Names | EPE-A Energetic Particles Explorer-A Explorer XII NASA S-3 |
---|---|
Mission type | Space physics |
Operator | NASA |
Harvard designation | 1961 Upsilon 1 |
COSPAR ID | 1961-020A |
SATCAT no. | 00170 |
Mission duration | 365 days (planned) 112 days (achieved) |
Spacecraft properties | |
Spacecraft | Explorer XII |
Spacecraft type | Energetic Particles Explorer |
Bus | S-3 |
Manufacturer | Goddard Space Flight Center |
Launch mass | 37.6 kg (83 lb) |
Power | 4 deployable solar arrays and batteries |
Start of mission | |
Launch date | 16 August 1961, 03:21:25 GMT |
Rocket | Thor-Delta A (Thor 312 / Delta 006) |
Launch site | Cape Canaveral, LC-17B |
Contractor | Douglas Aircraft Company |
Entered service | 16 August 1961 |
End of mission | |
Last contact | 6 December 1961 |
Decay date | 1 September 1963 |
Orbital parameters | |
Reference system | Geocentric orbit[1] |
Regime | Highly elliptical orbit |
Perigee altitude | 790 km (490 mi) |
Apogee altitude | 77,620 km (48,230 mi) |
Inclination | 33.40° |
Period | 1587.00 minutes |
Instruments | |
Charged particles Cosmic-Ray Experiment Electrostatic Analyzer of Solar Plasma Fluxgate Magnetometers Proton-Electron Scintillation Detector Solar Cell Damage Experiment | |
Explorer Program |
Explorer 12, also called EPE-A or Energetic Particles Explorer-A and as S3), was a NASA satellite built to measure the solar wind, cosmic rays, and the Earth's magnetic field. It was the first of the S-3 series of spacecraft, which also included Explorer 12, 14, 15, and 26.[2] It was launched on 16 August 1961, aboard a Thor-Delta launch vehicle.[1] It ceased transmitting on 6 December 1961 due to power failure.[2]