SALT LAKE CITY — NASA has awarded defense contractor Alliant Techsystems Inc. $1.8 billion to develop a motor for the Orion capsule, which will replace the space shuttle and be able to reach the moon and Mars, the company said.

The first-stage propulsion system will lift astronauts solely with solid fuel instead of a combination of solid and more volatile liquid fuel, the company said in a news release Friday.

The development contract doesn't guarantee Alliant will produce the next generation of first-stage boosters, but Alliant's Thiokol plant in northern Utah has made shuttle boosters from the start of the space shuttle program.

The company, also known as ATK, said the contract runs through 2012 and calls for it to deliver five new motors and other equipment for test flights.

Orion will be the Apollo capsule-like replacement for the 26-year-old space shuttle fleet that is supposed to retire in 2010, after completion of the international space station.