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16Feb CAG Conf NASA’s SOFIA: Stratospheric Observatory for Infrared Astronomy" D. Backman! SOFIA Outreach / NASA Ames / SETI Institute! Outline:" Infrared light & infrared astronomy" SOFIA’s engineering development" SOFIA in operation" SOFIA science highlights " Airborne Astronomy Ambassadors" William Herschel" Discovery of Infrared Radiation - 1800 ! Getting a more complete picture:! Constellation Orion left: view at visual wavelengths right: far-infrared view! Representing invisible light is as much art as science.! Special capabilities of an infrared observatory:" " Study objects cooler than normal stars," "e.g. stars & planets forming" " Study objects inside or behind interstellar dust clouds" Study organic molecules in space" " View of troposphere / stratosphere boundary (tropopause) from above! Mauna Kea observatories! Evolution of NASA’s Airborne Telescopes" LearJet! 10-inch! Kuiper! Airborne! Observatory! 36-inch! SOFIA! 100-inch! Aircraft flying above about 40,000 ft" can observe most of the infrared universe. Airborne infrared telescopes can be more versatile – and much less expensive -- than space infrared telescopes. " " SOFIA: An Engineering Marvel" How does SOFIA work?" Airborne observatory has 3 critical parts:! ! • Boeing 747SP aircraft that must fly at 41,000+ ft! !for 10 – 12 hour missions! • 17 M-ton reflecting telescope that must be able to point precisely at targets in the universe! • Interchangeable Science Instruments that must be able to make sensitive infrared measurements! Component 1: The Aircraft" NASA’s Kuiper Airborne Observatory (KAO)" ,! The KAO, a C-141 with a 0.9-meter (36-inch) telescope onboard, was based at NASA-Ames near San Jose and flew from 1975 to 1995 Studies of cavity acoustics: SOFIA 7%-scale model in NASA Ames 14-ft transonic wind tunnel ^ 1977 >! < 2007! SOFIA on its way to Waco, TX to get chopped:" video of telescope door opening! Component 2: The Telescope" SOFIA Light Path Secondary mirror Spherical bearing CABIN! Light tube Infrared IR light reflection instrument Visible light reflection Primary mirror Visible- wavelength camera Putting it together - L-3 Communications Integrated Systems, Waco, Texas! Telescope cavity, with door open:" Component 3: Science Instruments" Four First-generation Instruments FLITECAM near-IR camera w/ grism HIPO (UCLA) UV / visual / near-IR fast photometer (Lowell Observatory) GREAT far-IR spectrometer (MPIfR) FORCAST mid-IR camera w/ grism (Cornell) SOFIA Science Instrument “footprints” in spectral resolution versus wavelength! SOFIA in operations" SOFIA -- The Next Generation Airborne Observatory! • 2.5-meter (100-inch) diameter telescope in a Boeing 747SP • Based at NASA-Armstrong facility in southern Calif., with mission science center at NASA-Ames in northern Calif. • 20% share with the German space agency DLR • First science flight was in 2010 • Goal: 120+ 8-hr science flights per year, 20-yr lifetime • 4-7 weeks per year in Southern Hemisphere deployments SOFIA – the observatory! Open cavity ! Educator work stations" (door not shown)! Pressure bulkhead" Scientist work stations, TELESCOPE" telescope and instrument control, etc." Scientific instrument (1 of 6)" " View aft past the Mission Directors’ console." " The telescope is beyond the blue bulkhead." " The science instrument & counterweight are seen at center-rear. " Sample Flight Plan! Pointing the telescope: Floating on spherical bearing; Orientation sensed by gyroscopes; Optical TV cameras view field near target! SOFIA: A Scientific Marvel" JUPITER" W3A in Perseus" " Compact HII region &" massive protostar cluster" " [inset]" SOFIA/FORCAST" 7.7, 20, 32 µm" ~ 1.5 x 1.0 pc" " [background]" Spitzer/IRAC" 3.6, 4.5, 7.9 µm" " Note bubble at left, cleared by winds from young O stars in the cluster, resolved by SOFIA." " Salgado et al. 2012 (Ap.J.)" " Hi-resolution deconvolution" by J. De Buizer" Images of the Milky Way Galaxy’s nucleus Ring of molecular clouds orbiting ! central supermassive black hole.! [Only massive central star cluster is seen.]! SOFIA: mid-IR" Hubble: near-IR" M82 - SN 2014J" " SOFIA/FLITECAM+grism" 1.5 – 2.7 µm" " Co II emission" @ 1.77 µm" FWHM ~ 12,000 km s-1" " Two epochs:" to + 36 days" to + 44 days" " SN2014J((Op,cal)( Vacca et al. 2015 (Ap.J.)" " Insets: [left] SOFIA/ FLITECAM J,H,K image of M82, arrow points to SN 2014J" [right] Optical light curves; epoch of first SOFIA observation indicated." MARS" " SOFIA/EXES" H20 & HDO @ 7.2 µm" R ~ 85,000" " Disk-integrated spectrum compared with terrestrial atmosphere transmission" " Ratio of HDO to H2" confirms wetter Mars" in the past." " Encrenaz et al. 2015" (submitted to A&A)" " ! Insets:" (left) EXES on SOFIA telescope! (right) Mars 7.2 µm continuum map! Stellar Occultations" SOFIA is able to:! ! Probe the sizes," structures (rings & moons), and " "atmospheres of solar system " "bodies by measuring how they " Toward "occult background stars." Occulted Star " Can go anywhere on Earth to " Motion of Occulting Object Object reach the occultation shadow" "of a Solar System object." Shadow of Occulting Object Earth The rings of Uranus – discovered via occultation observations by SOFIA’s predecessor, the KAO. Star behind Rings were discovered Uranus and rings via occultations of a background star 2015 Pluto" occultation" shadow track" video of SOFIA Pluto observations! 2015 occultation light curve! Airborne Astronomy Ambassadors" 2011: First Airborne Astronomy Ambassador educators! Mary Blessing, Herndon, Va. " Pamela Harman (SETI) with Margaret Piper, Frankfort, Ill. " Cris DeWolf, Remus, Mich. with Dana Backman (SETI)" Kathleen Fredette, Palmdale, CA" Theresa Paulsen, Mellen, Wis. and Marita Beard, San Jose, Calif. " Cecilia Scorza (DSI) with Wolfgang Vieser, Munich, Germany" with Coral Clark (USRA)" Jörg Trebs, Berlin, Germany" 22 Educators Selected for the Cycle 4 AAA" Program (flights in 2016), Including:! Marie Thornsberry, Hughbanks Elementary, Rialto CA Wendi Rodriquez, The Heritage School, Phelan CA JOBS IN THE SOFIA PROGRAM" (Many career paths lead here…)! Scientists & mathematicians 40 Engineering incl. software & IT 70 Aircraft incl. pilots & mechanics 30 Business & accounting 40 Admin & admin assistants 25 Outreach 10 TOTAL 215 ! For further information: ! ! ! SOFIA Science Center home page & EPO main page! • http://www.sofia.usra.edu! • http://www.sofia.usra.edu/Edu/edu.html! ! Spitzer Space Telescopes award-winning infrared tutorial! • http://coolcosmos.ipac.caltech.edu! (includes instructions for home-made Herschel demo)! ! To contact the presenter:! • dbackman@sofia.usra.edu! !.
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