European Spacecraft Streaks Toward Mars

FRANKFURT, Germany (AP) – A European spacecraft streaked toward Mars on Monday – right on schedule – but mission controllers still rehearsed what could go wrong during the voyage to determine whether life ever existed on the Red Planet.

Mars Express’ mission would be jeopardized by any problems with its main engine, which must fire on Christmas Day to propel the spacecraft on its path around Mars. Once in orbit, the craft is supposed to send back 3-D overhead pictures of the planet surface and scan for underground water with a powerful radar.

The craft also will relay data from the Beagle 2 probe, which is due to land on the planet hours before the orbital launch.

Mars Express was launched June 2 atop a Russian Soyuz-Fregat rocket from the Baikonur cosmodrome in Kazakhstan. With the orbiter successfully on course, engineers are preparing the final commands for activation early Dec. 25 and simulating possible glitches.

One of those could involve Mars Express’ engine not firing. Controllers have practiced using a variety of different commands to start four thrusters on the craft.

“This has been rehearsed over the last months, twice a week. They know they can do it,” said Jocelyne Landeau, a spokeswoman for the European Space Agency at mission control in the western German city of Darmstadt.

If the thrusters fail, “then we’re in trouble,” she said.

Controllers also conduct daily drills for such emergencies as satellite link breakdowns and computer failures at mission control.

The Beagle 2 probe separated from the Mars Express craft Friday, bound for Mars. After parachuting through the atmosphere, the 143-pound probe will use inflatable gas bags to bounce to a soft landing, flip open and begin transmitting a preprogrammed “blip-blip-blip” signal telling controllers it has safely touched down.

That transmission has several chances of being picked up.

The first will be when NASA’s Mars Odyssey spacecraft passes overhead early Christmas Day.

“We are working very closely with our colleagues from NASA,” Landeau said. “They’ll get the data back to Earth, then pass it on to us and we will be able to tell if the landing has taken place.”

That same day, scientists at the Jodrell Bank Observatory in London will train a radio telescope on Mars in an attempt to pick up the signal. If the telescope fails to do so, Odyssey has a daily chance to pick up the signal until Mars Express makes its first contact with the probe, planned for Jan. 3.

The Beagle 2 probe, named for the ship that carried naturalist Charles Darwin on his voyage of discovery in the 1830s, will scratch Mars’ surface with a robotic arm to test for signs of organic matter. It is expected to transmit its first pictures from Mars to mission control early next month.

At about the same time, two NASA rovers will land on Mars to concentrate on geologic research and mapping.

Scientists believe Mars, which still has frozen water in its ice caps, once might have had liquid water and suitable conditions for life. Although those conditions were lost billions of years ago, it is believed that water may still exist as underground ice.

The European mission is the first search for signs of life on Mars since twin U.S. Viking landers probed the planet in 1976 but sent back inconclusive results.

Of 34 unmanned American, Soviet and Russian missions to Mars since 1960, two-thirds ended in failure. This month, Japan abandoned a mission to determine whether Mars has a magnetic field after failing to position its Nozomi probe on planetary orbit.

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On the Net:

Mars Express: www.esa.int/export/SPECIALS/Mars-Express/index.html

European Space Agency: www.esa.int/export/SPECIALS/Mars-Express/SEMTERWLDMD-0.html

Beagle 2: www.beagle2.com