NASA's Cost-Benefit Analysis Under Fire

Albert Einstein's (search) nearly century-old theory of relativity is a generally accepted fact. But in two weeks a team from Stanford University and NASA (search) will conduct a physics experiment in space to see if Einstein's theory, which explains gravity as a distortion in time and space created by massive objects such as planets and stars, was right.

"It's great to be beyond the point of building, to the point of actually launching," said Francis Everitt, a Stanford University professor and the lead investigator of Gravity Probe B (search).

Getting to this point hasn't been easy or cheap. Since its proposal more than 40 years ago, the satellite has been plagued by technical glitches and false starts at a price tag that already tops $700 million.

"Never have we spent so much to get so little information," said Edward Hudgins, author of "Space: The Free Market Frontier."

Critics don't dispute the impressive technology that has gone into Gravity Probe B. Four ping-pong ball gyroscopes will spend 16 months in orbit, spinning in a sealed vacuum. If Einstein's theory holds, the balls will shift in small, but measurable ways.

But some are wondering why relativity, which has been repeatedly proven on Earth, needs to be confirmed in space — on the public's dime.

Click here for a report by Fox News' Claudia Cowan.