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Gravity Probe A (GP-A) was a space-based experiment to test the equivalence principle, a feature of Einstein's theory of relativity. It was performed jointly by the Smithsonian Astrophysical Observatory and the National Aeronautics and Space Administration. The experiment sent a hydrogen maser—a highly accurate frequency standard—into space to measure…
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| Subject | Predicate | Object | Confidence | Src |
|---|---|---|---|---|
| Gravity Probe A | Apogee | 10,224 km (6,353 mi) | 1.00 | infobox |
| Gravity Probe A | COSPAR ID | GRAVR-A | 1.00 | infobox |
| Gravity Probe A | Deactivated | 18 June 1976 (1976-06-18) | 1.00 | infobox |
| Gravity Probe A | Disposal | Decommissioned | 1.00 | infobox |
| Gravity Probe A | Launch date | 18 June 1976 (1976-06-18) | 1.00 | infobox |
| Gravity Probe A | Launch mass | 60 kg (130 lb) | 1.00 | infobox |
| Gravity Probe A | Launch site | Wallops Flight Facility | 1.00 | infobox |
| Gravity Probe A | Mission duration | 1 h 51 m | 1.00 | infobox |
| Gravity Probe A | Mission type | Astrophysics | 1.00 | infobox |
| Gravity Probe A | Operator | NASA | 1.00 | infobox |
| Gravity Probe A | Power | 22 W | 1.00 | infobox |
| Gravity Probe A | Rocket | Scout | 1.00 | infobox |
| Gravity Probe A | Spacecraft | GP-A | 1.00 | infobox |
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