US: Nasa last night cleared the space shuttle Discovery for a return to earth next week after deciding that another risky spacewalk would not be needed to fix the last remaining safety concern.
Some engineers had feared that a section of ruptured insulating blanket beneath the shuttle's cabin window might require repairs similar to astronaut Steve Robinson's delicate DIY operation on Wednesday, in which he was dangled 224 miles above earth by his boots.
But after two days of wind tunnel testing and intense debate on the ground, the space agency announced yesterday that it did not believe the blanket would pose a danger to Discovery as it re-enters the earth's atmosphere.
Astronauts were told they could end their 13-day mission on Monday morning as planned.
The crew enjoyed a rest day yesterday, giving them the opportunity to reflect on the success of Mr Robinson's precision manoeuvres. "We were watching with anticipation and excitement. When Steve pulled out the gap filler I started clapping and we were cheering on the flight deck," said commander Eileen Collins.
Joined by International Space Station crew members Sergei Krikalev and John Phillips, the seven read a tribute to the 21 astronauts and cosmonauts killed in five American and Russian space tragedies since 1967, including the Challenger and Columbia shuttle disasters of 1986 and 2003.
"These are the men and women who have come before us, in courage, but who did not complete their journey of exploration," said Discovery's pilot, Jim Kelly.
Meanwhile, the crew yesterday reported widespread environmental destruction on earth and warned that greater care was needed to protect natural resources.
"Sometimes you can see how there is erosion, and you can see how there is deforestation. It's very widespread in some parts of the world," said Ms Collins in a conversation from space with Japanese officials in Tokyo, including prime minister Junichiro Koizumi.
"We would like to see, from the astronauts' point of view, people take good care of the earth and replace the resources that have been used," said Ms Collins, who was standing with Japanese astronaut Soichi Noguchi in front of a Japanese flag and holding a colourful fan. Ms Collins, flying her fourth shuttle mission, said the view from space made clear that earth's atmosphere must be protected.
"The atmosphere almost looks like an eggshell on an egg, it's so very thin," she said. "We know that we don't have much air, we need to protect what we have." - (Guardian service, Reuters)