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SOFIA Completes First Flight of German Science Instrument
Photos below
April 7, 2011
The Stratospheric Observatory for Infrared Astronomy, or SOFIA, completed its first science flight using the German Receiver for Astronomy at Terahertz Frequencies (GREAT) scientific instrument on Wednesday, April 6. GREAT is a high-resolution far-infrared spectrometer that finely divides and sorts light into component colors for detailed analysis.
SOFIA is the only operational airborne observatory. It is a joint program between NASA and the German Aerospace Center (DLR). The observatory is a heavily modified Boeing 747SP aircraft carrying a reflecting telescope with an effective diameter of 100 inches. Flying at altitudes between 39,000 and 45,000 feet, above the water vapor in Earth's lower atmosphere that blocks most infrared radiation from celestial sources, SOFIA conducts astronomy research not possible with ground-based telescopes.
"SOFIA's onboard crew seamlessly combined scientists, engineers and technicians from the U.S. and Germany, working together on an observatory developed in the U.S., using a telescope and instrument built in Germany, to gather data of great interest to the entire world's scientific community," said Bob Meyer, NASA's SOFIA Program manager at the agency's Dryden Flight Research Center in Edwards, Calif.
GREAT Principal Investigator Rolf Guesten of the Max Planck Institute for Radio Astronomy in Bonn, Germany, and his team conducted observations high above the central and western United States beginning the night of April 5 with their instrument installed on SOFIA's telescope.
Among their targets were IC 342, a spiral galaxy located 11 million light-years from Earth in the constellation Camelopardalis ("The Giraffe"), and the Omega Nebula (known as M17), 5,000 light-years away in Sagittarius. The team captured and analyzed radiation from ionized carbon atoms and carbon monoxide molecules to probe the chemical reactions, motions of matter and flows of energy occurring in interstellar clouds. Astronomers have evidence such clouds in both IC 342 and M17 are forming numerous massive stars.
"These first spectra are the reward for the many years of work creating this technology, and underline the scientific potential of airborne far-infrared spectroscopy," Guesten said.
GREAT focused on strong far-infrared emissions from interstellar clouds that cool the clouds. The balance between heating and cooling processes regulates the temperature of the interstellar material and controls initial conditions for the formation of new stars.
"These observations give us unique information about the physical processes and chemical conditions in the stellar nurseries," said Juergen Stutzki, a co-investigator on the GREAT team. "SOFIA will give us new and deep insight into how stars form."
GREAT, one of two German first-generation SOFIA scientific instruments, was developed by the Max Planck Institute for Radio Astronomy and the University of Cologne in collaboration with the Max Planck Institute for Solar System Research and the DLR Institute of Planetary Research.
"This first science flight with a German instrument is a huge milestone for the SOFIA observatory," said John Gagosian, SOFIA program executive at NASA Headquarters in Washington. "GREAT, in combination with SOFIA's other German and U.S.-developed instruments, demonstrates SOFIA's extraordinary versatility, allowing it to play a unique and essential role alongside the Spitzer and Herschel spacecraft."
NASA's Ames Research Center in Moffett Field, Calif., manages the SOFIA science and mission operations in cooperation with the Universities Space Research Association headquartered in Columbia, Md., and the German SOFIA Institute at the University of Stuttgart, Germany. SOFIA is based and managed at Dryden's Aircraft Operations Facility in Palmdale, Calif.
Trent Perrotto
NASA Headquarters SMD
Cathy Weselby
NASA Ames Research Center
Beth Hagenauer
NASA Dryden Flight Research Center
Nick Veronico
SOFIA Science Center
For more information about SOFIA, visit:
http://www.nasa.gov/sofia • http://www.dlr.de/en/sofia
For information about SOFIA's science mission, visit:
http://www.sofia.usra.edu • http://www.dsi.uni-stuttgart.de/index.en.html
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The German Receiver for Astronomy at Terahertz Frequencies spectrometer, or GREAT, is mounted on the Stratospheric Observatory for Infrared Astronomy's telescope in its normal position. When observing, the instrument will move with the telescope plus or minus 20 degrees from its normal 40-degree angle.
January 21, 2011.
NASA Photo / Tom Tschida
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High-resolution far-infrared spectra of the nebula Messier 17 (M17) obtained with the GREAT spectrometer and SOFIA on the night of April 5-6, 2011, superimposed on a Spitzer near-infrared image. The white spectra are C II (singly-ionized carbon) and the green spectra are CO (carbon monoxide). The two panels at bottom show maps of C II and CO emission intensity within the red box in the upper panel. (Spectra and spectral maps: GREAT Team/NASA/DLR/USRA/DSI; Background IR image: NASA/JPL-Caltech/Spitzer)
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IC 342 is the nearest gas-rich spiral galaxy with active star formation in its nucleus. Within its central 30 arc seconds, two arms of molecular gas end in a clumpy central ring of dense gas surrounding a young star cluster. The young stars heat the local gas and dust, causing complex chemical reactions as well as intense infrared emission from these regions. These types of clouds are also called photon dominated regions (PDR). The strong emission from these PDRs allows an in-depth study of the chemical and physical conditions in these distant massive star-forming regions.
(Optical wavelength image credit: Ken and Emilie Siarkiewicz/Adam Block/NOAO/AURA/NSF; please note that this image is presented here for explanatory purposes, it was not made by SOFIA/GREAT)
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M17SW is a molecular cloud containing about 10000 solar masses of gas. The cloud is illuminated by a cluster of young stars with a total luminosity of more than one million times that of our sun. Radiation from the young star cluster ionizes and heats the molecular gas, possibly compressing it in such a way that more stars form from the compressed gas. The SOFIA observations with the GREAT spectrometer can distinguish the effect of radiative compression from the heating effect that would instead lead to expansion and dispersal of the cloud. In this way, analysis of GREAT spectra can predict the future of the molecular cloud with regard to its star formation activity.
(infrared image credit: NASA/JPL-Caltech/Spitzer; please note that this image is presented here for explanatory purposes, it was not made by SOFIA/GREAT)
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For additional information about the GREAT instrument and SOFIA's April 5-6 science flight, go to the German Aerospace Center (DLR)'s news release (in English):
http://www.dlr.de/en/desktopdefault.aspx/tabid-4220/6776_read-30074/
Also, see the NASA HQ mission page for SOFIA:
http://www.nasa.gov/mission_pages/SOFIA/ |
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Page Last Updated:
January 25, 2012
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