The Stratospheric Observatory for Infrared Astronomy (SOFIA) is a joint project of NASA and DLR, the German Aerospace Center. SOFIA is a Boeing 747SP airliner modified to carry a 2.5 meter diameter reflecting telescope for infrared astronomy observations at altitudes of about 41,000 feet (~12 km) in the stratosphere. Its flight capability will allow it to rise above almost all of the water vapor in the Earth's atmosphere (allowing observations at some infrared wavelengths which are blocked by the atmosphere before reaching ground-based facilities), as well as travel to almost any point on the earth's surface for observations. The telescope looks out of a large door in the side of the fuselage near the airplane's tail, and will initially carry nine instruments for infrared astronomy in wavelengths from 0.35–655 micrometres.

The primary science objectives of SOFIA are to study the composition of planetary atmospheres and surfaces; to investigate the structure, evolution and composition of comets; to determine the physics and chemistry of the interstellar medium; and to explore the formation of stars and other stellar objects.

SOFIA completed its first ground-based "on-sky" test on 18–19 August 2004 by taking a picture of the star Polaris. The telescope has not yet been operated on any test flights (as of March 2005). However, when testing is complete, it is hoped that observing flights will be flown 3 or 4 nights a week for the next 20 years. SOFIA will be based at NASA's Ames Research Center at Moffett Field, California (near San Jose, CA).

See also

• Infrared astronomy
• Far infrared astronomy

External links

• NASA SOFIA website
• DLR.de SOFIA website