1 Lynx

Type: Self-launched space plane

Who: XCOR Aerospace

Launching: 2014

Destination: Suborbital

The Odds: Good

Space is defined by a somewhat arbitrary number—climb above an altitude of 62 miles, the so-called Kármán Line, and an aircraft becomes a spacecraft. There the atmosphere is so thin that, for most scientific purposes, it's a vacuum. Because a so-called suborbital space flight to this altitude requires much less energy than an orbital launch—about one twenty-fifth as much—many private space companies are devising ways to get science experiments and wealthy tourists there. XCOR Aerospace of Mojave, Calif., believes it can offer the cheapest trip. It is already selling $95,000 tickets on a 30-foot space plane called the Lynx. "You're sitting in the cockpit," says XCOR chief operating officer Andrew Nelson, turning the spacecraft's small size and two-passenger maximum into selling points. "It's going to be a real astronaut experience." Unlike capsules and other space planes, the Lynx does not need to ride another rocket to get into space. Instead, the Lynx will fire its four custom-made kerosene and liquid-oxygen rocket engines to take off horizontally from a runway, as a plane does, and then climb steeply on its way to space. The first test flight may take place within months.

HOW IT WORKS

Takeoff: The space plane speeds along a runway under the power of four rocket engines.

Ascent: The Lynx reaches Mach 2.9 as it speeds straight upward.

Apogee: The engines cut out about 3 minutes after takeoff. The craft follows a parabolic trajectory in suborbital space.

Reentry: Thermal insulation on the nose and leading edges of the wings protect the craft from the heat of reentry.

Landing: The space plane sheds speed by circling in a downward corkscrew. The wing area is sized for landing at moderate speeds, near 110 knots—a little slower than that of an airliner during a landing.

Fly Again: Lynx's creators say the space plane will be able to make four flights a day.