au Did these young massive stars form in the ring of dust and gas? If so, how do they get so close to the black hole? Are there other ways that the massive stars could form? SOFIA with its high angular and spectral resolution is well placed to help answer these questions over the next 20 years SOFIA will help determine how stars form in the presence of a Massive Black Hole Star Formation in the Center of the Galaxy in the Presence of a Massive Black Hole

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

27 Atmospheric transmission around the HD line at 40,000 feet Deuterium in the universe is created in the Big Bang. Measuring the amount of cold HD (T<50K) can best be done with the ground state rotational line at 112 microns. Detections with ISO means a GREAT high resolution spectrometer study possible. As pointed out by Bergin and Hollenbach, HD gives the cold molecular hydrogen. HD has a much lower excitation temperature and a dipole pole moment that almost compensates for the higher abundance of molecular hydrogen. In the future could be used much like the HI 21cm maps but for cold molecular gas. SOFIA will study deuterium in the galaxy using the ground state HD line at 112 microns. This will allow determination the cold molecular hydrogen abundance. Cold Molecular Hydrogen using HD

28 SOFIA: Science For the Whole Community

29 SCHEDULE

30 SOFIA Schedule (Major Milestones) First Re-Flight Occurred April ‘07 Door Drive Delivered Winter ‘07 Open Door Flights at DFRC Fall ‘08 First Science ‘09 Next Instrument call ‘10

31 US General Observer Opportunities First call for science proposals in ‘09 Future calls every 12 months First General Observers 2010 –Expect ~ 20 General Observer science flights –Shared risk with Instrument PI’s Open Observatory with Facility Instruments

32 Next Call for New Instruments The next call for instruments will be at first Science ~FY10 There will be additional calls every 3 years There will be one new instrument or upgrade per year Approximate funding for new instruments $8 M/yr

33 NASA Ames and USRA are ramping up for Observatory operations. Please visit the SOFIA web site ( for Job opportunities. There will be community involvement in the Early Science Program. We will hold a “SOFIA’s 2020 Vision” Workshop at Caltech, December 6-8, 2007 – long term science We will hold a “SOFIA Early Science” Workshop at the January AAS meeting in Austin, TX, January 8, 2008 Preparations for Science Operations and Community Task Force Activities

34 Summary Program making progress! –Aircraft structural modifications complete –Telescope installed, several instruments tested on ground observatories –Completed first flight and ferry flight to NASA Dryden –Full envelope flight testing (closed door) has started. –Several subsystems will be installed spring/summer 08 (Door motor drive, coated primary mirror) –First science in ’09 SOFIA will be one of the primary facilities for far-IR and sub- millimeter astronomy for many years

35 BACK-UP

36 OPERATIONS PLANS

37 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

38 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 Flights will be primarily out of Dryden (Edwards AFB) with occasional deployments to the southern hemisphere and other sites as needed –Continuous access of science and mission staff to airplane –Preflight instrument simulator facilities (testing and alignment) for mission preparation –Instrument laboratories including cryogen facilities –Rapid instrument exchange Science center will be at Ames –Telescope time peer review –Observing time schedule –Flight planning –Management of Instruments (Operations and Development) –Science Data Archive(Facility Instruments Reduced data, PI raw data) –Observing Support

39 SOFIA and Spitzer SOFIA will become operational near the time that Spitzer runs out of cryogens. The science impact of not being contemporary is small: Spitzer is a high sensitivity imaging and low resolution spectroscopy mission. SOFIA is a high spectral and high angular resolution mission As it now stands, the two observatories are very complementary and when Spitzer runs out of cryogens in early FY09, SOFIA will be the only observatory working in the 25 to 60 micron region for over 10 years: Comets, Supernovae, Variable AGN, other discoveries.

40 SOFIA and Herschel Herschel and SOFIA will now start at about the same time Joint calibration work is on going For the years of overlap, SOFIA will be only program –with 25 to 60 micron capability –with 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 –Important follow-up –Advanced instrumentation will give unique capabilities to SOFIA: Polarization, Heterodyne Arrays, Heterodyne Spectroscopy at 28 microns (ground state of molecular hydrogen), and other interesting astrophysics lines Both missions are critically important and complementary

41 SOFIA and JWST SOFIA is very complementary to JWST Before JWST is deployed and after Spitzer cryogens run out, SOFIA is only mission with 5 to 8 micron capabilities –important organic signatures After JWST is launched SOFIA is the only mission to give complementary observation beyond 28 microns and high resolution spectroscopy in 5 to 28 micron region

42 SOFIA and WISE WISE is a very sensitive all sky survey in the 3.3 to 23 micron region. It is expect to launch just as SOFIA begins operations. SOFIA can provide a number of important follow up observations. –Very red sources seen only at 23 microns can be followed up at 38 microns with FORCAST on SOFIA and spectra can be obtained with EXES on SOFIA for the brightest 23 micron sources not seen by IRAS. –Nearby cold Brown Dwarfs discovered by WISE can be followed up with the FLITECAM GRISM and EXES.

43 Infrared Space Observatories Ground-based Observatories SOFIA provides temporal continuity and wide spectral coverage, complementing other infrared observatories. Frequency (THz) SOFIA Wavelength (µm) SPITZER Herschel SAFIR JWST ?