Probe spies landers on Red Planet

The Spirit rover is currently in Mars' Columbia Hills Enlarge Image

New images have been released of past and present US landing craft on the surface of Mars taken by Nasa's Mars Reconnaissance Orbiter (MRO) probe.

The Spirit rover, which touched down in 2004, as well as both Viking landers, sent to explore the Red Planet in the 1970s, can be seen in the new images.

Besides providing new portraits of the robot emissaries, the images offer new information on the surrounding terrain.

MRO entered into orbit around the Red Planet earlier this year.

Dramatic photo

"We know these sites well at ground level through the eyes of the cameras on Spirit and the Viking landers," said Dr Alfred McEwen from the University of Arizona, who is principal investigator for the High Resolution Imaging Science Experiment (Hi-Rise) camera on MRO.

Viking 1 returned the first view from the Martian surface Enlarge Image

He added the pictures would help scientists interpret orbital images from other parts of Mars never seen from ground level.

Hi-Rise's view of Spirit amid Mars' "Columbia Hills" is quickly being put to use by scientists and engineers who plan the rover's daily activities.

It complements a dramatic photograph released in September of Nasa's Opportunity rover at the edge of a Martian crater.

First view

The view of Viking Lander 1 reveals the spacecraft's back shell about 260m (850ft) away and the heat shield at nearly four times that distance.

Viking lander 2 has never been seen in images from space Enlarge Image

Viking 1 returned the first view from the surface of Mars and kept operating for more than six years after its touch down on July 20, 1976.

"The biggest surprise is that you can still see what appears to be the parachute after 30 years," said Dr Tim Parker, of Nasa's Jet Propulsion Laboratory in California.

His calculations helped determine where to point the orbital camera for seeing the Viking landers.

Viking Lander 2, unlike Spirit and Viking Lander 1, had not been detected previously in images from Nasa's Mars Global Surveyor spacecraft.

'Lost landers'

This month, the team plans to take images of another US lander; Mars Pathfinder, which reached Mars in July 1997 and carried out science activities on the surface.

Britain's Beagle 2 did not call Earth in December 2003

They also aim to identify several "lost" landers; Britain's Beagle 2, Nasa's Mars Polar Lander, and the Soviet craft Mars 2, Mars 3 and Mars 6.

Dr Nathan Bridges, a Hi-Rise team member and scientist at JPL said these craft would be more difficult to find.

"We don't know their precise locations. This is also the case with the Viking landers, but we had a better idea where they were," he told BBC News.

The south polar layered deposits, where Mars Polar Lander was to have touched down in 1999, are currently in darkness. So mission scientists have to wait several months before Mars' position changes relative to the Sun.

Soviet landers Mars 2 and 3 were identical spacecraft

"With Beagle 2, we want to try for it. We only have a rough idea where it is located. Whether we are able to get it is problematical.

"Even if it is in the image, it will take some searching. And, of course, it is somewhat smaller than all the other landers," said Dr Bridges.

Dr Bridges said the chances of finding the Soviet landers were relatively good because of their large sizes.

The images from Hi-Rise are so sharp, scientists think they will be able to identify individual rocks that appear in famous photographs by the Viking landers. These include "Ankylosaurus," a rough rock about a metre (3ft) long near Viking Lander 2, and the larger rock nicknamed "Big Joe" near Viking Lander 1.

Mars Reconnaissance Orbiter reached the Red Planet in March this year.