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 Pioneer 3 being inspected before shipping to Cape Canaveral | |
| Mission type | Lunar flyby |
|---|---|
| Operator | NASA \ ABMA |
| Harvard designation | 1958 Theta 1[a] |
| COSPAR ID | 1958-008A |
| SATCAT no. | 111[a] |
| Mission duration | 1 day, 14 hours and 6 minutes |
| Apogee | 102,360 kilometers (63,600 mi) |
| Spacecraft properties | |
| Manufacturer | Jet Propulsion Laboratory |
| Launch mass | 5.87 kilograms (12.9 lb) |
| Start of mission | |
| Launch date | 6 December 1958, 05:45:12 GMT[1] |
| Rocket | Juno II |
| Launch site | Cape Canaveral, LC-5 |
| End of mission | |
| Decay date | 7 December 1958, 19:51 GMT |
Pioneer 3 was a spin-stabilized spacecraft launched at 05:45:12 GMT[1] on 6 December 1958 by the U.S. Army Ballistic Missile Agency in conjunction with NASA, using a Juno II rocket. This spacecraft was intended as a lunar probe, but failed to go past the Moon and into a heliocentric orbit as planned. It did however reach an altitude of 102,360 km before falling back to Earth. The revised spacecraft objectives were to measure radiation in the outer Van Allen radiation belt using two Geiger-Müller tubes and to test the trigger mechanism for a lunar photographic experiment.
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