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United States Air ForceLaunch SuccessfulAstrophysicsDelta II
Launched 2004-04-20 16:57:24 UTCSpace Launch Complex 2W, Vandenberg SFB, CA, USA
Success
Reached Low Earth Orbit
Worldwide
14th
orbital launch attempt in 2004
United States Air Force
3rd
launch this year
Space Launch Complex 2W
1st
launch from this pad this year
Pad turnaround
463 d 16 h
since the pad's previous launch
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.
Launch Provider
Government · United States of America · Founded 1947 · Commander-in-Chief President of the US
The United States Air Force (USAF) is the air service branch of the United States Armed Forces, and is one of the eight uniformed services of the United States. Originally created on 1 August 1907, as a part of the United States Army Signal Corps, the USAF was established as a separate branch of the United States Armed Forces in 1947 with the enactment of the National Security Act of 1947.
Launches
1,078
Successful
972
90%
Upcoming
0
scheduled
Height
38.7m
Diameter
2.4m
To low Earth orbit
5,959kg
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