An artist's concept of GP-B. Photo: Stanford

The Einstein Gravity Probe-B -- a spacecraft designed to test how the Earth's mass warps spacetime -- has suffered another serious set back. The NASA-Stanford University collaboration has recently admitted that it is set to pay a $70 million over-run cost, and possibly postponing the launch of the probe a further six months.

The Einstein probe is anticipated to provide new and stringent tests of some of the predictions of general relativity. In particular, the spacecraft is designed to test for frame dragging by the Earth as it rotates in space.

To test Einstein's abstract ideas, four ultra-sensitive gyroscopes have to be placed within a supercooled structure that resembles a thermos flask. But the Stanford team has experienced problems with positioning the gyroscopes properly. Added to this, are difficulties attending the cooling of the instrument. As the principal investigator Francis Everitt at Stanford University glumly conceded, "the situation is annoying, very embarrassing and very frustrating."

Though slated for launch in 1999, Everitt believes that there is still a 50:50 chance that it could be ready to head for space by the anticipated launch date of September 2001. But not everyone is as confident. The longer the overrun time, the more expensive the project becomes. This concerns NASA, as the extra money needed to rescue the Gravity B project invariably results in jeopardizing important ongoing projects, especially the anticipated 2003 Europa orbiter mission.