This article originally published in
Air and Space Magazine

GP-B began as a conversation in the late 1950s between three Stanford scientists: Leonard Schiff, William Fairbank, and Robert Cannon. "The original idea was Leonard’s," says Cannon, the only on of the three still alive. "He thought it was only a gedanken experiment-something you think through but never physically do. Fairbank’s contribution was to suggest we do this at zero degrees Kelvin, where everything is supposed to be perfect. Mine was to say we should go into orbit, where we could probably get the gyros’ weight down to about a millionth of their Earth weight."

Francis Everitt arrived at Stanford in 1962 as Fairbank’s protégé. Over the next five years a working model of the experiment began to emerge, but the problems seemed insurmountable. How could one stabilize an extremely sensitive gyroscope in an orbiting satellite, then keep it near absolute zero for the year or more the experiment would take? How could it possibly be kept free of disturbing outside influences during that time? And assuming all that could be done, how could one ultimately measure submicroscopic changes in the direction of its spin? Everitt recalls the reaction of one contractor NASA hired to check out the project’s feasibility: "These guys have got to be kidding."