SOFIA Stratospheric Observatory For Infrared Astronomy E.E. Becklin SOFIA Chief Scientist Astrobiology Workshop Jan 07, 2009

Outline of Material Overview of SOFIA Progress to Date Astrobiology Science

OVERVIEW

Overview of SOFIA SOFIA is 2.5 m telescope in a modified B747SP aircraft Optical-mm performance Can obtain obscured IR (30-300 m), most important Joint Program between the US (80%) and Germany (20%) First Science 2009 (NASA, DLR, USRA, DSI) Designed for 20 year lifetime

Overview of SOFIA (Cont) 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 Palmdale ….Aircraft operation by NASA Dryden Research Center (DFRC) Science Center is located at NASA Ames Research Center

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

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

PROGRESS TO DATE

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

SOFIA in the Palmdale Hanger

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 to high resolution spectrographs 5 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.

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

Astrobiology Science

Science Capabilities Because of large aperture and better detectors, sensitivity for imaging and spectroscopy similar to the space observatory ISO but with higher spectral and angular resolution. 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

Planetary Atmospheres SOFIA will determine the Methane on Mars 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 line on Mars How much methane is on Mars? Does it show biogenic activity? What are the spatial and seasonal variability? The near-infrared groundbased spectrum of Mars (left panel) is dominated by strong absorption bands in the earth atmosphere. The much weaker lines due to molecules in the atmosphere of Mars are displaced due to the Doppler effect and are indicated by a +. The right panel shows a blow up of a portion of the terrestrial methane line. The wiggle on this line may indicate the Martian methane line.

How does the chemistry of disks vary with radius? High spectral resolution can determine where species reside in the disk; small radii produce double-peaked, wider lines. Observing many sources at different ages in this way will trace the disk chemical evolution 17

SOFIA is Well-matched to Astrochemistry 18

SEARCHING FOR LARGE CARBON RINGS Do Large Carbon Rings form in the Interstellar Medium? Lab studies show that moderate resolution (R=200-1000) spectroscopy from 5-200 m is a key to finding the large carbon molecules. (Large PAH) Discovery might be possible with an advanced instrument on SOFIA that works over the entire wavelength range. High resolution follow up using GREAT & CASIMIR can resolve P-Q-R branch structure of lowest vibrational transitions 19

Summary SOFIA will be one of the primary facilities for far-IR and sub-millimeter astronomy for many years

Back-up

.3-1.1 µm High Speed Occultation Camera FLITECAM**/ McLean Instrument/ PI Instrument Type Location HIPO/Lowell Dunham .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) GREAT/MPI- Hi resolution (R> 106) Heterodyne Spectrometer Güsten Bonn 3 bands - 1.6-1.9 THz; 2.4-2.7 THz; 4.7 THz 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 EXES/UTexas Lacy 5-28 µm-High resolution grating spectrometer (R>100,000) SAFIRE/GSFC Moseley Fabry-Perot Spectrometer 100-655 µm (2000<R<104) ** Facility Instruments