[新闻][ 美国福克斯新闻网消息]火星快车进入环绕火星轨道。（英文）

Mars Express Orbits Red Planet

Thursday, December 25, 2003

DARMSTADT, Germany — Europe's Mars Express (search) went into orbit around the Red Planet (search) early Thursday, the mission's flight director said, and controllers' first attempt to find out if the craft's companion had landed safely on the Red Planet was unsuccessful.

 

Officials had hoped that NASA's (search) Mars Odyssey orbiter would pick up the signal from the Beagle 2 lander, which had earlier been set on its descent into the Mars atmosphere.

"We have had the information from Odyssey and it does not contain any data from Beagle," said Peter Barratt, a spokesman for the Beagle 2 mission in London. However, he added, "we are quite confident" that the landing will still be confirmed.

Controllers had been encouraged earlier because they received a signal from a small antenna aboard the lander's companion craft, the Mars Express as it emerged from behind Mars on schedule at 5:11 a.m. on Christmas Day, orbiting the planet. Flight director Michael McKay cautioned that the signal did not reveal if the spacecraft was working.

Mars Express reappeared following a maneuver in which it fired its engine to slow it enough for Mars' gravity to pull it into orbit. The craft will relay data from the Beagle 2 lander if it starts transmitting from the planet's surface.

The signal "was the first good indication that the burn went well," McKay said.

Confirmation that the maneuver was successful was expected in another few hours as controllers rotated the main antenna on Mars Express, which was reversed for the orbit maneuver, to face Earth.

Mars Express turned Beagle loose six days ago. Working in tandem, the lander and orbiter are meant to look for signs of past or present life on Mars.

The lander was scheduled to enter the upper Martian atmosphere at 3:45 a.m. (9:45 p.m. Wednesday EST). Now that the Odyssey failed to make contact, Britain's Jodrell Bank Observatory will try to pick up the lander's call signal at 5:45 p.m. EST on Christmas Day.

Parachutes and gas bags were to cushion the Beagle's impact after its fiery 7-minute descent through the Martian atmosphere. The 143-pound lander, shaped like an oversized wok, must open its solar panels and charge its batteries using the sun's energy before it can communicate -- sending a call signal composed by British band Blur.

Since separation, the British-built Beagle has neither received commands nor sent back data to mission control, a cluster of buildings surrounded by snow-dusted woods at the edge of Darmstadt in western Germany,

Mars Express won't be able to make contact with Beagle until Jan. 3 because its initial orbit is too high and will have to be adjusted.

Beagle, named for the ship that carried naturalist Charles Darwin on his voyage of discovery in the 1830s, is equipped with a robotic arm to sample surface rock and soil.

Mars Express is expected to orbit overheard for at least a Martian year, or 687 Earth days, probing as deep as 2.5 miles below the surface with a powerful radar to look for underground water. It will also map the surface with a high-resolution stereo camera.

Mars' surface is dry and cold, with ice caps of frozen carbon dioxide, or dry ice. Scientists believe that billions of years ago the planet may have been warmer and had enough liquid surface water to support life, which might have survived in cavities underground.

The planet's surface has features that some think could be dry riverbeds and ancient coastlines.

But getting a working spacecraft to Mars has proven frustratingly difficult. Of 34 unmanned American, Soviet and Russian missions to Mars since 1960, two-thirds have ended in failure.

The United States successfully landed two Viking craft in 1976 and Mars Pathfinder in 1997, but two years later lost the Mars Polar Lander during descent. Japan this month abandoned a Mars mission after failing to position the Nozomi probe on planetary orbit.

NASA's Spirit, one of two identical robot explorers, is expected to land Jan. 3. Its sibling, Opportunity, is scheduled to settle on the opposite side of the planet Jan. 24.

If all goes well, Beagle is expected to transmit its first pictures from Mars as early as Dec. 29-Dec. 31. The first radar pictures from Mars Express are expected in the spring.