Posted on 23-1-2003

Nasa's Mars rover stops working

Nasa's six-wheeled rover robot Spirit has stopped transmitting useful data from its mission on Mars for more than 24 hours, its managers said today, describing the problem as "extremely serious".
The Spirit team at the US space agency last heard from their rover early yesterday on its 18th day on the red planet. Since then, it has only sporadically returned random, meaningless radio noise.

It is an unexpected setback. In contrast to the British Beagle 2 mission, which has apparently ended in failure after scientists failed to make contact after it was due to reach the Mars surface on Christmas Day, the US mission has been going well, with Spirit sending back impressive pictures.

At first, Nasa scientists believed weather problems on Earth might be causing the glitch but now they fear the rover is experiencing hardware or software problems.

Nasa can fix software from Earth, beaming information across more than 100 million miles of space. But if the problem lies with the rover's hardware, the situation would be far more grave. The project manager, Pete Theisinger, said: "This is a serious problem. This is an extremely serious anomaly."

Nasa last heard from Spirit as it prepared to continue its work examining its first rock, just a few metres from its lander. Since then, Spirit has transmitted just a few beeps to Earth in response to attempts to communicate with it. It also has skipped several scheduled communications opportunities, either directly with Earth or by way of two Nasa satellites in orbit around Mars.

Engineers at Nasa's jet propulsion laboratory are working to pinpoint the problem. "It's not clear there is one cause ... that would explain the observables we're seeing," deputy project manager Richard Cook said.

He said there were encouraging preliminary indications that its radio was still working and that it continued to generate power from the sun with its solar panels.

The robot had been scheduled today to grind away a tiny area of the weathered face of a sharply angled rock dubbed Adirondack. Examination of the rock beneath could offer clues to Mars' geologic past. But Spirit has remained immobile.

Yesterday Nasa scientists said a thunderstorm near a Deep Space Network radio antenna in Canberra, Australia disrupted controllers' efforts to initiate the drilling. But it has since discounted the weather as the source of the communications blackout.

Spirit is one half of a £444m mission. Its twin rover, Opportunity, is scheduled to land on Mars on Saturday.

Spirit landed on Mars on January 3 for a three-month mission to search Gusev Crater, a rock-strewn stretch of dusty, streaked soil that scientists believe may be the bed of an ancient lake. If Mars once had surface water, it had the potential to support life.