Explorer 12

Explorer 12
Explorer 12 satellite
NamesEPE-A
Energetic Particles Explorer-A
Explorer XII
NASA S-3
Mission typeSpace physics
OperatorNASA
Harvard designation1961 Upsilon 1
COSPAR ID1961-020A Edit this at Wikidata
SATCAT no.00170
Mission duration365 days (planned)
112 days (achieved)
Spacecraft properties
SpacecraftExplorer XII
Spacecraft typeEnergetic Particles Explorer
BusS-3
ManufacturerGoddard Space Flight Center
Launch mass37.6 kg (83 lb)
Power4 deployable solar arrays and batteries
Start of mission
Launch date16 August 1961,
03:21:25 GMT
RocketThor-Delta A
(Thor 312 / Delta 006)
Launch siteCape Canaveral, LC-17B
ContractorDouglas Aircraft Company
Entered service16 August 1961
End of mission
Last contact6 December 1961
Decay date1 September 1963
Orbital parameters
Reference systemGeocentric orbit[1]
RegimeHighly elliptical orbit
Perigee altitude790 km (490 mi)
Apogee altitude77,620 km (48,230 mi)
Inclination33.40°
Period1587.00 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]

  1. ^ a b "Trajectory: Explorer 12 1961-020A". NASA. 28 October 2021. Retrieved 4 November 2021. Public Domain This article incorporates text from this source, which is in the public domain.
  2. ^ a b "Display: Explorer 12 1961-020A". NASA. 28 October 2021. Retrieved 4 November 2021. Public Domain This article incorporates text from this source, which is in the public domain.