My Night in the Stratosphere

What's it like to fly on a repurposed Boeing 747 with a huge rectangular hole in its side — and a state-of-the-art telescope peering out through it?

After three years of trying — six attempts in all — I finally got my chance to fly aboard the one-of-a-kind Stratospheric Observatory for Infrared Astronomy. SOFIA is a repurposed Boeing 747SP aircraft that's been modified to observe while flying at altitudes of 39,000 feet (12 km) and above. The business end is a compact, 2.5-meter telescope that peers out into the universe through a hole in the fuselage. It's a big hole, 18 feet long and 13½ high (5.5 by 4.1 m), that gets opened once the plane reaches 30,000 feet.

As detailed in Sky & Telescope's May issue, I flew on SOFIA to find out what kinds of astronomy can be done from the stratosphere. "Plenty," it turns out, and there's a long queue of astronomers waiting to use it. Most have been waiting a long time: the project began in 1997 and took 14 years and $1.1 billion to become fully operational. NASA and the German Aerospace Center (DLR) paid for it, and staff from Universities Space Research Association manage day-to-day operations.

Here are some behind-the-scenes snapshots of what it takes to get SOFIA airborne and its telescope feasting on starlight:

SOFIA gets ready to fly

SOFIA is stored and maintained at NASA's Dryden Aircraft Operations Facility in Palmdale, California. The arrow points to the giant door (slight bulge) that opens at altitude to expose the telescope.
S&T: J. Kelly Beatty

SOFIA preflight briefing

You can't just hop aboard. Passengers are required to pass an emergency-procedures class and to attend the preflight briefing.
S&T: J. Kelly Beatty

Kelly Beatty and Franck Marchis

Here I am with astronomer Franck Marchis, who plans to study the asteroid 2 Pallas on tonight's flight. My blue flight suit is made of Nomex, which is fire resistant. (Franck's T-shirt probably isn't!).
S&T: J. Kelly Beatty

SOFIA's spartan interior

It's definitely a no-frills flight. Many of the interior panels have been removed to permit access to cabling.)
S&T: J. Kelly Beatty

Brainstorming the flight plan

A cockpit glitch caused a 2-hours departure delay, and the flight team huddles to decide which observations won't get made. A typical flight all-night flight lasts 7 to 9 hours.
S&T: J. Kelly Beatty

SOFIA's interior

Everyone on the flight team has assigned stations. In fact, there's even a console for journalists and educators who come along.
S&T: J. Kelly Beatty

Kelly Beatty aboard SOFIA

During flight, the interior of SOFIA is very noisy. We all wear these military-grade "cans" — to deaden the loud drone and to communicate with each other.
S&T: J. Kelly Beatty