US: The problems with the Discovery flight are reigniting the debate about the wisdom of human space travel, writes Victoria Griffiths in Boston
US celebrations over the safe return of the space shuttle Discovery for a smooth landing in the Californian desert yesterday may be short-lived.
"We're happy to be back and we congratulate the whole team," said Eileen Collins, Discovery's flight commander and the first woman to perform such a role.
When Discovery entered space two weeks ago in what seemed to be a picture-perfect lift-off, it was hailed as a triumphant comeback of the US manned space programme.
Yet it quickly became clear that the launch had not gone as smoothly as at first appeared, causing Nasa to suspend future flights indefinitely.
The concerns are reigniting a debate about the wisdom of human space travel. "This was just short of a disaster for the future of manned space flights," said Robert Park, professor of physics at the University of Maryland and a spokesman for the American Physical Society.
"It's clear they have to kill the shuttle, and pretty quick."
Many experts, including Prof Park, favour more robot missions, such as the one taking off from Florida today to explore water sources on Mars.
Because the shuttle is the only US craft capable of transporting cargo and crew back and forth from the International Space Station, it seems unlikely Nasa will scrap it entirely.
"It's conceivable that the shuttle could be judged too risky to fly, but I don't think that will happen," said John Logsdon, director of the Space Policy Institute at George Washington University.
"The important decision now is to what level we want to complete the ISS and how many trips we need to make to do that."
A less ambitious International Space Station construction programme could mean a sharp cut in the scheduled number of flights: five a year until 2010. Additional safety measures are also likely, which would add to the $1.4 billion Nasa has spent on reducing shuttle flight risk.
In question is congressional funding for the ISS and the White House's ambitious goal of sending men to the moon, then Mars.
"Ultimately, I know we must retire the shuttle and replace it with a new vehicle," said congressman Ken Calvert yesterday.
Designs for the Crew Exploration Vehicle are to be published this month, but the craft would not be ready before 2011.
Nasa attributed Discovery's safe return partly to luck. Falling foam from the external engine at launch narrowly missed the craft; the same problem doomed the Columbia in 2002.
Later, unrelated damage was discovered to the "gap filler" material on the orbiter's belly, prompting the first in-flight repair.
Also for the first time, Nasa recorded the lift-off with hundreds of cameras and when the orbiter docked with the ISS, astronauts took photographs of the underside of the Discovery, discovering minor damage.
The mission however marks a new awareness of issues that might endanger the craft, intensifying fears that the shuttle may be too dangerous to continue flying. - (Financial Times service)