Minuteman II Launched from Vandenberg

The U.S. military launched an intercontinental ballistic missile Tuesday night in an exercise to determine how well a new sea-based radar platform located near Alaska in the Pacific Ocean can track its course.

The Minuteman 2 missile lifted off from a silo on the northern part of the Vandenberg Air Force Base in Central California at 9:27 p.m. Its trajectory was tracked by sensors on a floating radar platform designed to distinguish dangerous warheads from decoy missiles.

The first launch countdown was scrapped because of technical difficulties, but the clocks were reset and the second try turned out to be a success.

"This was another safe and successful launch for the 30th Space Wing, the Air Force and the Department of Defense," said Col. Teresa Djuric, the spacelift commander.

Tuesday's test did not involve an interception. The Missile Defense Agency plans two intercept tests later this year - one in the spring and another in the fall to further test the performance of the mobile radar platform, which looks like a massive oil rig.

The 280-foot tall Sea-Based X-band Radar, developed by Raytheon Co., is so powerful it can identify baseball-sized objects from thousands of miles away.

The $815 million radar is mounted on a self-propelled, semi submersible platform that can sail to any location where the military needs to track missiles.

Vandenberg's next launch will be of a ground-based interceptor to try and stop a mock warhead launched from Alaska.

That launch date has yet to be announced. However it is planned for early spring