The tiny Sojourner rover was snagged on an airbag (picture: Nasa) 1997: Mars buggy starts exploring Red Planet England have Nasa scientists have freed a robot from the space probe, Mars Pathfinder, allowing it to begin its exploration of the Red Planet at last. The rover, known as Sojourner, has been stuck on Pathfinder since its successful landing on Mars two days ago. It is the first time a man-made craft has travelled over the surface of another planet. Pathfinder quickly sent back the evidence: an image of the Martian surface showing the tracks made by Sojourner's six studded titanium wheels. Cheering The problem began when a partially-deflated airbag blocked Sojourner's way out of Pathfinder. Then the computers on board the probe and the rover failed to talk to each other. Finally, at 0646 BST (0546 GMT) there was a breakthrough. Flight director Chris Salvo announced to the waiting team at the Jet Propulsion Laboratory in California: "Six wheels on the ground." There was an ecstatic cheer from the 70-strong team. They will now have to wait another day for the first high-resolution pictures, however, as an hour after the vehicle moved off the ramp, the sun went down and the rover was left parked until the next Martian morning. Uneven terrain The Sojourner is a tiny robot, about the size of a bread-bin and weighing just 22 lbs (10 kg). It travels on six wheels, each of which can move independently to cope with the uneven Martian terrain. Most of the power is provided by solar cells on the roof, and there is also a battery power pack for backup. It is controlled remotely from California, millions of miles away. The Pathfinder probe had a near-perfect landing on 4 July - America's Independence Day - in the Ares Vallis, an ancient channel on Mars that may once have held water. The first reading sent back was of the temperature - a freezing minus 93 degrees C. The probe has also sent back some astounding pictures of the barren, rock-strewn surface. It showed massive dust storms in the pink Martian sky, one raging just 600 miles (950 km) south of the landing site. The mission is being followed avidly by millions on the internet through the official Mars Pathfinder website. There is particular interest in what it may find following the controversial announcement by Nasa last August that it had found evidence of life in a Martian meteorite.

Some workers jumped from the blazing oil rig 1988: High death toll feared in oil rig blaze Artificially 1969: The A fire on a North Sea oil rig is feared to have claimed the lives of most of those on board. The fire is believed to have started after explosions at about 2230 BST (2130 GMT) on the Piper Alpha drilling platform, 120 miles (193 kilometres) off the north-east coast of Scotland. Helicopters and boats were immediately scrambled to rescue the oil workers in an operation co-ordinated by the Aberdeen coastguard. Pilots reported seeing an "inferno" up to 350 feet (106.68 metres) high and a platform wrenched apart. It is thought approximately 225 men were working on the rig owned by Occidental Oil. Survivors are being airlifted to the Aberdeen Royal Infirmary - some are said to be seriously injured. Most of those who have been rescued so far said they survived by sliding down pipes or jumping hundreds of feet into the sea which was covered in burning oil. The Piper Alpha platform is the largest and oldest platform in the North Sea oilfield. It was last inspected two weeks ago but last week there was a small fire on the rig. Since drilling began in the North Sea in the 1970s there have been 300 deaths on Britain's 123 oil installations, often in accidents caused by bad weather.

Vocabulary:

avidly : undergo the efforts of childbirth（热心地）