NASA Spacecraft Lands on Mars

The Phoenix has landed on Mars -- much to the relief of worried flight controllers 170 million miles away at NASA's Jet Propulsion Lab in California, who were helpless to do anything if Phoenix ran into trouble.

It was a tense time while flight controllers waited for a signal from Phoenix. Radio signals even traveling at the speed of light take 15 minutes to get from Mars to Earth.

Phoenix survived a harrowing 12,700 mph descent to the icy north pole of the planet. The landing zone chosen for the probe was a small rocky area on the north pole with interesting polygonal shapes in the terrain that is tempting to scientists.

The goal of the trip is to try to determine whether conditions ever existed on Mars that could have supported life?

NASA's Phoenix Lander was launched last August, and traveled 422 million miles in nine months to get to Mars.

It is a $457 million robotic spacecraft equipped with a backhoe, cameras and a compact chemistry lab, which will attempt to find out if the cold, forbidding surface of Mars could once have been warm enough for microbial life to exist on the planet

The Phoenix landed in an area of Mars where water is believed to exist in the form of ice just below the surface.

This ice is probably spread fairly uniformly throughout the planet's northern plains, so the lander should be able to uncover ice wherever it lands on what is believed to be the remnant of an ancient northern sea.

The spacecraft-turned-science lab will use its mini backhoe to dig down to the icy layer around the landing site and scoop up samples of the soil to dump into its onboard chemistry lab.

The trip came at a high pricetag, but NASA officials believe that it could pay off with big benefits for life on Earth.

Peter Smith, the principal investigator for the Phoenix mission, says what they find on Mars could provide answers to problems on Earth such as climate change.

"Arctic regions on planets harbor organic materials that make up life and are preserved," he said. "We believe that perhaps a history of organic life exists, because it would have been brought in by asteroids and comets that we know hit Mars."