"GP-B confirmed two of the most profound predictions of Einstein's universe, having far-reaching implications across astrophysics research.
GP-B is one of the longest running projects in NASA history, with agency involvement starting in the fall of 1963.
At least for frame dragging, GP-B's expected accuracy is not really a coup, says Nordtvedt.
Francis Everitt, who has led the GP-B project for decades.
"GP-B will provide a direct measurement," noted the review panel that last April endorsed the mission.
Indeed, much of the long development of GP-B has gone to creating the gyroscopes and other technological wonders essential to making such fine measurements.
But convincing gravity specialists of the result's validity would be difficult, unless the GP-B team could rule out all sources of instrument error, says gravitation theorist M.
GP-B actually stands a better chance of finding a flaw in Einstein's prediction of geodetic precession.
"Some people view this part of GP-B as the more important test," Will says.
GRAND FINALE For GP-B to have reached the launch site is nothing short of a miracle to many people.
Since then, GP-B has missed four rescheduled launch dates, in part because of technical problems.
GP-B is expected to measure gamma 2.5 to 6 times as precisely.