Gravity Probe B
Delta II
United States Air Force
Mission
Gravity Probe B
Type: Astrophysics
Gravity Probe B (GP-B) was a satellite-based experiment to test two unverified predictions of general relativity: the geodetic effect and frame-dragging. This was to be accomplished by measuring, very precisely, tiny changes in the direction of spin of four gyroscopes contained in an Earth-orbiting satellite at 650 km (400 mi) altitude, crossing directly over the poles.
Trajectory
The trajectory is unavailable. Check back for updates.
Location
Space Launch Complex 2W
Vandenberg SFB, CA, USA
714 rockets have launched from Vandenberg SFB, CA, USA.

Rocket
Delta II 7920-10C – United Launch Alliance
- Family: Delta
- Length: 38.7 m
- Diameter: 2.4 m
- Low Earth Orbit Capacity: 5959 kg
The Delta II 7920-10C was manufactured by United Launch Alliance with the first launch on . Delta II 7920-10C has 17 successful launches and 0 failed launches with a total of 17 launches. Delta II is an American space launch system developed by McDonnell Douglas, now part of the Delta rocket family operated by United Launch Alliance. With more than 150 missions and a nearly perfect track record, Delta II has established itself as one of the most successful orbital launch systems.
Agency
United States Air Force – USAF
- Type: Government
- Abbreviation: USAF
- Country: USA