Nasa controllers on Sunday night set the countdown clock ticking to the first shuttle flight since the Columbia disaster.
Crew safety has become the priority of the national space agency in the two and a half years since seven astronauts were lost when Columbia blew apart during re-entry over Texas, and Nasa has spent $1,1-billion to ensure the rest of its ageing shuttle fleet can fly again.
When Discovery — at 21 the oldest of the three remaining orbiters — lifts off from the Kennedy Space Centre at 3.51pm local time on Wednesday, it will be the most closely watched space flight in history.
”This flight begins a new chapter in space exploration,” said Discovery commander Eileen Collins. ”We’re doing what we need to do as humans, and that’s to explore. By exploring, we continue to make this world a better place to live and we continue to grow as a human species.”
Collins and her six crew members arrived in Florida on Saturday, their flight from Johnson Space Centre in Houston brought forward a day to escape the worst effects of Hurricane Dennis, which was heading north and skirting the state’s west coast.
Nasa meteorologists had feared the hurricane might force a postponement of the launch but the storm’s north-westerly track steered it away from the Space Coast. Weather conditions on Wednesday, the opening of a 19-day window for the start of the 12-day mission, are expected to be favourable.
Getting Discovery to the launch pad for what is essentially a test flight has been hard for Nasa, which never completely recovered from the explosion that destroyed the shuttle Challenger and its crew of seven in 1986, less than a minute after its launch.
The agency’s managers were criticised by the Columbia accident investigation board (CAIB) for operating under a continuing ”culture of complacency”.
Safety concerns from ground crew were ignored, particularly about the fatal damage caused to Columbia’s wing by a block of insulating foam falling from a fuel tank after its lift-off in January 2003.
The external tank has been completely redesigned, but three of the investigating panel’s 15 recommendations for a safe return to flight have not been met, including finding a way of eliminating the risk from falling debris.
Even so, the Nasa administrator, Mike Griffin, said that Discovery was as safe as possible within the boundaries of human knowledge. ”If someone wants more, they are going to have to find smarter humans,” he said.
John Logsdon, director of the Space Policy Institute at George Washington University and a member of the CAIB, agreed.
”’Safe’ is an absolute term, and this will never be safe. It’s always going to be risky,” he said. ”But has Nasa got rid of as much risk as is possible? Given the fact that they can’t reinvent the vehicle, I think so. They have worked hard to address the problems we pointed out, the CAIB and others, and they have had some good people looking over their shoulder.”
Discovery will spend eight days docked alongside the International Space Station and the crew will also test safety procedures, including a space-walk for an experimental repair technique on the shuttle’s protective heat-resistant tiles.
Astronauts Soichi Naguchi, of Japan, and Steve Robinson will make a second space-walk to repair a damaged gyroscope that controls the Space Station’s movements in orbit.
Collins and Discovery pilot Jim Kelly, nicknamed ”Vegas” for his love of poker, will spend the final two days before the launch practising flight manoeuvres in a shuttle simulator.
”Getting this mission behind us is key to everything that follows,” Logsdon said. ”The shuttle is a short lifetime vehicle and retiring in five and a half years, but behind it is an ambitious, bold, long-range plan to return to the moon and on to Mars, and it’s going to be hard to do that if this mission doesn’t go well.” – Guardian Unlimited Â