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NASA's SOFIA: Stratospheric Observatory for Infrared Astronomy

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NASA's SOFIA: Stratospheric Observatory for Infrared Astronomy NASA’s SOFIA: Stratospheric Observatory for Infrared Astronomy" D. Backman! SOFIA Outreach / NASA Ames / SETI Institute! MIRA & MPC – November 7, 2015! Outline:" Infrared light & infrared astronomy" Airborne astronomy & SOFIA’s development" SOFIA in operation" Selection of SOFIA science highlights " 2015 Pluto occultation observations" Airborne Astronomy Ambassadors program" William Herschel" Discovery of Infrared Radiation - 1800 ! Getting a more complete picture:! Constellation Orion left: view at visual wavelengths right: far-infrared view! BUT INFRARED ASTRONOMY IS DIFFICULT FROM EARTH’S SURFACE…! Gamma! X-ray! UV! Infrared! ATMOSPHERE OPACITY VERSUS WAVELENGTH! Mid-Infrared image of Earth from a weather satellite View of troposphere / stratosphere boundary (tropopause) from above! 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. " " 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 Putting it together - L-3 Communications Integrated Systems, Waco, Texas! ^ 1977 >! < 2007! 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 • 2-4 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)" SOFIA Light Path Secondary mirror Spherical bearing CABIN! Light tube Infrared IR light reflection instrument Visible light reflection Primary mirror Visible- wavelength camera " View aft past the Mission Directors’ console." " The telescope is beyond the blue bulkhead." " The science instrument & counterweight are seen at center-rear. " Nov. 4! flight plan! 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) First 100%-Open Door Test Flight December 2009! Video of telescope door opening! SOFIA advantages rel. to the Hubble Space Telescope:" IR: objects cooler than normal stars like the Sun" IR: objects inside or behind interstellar dust clouds" IR: organic molecules in space" Mobility: Solar system objects occulting background stars" " SOFIA rel. to the Herschel Space Observatory:" SOFIA has six 1st-Gen instruments vs. Herschel’s three" SOFIA will have 2nd-, 3rd- and 4th-generation instruments." SOFIA’s design lifetime of 20 years vs. Herschels 4 years! Hubble Space Telescope! Herschel Space Observatory! SOFIA! JUPITER" May ‘10! 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! 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" Protostar in Rho Ophiuchi! star formation region – background! source for absorption spectra! OD and SH molecular radicals! are involved in chemical pathways leading to the formation of water and organic molecules.! 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" Sagittarius A East" Supernova (SN) Remnant" " SOFIA/FORCAST 31 µm: Yellow contours in main image; orange color in inset" " Red dashed oval indicates position of SN shock." " Detection of SN-produced dust grains surviving extreme post-SN environment." " Lau et al. 2015 (Science)" " " 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." Pluto occultation observations" 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 " Go anywhere on Earth to reach " Motion of Occulting Object Object 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 2011 Pluto" occultation" “light curve”" observed by" SOFIA." Pluto & Earth Occultation Animation! Aircraft & Occultation Shadow Animation! 2015 Pluto" occultation" shadow track" Video - onboard SOFIA 30 June 2015! 2015 occultation light curve! Pluto" hearts" you," and …" The Heart is craterless, and at its edge are folded mountain belts … tectonic activity!! Internal activity could be what sustains Pluto’s atmosphere. ! Airborne Astronomy! Ambassadors program! Airborne Astronomy Ambassadors Goals: Educators come to improved understanding of scientific research processes, and pass that understanding along to their students, colleagues, and fellow citizens Teams of educators: formal (classroom) educators, informal (museum, etc.) educators, and public outreach specialists (e.g. amateur astronomers) are selected to fly and work on SOFIA as partners with teams of researchers. Chosen via national calls for applications, aligned with observing CfPs Criteria in peer review of AAA proposals: • Quality of plans for post-flight impact back home • Geographic and demographic diversity Ambassadors trained to understand flight research project, involved in SOFIA flight series with research partners. Airborne Astronomy Ambassadors Ambassadors are supported by SOFIA Outreach after flights to fulfill their proposed STEM education & public engagement initiatives back in their home communities. Ambassadors become a growing on-line support community. ! For further information: ! ! SOFIA Science Center home page & Education 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 me:" • dbackman@sofia.usra.edu! !.
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