309 million miles from the nearest garage

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The Independent Online
You know how it is: you travel a long way, stop overnight, and then it's hell getting the car started in the morning, writes Charles Arthur. That was the story for scientists at the Jet Propulsion Laboratory in California yesterday - except that the car was 309 million miles away, parked on the Lander section of the Pathfinder spacecraft which came to rest on Mars on Friday night in the first contact from Earth for 21 years.

Early this morning they were trying to get the Sojourner, a six-wheeled, 22-pound, solar-powered rover, to drive off the Lander and on to the planet's surface. First of all it had been delayed because the airbags on the Lander failed to deflate fully after the bumpy landing, which bounced the Lander up to 15 feet into the air before coming to a stop. That problem appeared to be solved by moving one of the "petals" - the sides of the Lander that open - up and down to empty the airbag. Then they discovered that computers on the rover and the Lander were not communicating. To cheers in the control room, the vital link was restored late last night.

The plan now is that Sojourner - named after a black slavery abolitionist, Sojourner Truth - will be driven down the ramp by a Nasa scientist using a virtual reality headset and driving "glove" to steer the vehicle. There is an 11-minute time-lapse before signals reach the rover, but fortunately the most off-road vehicle in the solar system has a top speed of just a half-inch per second - a modest 0.02 mph.

Even if Sojourner can not be driven directly from Earth, it can be sent on a pre-programmed mission. But scientists are already delighted. Pathfinder has beamed back clear pictures showing a dry, dusty surface - looking as familiar as a desert, yet disturbingly alien for its lack of cactus, brush or blossom. The atmosphere has proved dustier than expected, creating a salmon-coloured sky. If the dust gets too thick, then solar- powered batteries on Pathfinder and Sojourner will run down sooner. Report, page 3; The UFO business, page 12