Explorer S-46 (satellite)

Explorer S-46
Prototype satellite payload of the Explorer S-46 satellite (Gift of James A. Van Allen and the University of Iowa) [1]
NamesNASA S-46
Mission typeEarth science
OperatorNASA / JPL
COSPAR IDEXS-46
Mission durationFailed to orbit
Spacecraft properties
SpacecraftExplorer S-46
Spacecraft typeScience Explorer
BusS-46
ManufacturerJet Propulsion Laboratory
Launch mass41 kg (90 lb)
Dimensions76 × 76 cm (30 × 30 in)
Power100 watts
Start of mission
Launch date23 March 1960, 13:35:11 GMT
RocketJuno II (AM-19C)
Launch siteCape Canaveral, LC-26B
ContractorArmy Ballistic Missile Agency
End of mission
DestroyedFailed to orbit
Orbital parameters
Reference systemGeocentric orbit (planned)
RegimeMedium Earth orbit
Perigee altitude573 km (356 mi)
Apogee altitude1,073 km (667 mi)
Inclination50.27°
Instruments
Cadmium sulfide (CdS) Proton Detector
Cadmium sulfide (CdS) Particle Detector
Electron Spectrometer
High Energy Geiger–Müller Tube
Medium Energy Geiger–Müller Tube
Explorer program
 

Explorer S-46 was a NASA satellite with a mass of 41 kg (90 lb). It was the last of the original series of Explorer satellites built, designed, and operated by the Jet Propulsion Laboratory and Army Ballistic Missile Agency (ABMA).[2]

Mission[edit]

Its mission was to analyze electron and proton radiation energies in a highly elliptical orbit.[2]

Spacecraft[edit]

Explorer S-46 was a joint ABMA / NASA-JPL mission. The payload detector experiments were developed by the State University of Iowa. The detector assembly comprised five instruments: a Cadmium sulfide (CdS) broom low-energy proton detector, a Cadmium sulfide (CdS) low-energy particle detector; an electron spectrometer; a Geiger-Müller high-energy particle counter; and a Geiger-Müller medium energy particle counter. These were housed in the front of the Sergeant rocket engine that comprised the fourth (upper-stage) of the Juno II launch vehicle.[2]

Payload experiments[edit]

  • Cadmium sulfide (CdS) Proton Detector
  • Cadmium sulfide (CdS) Particle Detector
  • Electron Spectrometer
  • High Energy Geiger–Müller Tube
  • Medium Energy Geiger-Müller Tube

Juno II[edit]

The four-stage Juno II launch vehicle used a Jupiter missile as the first stage. The second stage was assembled as a circumferential "tub" of 11 scaled-down Sergeant rocket engines (solid propellant), the third stage was assembled as three scaled-down Sergeant rocket engines nested in the center of the "tub", and a single modified Sergeant rocket engine and casing comprising the fourth stage was mounted on top of this.[2]

Launch[edit]

Explorer S-46 was launched using a Juno II launch vehicle on 23 March 1960, at 13:35:11 GMT, from LC-26B. Telemetry was lost shortly after the first stage burnout and one second stage motor failed to ignite, resulting in imbalanced thrust and inability to reach orbital velocity. The spacecraft did not achieve orbit.[2]

See also[edit]

References[edit]

  1. ^ "Payload Test Unit of the Satellite S-46". Smithsonian - National Air and Space Museum. March 1993. Retrieved 15 November 2021.
  2. ^ a b c d e "Display:S-46A EXS-46". NASA. 28 October 2021. Retrieved 3 November 2021. Public Domain This article incorporates text from this source, which is in the public domain.