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NASA's airborne observatory SOFIA gets major upgrade

Paul Sutherland, Feature writer
Apr 21, 2012, 23:00 UTC

Sen—NASA is upgrading the hawk-like observing powers of one of its most important but oddest observatories - a jumbo jet.

The agency has chosen to rebuild a science instrument called HAWC to fly on the Stratospheric Observatory for Infrared Astronomy (SOFIA) an airborne telescope that is jointly operated with Germany.

We are used to these giant aircraft as the transport that carries us across the world on long-distance business trips or on exotic holidays.

Video footage this week of Space Shuttle Discovery being piggy-backed to a museum has reminded people that NASA also use a Boeing 747 to transport those spacecraft across the USA.

But fewer, perhaps, realise that one of these giant aircraft operates as one of the world's major observatories. SOFIA is a project that NASA run with the German Aerospace Center (DLR). It has adapted a Boeing 747SP to carry a 2.7 meter (106-inch) diameter telescope. A large door opens in flight to allow the instrument to observe the Universe.

Because the telescope flies at stratospheric altitudes of around 12 km (41,000 ft), it is above almost all the water vapour in the atmsphere that absorbs infrared light making it unobservable from the ground.

SOFIA can see 80 per cent of the full infrared part of the spectrum. It also benefits from being extremely manoevrable, and though based at NASA's Dryden Aircraft Operations Facility in Palmdale, California, can fly to anywhere around the globe to observe the northern or southern sky.

The new upgrade comes with an instrument called the High-resolution Airborne Wideband Camera (HAWC). This will allow the observatory to measure the structure and strength of magnetic fields in objects includuing star-forming clouds and galaxies. Its observations will help astronomers better understand how stars, planets and galaxies form and evolve.

SOFIA Science Mission Director Erick Young said: "SOFIA's infrared instruments can see into the dense clouds where stars and planets are forming and detect heat radiation from their construction material."

Dr Johannes Staguhn, of Johns Hopkins University’s Center for Astrophysical Sciences at Baltimore, Maryland, is leading the team that will provide sensitive arrays of detectors to increase HAWC's observing powers.

He said: "The role of magnetic fields in the process of star formation and the associated formation of planets is still far from being understood. The instrument upgrade will provide for the first time the capability for the SOFIA observatory to measure magnetic fields on large scales in molecular clouds."

NASA's Ames Research Center at Moffett Field, California, manages the SOFIA science and mission operations together with the Universities Space Research Association, in Columbia, Maryland, and the German SOFIA Institute at the University of Stuttgart.

NASA's Science Mission Directorate associate administrator John Grunsfeld said: "SOFIA has the ability to become a world-class airborne observatory that complements the Hubble, Spitzer and Herschel space telescopes. This upgrade will greatly broaden SOFIA's capabilities."