Mars Phoenix Spacecraft Corrects Course

NASA's Mars-bound Phoenix lander completed its first and biggest course correction planned during the spacecraft's journey.

The second of the remaining five planned adjustments prior to landing is scheduled for mid-October.

"These first two together take out the bias intentionally put in at launch," said Brian Portock, Phoenix navigation team chief at NASA's Jet Propulsion Laboratory.

Phoenix blasted off Earth aboard a Delta 2 rocket on Aug. 4 and now careens through space at 74,200 mph (33,180 meters per second)-a speed necessary to cover the 422 millions miles (679 million kilometers) between Earth and Mars by May 25, 2008.

Following a difficult landing in the northern icy reaches of the red planet, Phoenix will unfurl a digging robotic arm to test the icy Martian soil for habitable conditions for microbial life.

So far, mission managers said, all is well.

"All the subsystems are functioning as expected with few deviations from predicted performance," said Joe Guinn, Phoenix mission system manager at JPL.

Over the next month, the $420 million spacecraft's support team will check its scientific instruments, radar and the communication system needed during and after the soil-sampler's landing. When it does land, Phoenix principal investigator Peter Smith said it will be a milestone in space exploration.

"We'll be discovering the truth about the icy regions on Mars," Smith said during a briefing shortly after Phoenix's early morning launch.