Mars Lander frees its robotic arm – ready for initial tests

Happy NASA mission scientists said Thursday that the Phoenix Mars lander had successfully lifted its robotic arm, after freeing itself from a protective sheaf that did not fully unwrap after landing. ''All of the joints are healthy, and we're raring to go,'' Matthew L Robinson, the lead engineer for the mission's robotic arm flight software, said at a news conference.

The Phoenix's primary mission is to dig below the surface and scoop up ice thought to exist there in an attempt to discover signs that this region might have been warm and wet in the past and supported some kind of life.

The robotic arm will be put through its motions for a few days, before it attempts to scoop up Martian soil, along with ice, sometime next week.

NASA mission controllers also received new images that completed a 360-degree panorama of the Martian northern plains surrounding the Lander. According to Peter H Smith of the University of Arizona, the mission's principal investigator, the panorama revealed a ''hummocky terrain'' - flat land with bumps and troughs, apparently caused by the expansion and contraction of sub-surface ice.

The few rocks scattered around are small -  about five inches in diameter, with some as wide as eight inches - and mostly flat , Dr. Smith said. The rocks appear brighter than the soil.