SOFIA Stratospheric Observatory For Infrared Astronomy Jon Morse

SOFIA Stratospheric Observatory For Infrared Astronomy Jon Morse / Ray Taylor NASA Program Executive May 11, 2007

Outline of Material • • • 2 Overview of SOFIA Progress to Date Science Operations Plans Schedule

OVERVIEW

Overview of SOFIA • SOFIA is 2. 5 m telescope in a modified B 747 -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 • Joint Program between the US (80%) and Germany (20%) • First Light Science 2009 (NASA, DLR, USRA, DSI) – – Designed for 20 year lifetime Deployments Ramp up to goal of 120 flights per year of 8 to 10 Hours Build on KAO Heritage • Science flights to originate from NASA Dryden Flight Research Center (DFRC) – DFRC is where many other NASA research aircraft are located • Science Center is located at NASA Ames Research Center 4

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PROGRESS TO DATE

Telescope Installed 7

Main Deck, Looking Aft at Instrument Interface Orange Color is Flight Test Instrumentation Telescope Pointing Control Electronics to the Left 8

Instrument Interface Blue is DLR Supplied Equipment White is New Pressure Bulkhead 9

First Flight (April 2007) Waco, TX 10

SOFIA’s Instrument Complement As an airborne mission, SOFIA supports a unique, expandable instrument suite • SOFIA covers the full IR range with imagers and low, moderate, and high resolution spectrographs • 4 instruments at Initial Operations; 9 instruments at Final Operations. • SOFIA can take fully advantage of improvements in instrument technology • Both Facility and PI Instruments • Germany is supplying two of the generation instruments (GREAT & FIFILS) 11

Three of Seven U. S. Instruments One of Two German 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 12

First Light Tracking: <0. 8 arcsec rms from ground (September 2004) 13

SCIENCE

Science Capabilities • Because of large aperture and better detectors, sensitivity for imaging and spectroscopy similar to the space observatory ISO • 8 x 8 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 15

Astrochemistry • Most molecular lines in IR or submillimeter • Need high spectral resolution throughout IR and submillimeter • As sensitive as CSO, but complete wavelength range is accessible (ie. H 2, C 2 H 2, CH 4 only in IR) • Light molecules: Hydrogen, water, other hydrides in IR and submillimeter • HD at 112 microns • The fullerene, C 60, has 4 IR lines in SOFIA’s bands 16 CSO FTS Spectrum of ORION OMC 1 Serabyn and Weisstein 1995

Occultation astronomy with SOFIA will measure stellar occultations 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 17

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 Astronomers at ESO and Keck detected fast moving stars revealing a 4 x 106 solar mass black hole at the Galactic Center • • 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? 18

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? • As pointed out by Bergin, Hollenbach and others, HD can also give the Molecular Hydrogen abundance. NASA strategic sub-goal 3 D. 1 and 3 D. 2 19

Operations Plans

SOFIA Operations Drivers • Frequent Flights: Ramp Up to 960 science hours/year (2 x 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 21

SOFIA Science Operations • SOFIA will be operated as an observatory open to the whole science community through peer review • Ramp Up to 3 flights a week for ~40 weeks per year • On-going independent review of SOFIA science operations – Gary Melnick, Chair • 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 – – – 22 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

Schedule

SOFIA Schedule (Major Milestones) 24 Completed • First Re-Flight April ‘ 07 Upcoming • Ferry Flight to DFRC • Initiate Closed Door Flight Tests • Complete Closed Door Flight Tests • Install Door Drive (and other work) • Initiate Open Door Flight Tests • First Science June ‘ 07 Fall ‘ 08 Summer ‘ 08 Fall/Winter ‘ 08 Spring ‘ 09

FY 08 Budget Request 25 SOFIA FY 08 FY 09 FY 10 FY 11 FY 12 Total 77. 3 89. 1 88. 6 89. 9 92. 1

Summary 26 - Aircraft structural modifications complete - Telescope installed, several instruments tested on ground observatories - Several subsystems to be installed (e. g. , door drive) - Completed first flight, leading to ferry flight in June ‘ 07 to DFRC - Full envelope flight testing (closed door) to start in Fall ’ 08 - First science in ’ 09 - SOFIA will be one of the primary facilities for far-IR and sub-millimeter astronomy for many years

Back-up

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 FY 09, SOFIA will be the only observatory working in the 25 to 60 micron region for over 10 years: Comets, Supernovae, Variable AGN, other discoveries. 28

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 29

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 30

Why SOFIA? • • • 31 Atmosphere: above 99% of the water vapor IR transmission at 14 km >80% from 1 to 800 m Instrumentation: wide variety, rapidly interchangeable, state-ofthe art Mobility: anywhere, anytime Long lifetime A near-space observatory that comes home after every flight

NEXT CALL FOR NEW INSTRUMENTS • • 32 The next call for instruments will be at first Science ~FY 10 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

Infrared Space Observatories SPITZER SOFIA ? 3 JWST 10 30 1 Ground-based Observatories 33 2005 2010 2015 2020 2025 SOFIA provides temporal continuity and wide spectral coverage, complementing other infrared observatories. Frequency (THz) 100 SAFIR 0. 3 Herschel Wavelength (µm) 1000