Inside that door the telescope sits in an unpressurized part of the plane that has an effective diameter of 2.5 meters (about 8 feet). Because SOFIA only performs observation missions at night, it's often called the Vampire Jet.

Boeing 747, (SOFIA) Fixed Wing Airborne observatory ... Used as a testbed for supersonic research and to train pilots …

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The "SP" stands for Special Performance -- and it lived up to its name. Once the telescope door opens, the work can be intense. There are no relief pilots during our nearly 10-hour flight, and aside from quick trips to the lavatory and walks through the cabin, the pilots are on duty the entire journey.

There are no real breaks. But, infrared light can reach and be read by a telescope -- if it's an infrared telescope.It provides data that can't be picked up by any other telescope on the ground or in space ... at least in the known galaxy.Pamela Marcum, NASA's SOFIA project scientist, said the goals of the overall mission include "studying objects spanning the full gamut of astronomical topics including planets, moons, asteroids and comets in our solar system; star and planet formation; extra-solar planets and the evolution of planetary systems; the interstellar medium and interstellar chemistry; the nucleus of the Milky Way galaxy, and nearby normal and active galaxies. "SOFIA's signature visual cue is the bulge at the back of the fuselage. Your browser or your browser's settings are not supported. Pilot Gordon Fullerton's NASA crew for the first flight of SOFIA included copilot Bill Brockett, flight engineer Larry LaRose, and flight test engineer Marty Trout. Its instruments consist of cameras, spectrometers, and photometers. Are you with me? The telescope doesn't gather valuable data in daylight.

One pilot dons his oxygen mask as it's mandatory to wear them above 41,000 feet and SOFIA will eventually reach an altitude of 43,000 feet.As we climb, scientists run multiple checklists and prepare for the scheduled 6 hours and 55 minutes of observation time. On the flight deck, a green light on the flight engineer's panel indicates that the telescope door is open. Turbulence can cause the telescope to de-lock from its target. Get the latest updates on NASA missions, watch NASA TV live, and learn about our quest to reveal the unknown and benefit all humankind. But even during moderate, choppy turbulence, it stays stable due to its spherical bearing, shock absorbers and gyroscopes. This SP was relatively youthful in terms of hours and age. Out of more than 1,500 747s built, only 45 SPs rolled off the assembly line. The plane is based inside a former B-1 bomber plant at NASA's Armstrong Flight Research Center, in Palmdale California -- except during the Northern Hemisphere summer, when it's based at Christchurch, New Zealand. NASA purchased it on February 5, 1997. This inflight photo was taken on SOFIA's first flight since its modification to become an airborne observatory. So, the higher altitude you fly, the drier it gets and the more optimal it is for infrared observation.Allan W. Meyer, a SOFIA flight planner who has been conducting airborne astronomy since 1975, said the seasons matter as well, which is why SOFIA shifts between hemispheres to be able to observe in winter year round. Each of the 100 missions works out to nearly $1 million.

The telescope is so precisely balanced that it appears to be moving, when in fact, the airplane is moving around the telescope.

It's the best side of the aircraft for observing during westerly flight. "SOFIA is a true multi-use observatory. An employee of NASA contractor Integration, Innovation, Inc. (i3-Corps), Antimisiaris is currently one of the pilots of the highly modified Boeing 747SP that serves as the platform for the Stratospheric Observatory for Infrared Astronomy, or SOFIA, flying observatory. Then it was mothballed in the Nevada desert, where NASA found it. In other instances, visible light is concealed by clouds of gas and dust in space.

They operate at different infrared wavelengths. Our open plane galley includes a microwave oven, refrigerator, and a table overflowing with high energy snacks, jerky, and an avalanche of junk food. If you know your browser is up to date, you should check to ensure that The crew puts on their sweaters and jackets.

With flaps fully deployed on approach, we touch down on time -- at 6:22 a.m. -- after 9 hours, 46 minutes aloft. NASA had told us proudly that, when SOFIA's telescope door opens at 35,000 feet, there would be no detectable buffeting inside the cabin.

It took 13 years to remodel the plane, install new equipment, put in retractable fuselage doors and to test it.Finally, on November 30, 2010, SOFIA embarked on its first full science research flight.Even with the backing of deep-pocketed partners, the SOFIA program was nearly canceled in 2006 before it ever flew and nearly canceled in 2013 due to budget cuts. There's a reason why the telescope resides on the left side of the aircraft.

Fewer than five examples remain airworthy today.It's essentially a 747-200 model, except it's 47 feet shorter. The program costs $85 million per year in US funding and $20 million from DLR. To get the best experience possible, please download a compatible browser. SOFIA is a joint international effort by NASA and DLR, the German Aerospace Center. We wound our way up the 1970s vintage spiral 747 staircase to discover the most intimate of intimate upper decks: A shortened upper cabin consisting of Lufthansa Business class seats.This space army definitely travels on its stomach.

"Up to moderate turbulence, the telescope can still make reliable observations," says SOFIA pilot Capt. The only thing pumping more than the four mighty Pratt & Whitney engines are our hearts, with adrenaline.

javascript is enabled. Right on schedule.Because it's not being used as a passenger jet, the plane's low weight lets it thrust into the cool desert air in less then 40 seconds.