A Delay for the Mars Probe

Having already waited 1,000 days to see the launch of the Mars Climate Orbiter, NASA project scientists will have to wait a few days more. The agency delayed the planned Thursday blastoff of the unmanned spacecraft to resolve a computer software problem that could affect power on the orbiter. "It's a little disappointing," said project manager John McNamee.

That the glitch is merely disappointing is significant, says TIME science writer Jeffrey Kluger. "One of the nice things about unmanned space missions is that they are economical," he says. "This means that when a glitch occurs on a project such as this one, it's jeopardizing a $200 million mission and not a $100 billion mission, as in the case of the manned space station project." As if to underline Kluger's point, two shuttle astronauts risked a space walk Wednesday to continue building the space station -- and, time permitting, to fix a stuck antenna.