Masten Space Systems of Mojave, Calif., has been declared the first-place winner of NASA's Lunar Lander Challenge, sponsored by the Northrop Grumman Corp.

Second prize in the competition, part of NASA's Centennial Challenges program, was captured by Armadillo Aerospace of Rockwall, Tex. Masten will received $1 million for its achievement, while Armadillo Aerospace will be awarded $500,000.

The companies will be recognized Thursday during an award ceremony for successfully simulating landing a spacecraft on the moon and lifting off again. The ceremony for the competition, which was managed by the X-Prize Foundation, will be held at the Rayburn House Office Building in Washington.

The Lunar Lander Challenge involved building and flying a rocket-powered vehicle that simulates the flight of a vehicle on the moon, NASA said. The lander had to take off vertically and then travel horizontally, demonstrating both power and control before landing accurately at another spot. The same vehicle then had to take off again, travel horizontally back to its original takeoff point and land successfully, all within 2 hours and 15 minutes.

In addition the rocket's engine had to be started twice within a short time with no ground servicing other than refueling.

The average landing accuracy determined which teams would receive first and second place prizes. The Masten team achieved an average accuracy of 7.5 inches, while Armadillo Aerospace's average accuracy was 34 inches.