NASA picks Lockheed to build shuttle replacement

NASA picked Lockheed Martin on Thursday as the prime contractor to build the Orion spaceship, which will replace the aging shuttle fleet and take astronauts to the moon for the first time since 1972.

The contract's initial phase, valued at $3.9 billion, would get the U.S. space agency one ship made to carry crew and another for cargo; people are expected to fly on the new vessel by 2014. The first lunar voyage should happen by 2020.

"Space is no longer going to be a destination that we visit briefly," said Scott Horowitz, a former shuttle commander who now head's NASA effort to develop a new generation of spacecraft. Eventually, Horowitz said at a briefing, humans will stay at a lunar base for six months at a time.

The moon outpost is part of President George W. Bush's " Vision for Space Exploration," which aims to send people back to the moon for the first time since the last Apollo flight there in 1972, and eventually on to Mars.

"We're going to learn to live off the land like the pioneers did," Horowitz said. "In order to be able to go to Mars we have to learn a lot of lessons on the moon, because while you can get to the moon and back in a few days, Mars would be several years."

The Orion space vessel is a departure from the shuttle's winged design, and looks more like the capsules that carried Apollo astronauts to lunar orbit in the 1960s and 1970s. But while the appearance is similar to Apollo's, the Orion capsule's interior is about two and a half times bigger.

It will be able to carry four people to the moon, or six people to the International Space Station.

NASA reckons Orion will be 10 times safer than the shuttles because it has an escape rocket on top of the capsule that can quickly blast the crew away if launch problems develop.

The capsule rides at the top of a stacked rocket, instead of beside a big external fuel tank as the shuttle does. This is meant to minimize the chance that debris falling at launch would hit and damage the capsule.

Unlike the shuttle, which lands like an airplane, the Orion capsule would drift back to earth under a trio of parachutes, and NASA experts are still deciding whether to aim for land or water.

Falling debris has been a persistent problem for the shuttles, and was the cause of the 2003 shuttle Columbia accident. Foam insulation from the external tank damaged Columbia's wing on launch, opening a breach that let in superheated gases on re-entry, tearing the ship apart and killing all seven crew members.

The shuttle fleet is scheduled to retire in 2010 after completion of the now half-built International Space Station, and NASA chief Michael Griffin has acknowledged there will be a period when the United States will have no ship to take humans to space.

Lockheed, the top U.S. defence contractor, beat a team made up of Northrop Grumman and Boeing to win the Orion contract. Beyond the initial $3.9 billion, additional spacecraft purchases could add as much as $3.5 billion through September 2019 if all options are exercised.

Shuttle Atlantis is set to launch next Wednesday on a flight to the International Space Station next week to resume construction that halted after the Columbia accident.