NASA delays robot Mars life-search mission

By Will Dunham

WASHINGTON (Reuters) - NASA said on Thursday that it will postpone by two years the planned launch of a major mission to study whether Mars was ever capable of harbouring life, citing development and testing delays.

NASA administrator Michael Griffin said the Mars Science Laboratory mission must be pushed back from next year in part because of problems with motors on the six-wheeled rover designed to operate on the unforgiving surface of the Red Planet.

The delay of the planned October 2009 launch to autumn 2011 is expected to add about $400 million (273.4 million pounds) to the program's cost, now estimated at $2.2 billion to $2.3 billion, said Doug McCuistion, director of the NASA Mars exploration program.

The mission is designed to assess whether the Martian environment is or ever was able to support microbial life. It is the latest in the exploration of Earth's neighbour, which scientists believe had abundant liquid water on the surface in the past and may have been home to some type of life forms.

"I have full confidence in the JPL team (NASA's Jet Propulsion Laboratory in Pasadena, California) to be able to work through the difficulties, but we've determined that trying for '09 would require us to assume too much risk -- more than I think is appropriate for a flagship mission like Mars Science Laboratory," Griffin told a news conference.

"A mission like this ranks just behind a manned mission in importance," Griffin said.

Griffin said if the U.S. space agency could delay launch by a few months, that probably would take care of the problem. "But launch opportunities for Mars don't allow that. They come every 26 months. So we either go in 2009 or 2011," he said.

The positions of Earth and Mars relative to one another as they orbit the sun are favourable for interplanetary flights for only a few weeks every two years, officials said.