NASA and the DLR (German Aerospace Center) are collaborating to create SOFIA, the Stratospheric Observatory for Infrared Astronomy--a Boeing 747-SP aircraft modified by L-3 Communications Integrated Systems in Waco, Texas to accommodate a 2.5-meter reflecting telescope, approximately the same size as the Hubble Space Telescope. SOFIA will be the largest airborne observatory in history, and will make observations that are impossible for even the largest and highest ground-based telescopes.

Astronomical objects emit many forms of energy, which neither the human eye nor ordinary telescopes can detect. SOFIA will be the world's primary observatory at far-infrared and sub-millimeter wavelengths for much of the next two decades, capable of "Great Observatory"-class science. SOFIA will also be an outstanding laboratory for developing and testing astronomical instrumentation and detector technology, as well as an education and public outreach facility "par excellence", putting educators from across the U.S. in contact with frontier scientific research.

NASA Administrator Michael Griffin announced on July 6, 2006 that NASA planned to go forward with completing and operating SOFIA. NASA's Dryden Flight Research Center (DFRC) has over-all responsibility for the remainder of SOFIA's development. A SOFIA "Science Project" at NASA's Ames Research Center including Universities Space Research Association (USRA) will continue planning for scientific operations and management of SOFIA's nine science instruments. DLR and the Deutsches SOFIA Institut (DSI) at the University of Stuttgart will continue support for telescope maintenance and science operations.

The SOFIA telescope is already functioning and has been used for optical test observations of Polaris from the L-3 runway apron. In September 2006 SOFIA taxied under its own power for the first time since arriving in Waco in 1997. Both low- and high-speed taxi tests have been done, as well as full power engine run-ups. Later that month, upgrades were completed to a critical bulkhead in the tail. The plane has now received its flight-worthy paint job, with registered "tail number" N747NA.

Principal efforts remaining before first test flight include: completion of about 400 "routine" aircraft maintenance items, installation of the telescope cavity insulation, modification and verification of the cavity environmental control system, avionics verification, installation of some safety monitoring and flight-test systems, and safety and flight readiness reviews. The plane is expected to fly from Waco to DFRC after a few airworthiness test flights, sometime in spring 2007. Several years of test flights are planned at DFRC, first a series of flights with the telescope door closed, followed by a series with the door open. After that will come scientific commissioning of the observatory and the first astronomical research observations, which the current schedule indicates will occur in late 2009.