Vanguard SLV-6

Vanguard SLV-6
Vanguard rocket on LC-18A prior to its launch
NamesVanguard Space Launch Vehicle-Six
Mission typeSolar heating of Earth
OperatorNaval Research Laboratory
Mission durationFailed to orbit
Spacecraft properties
SpacecraftVanguard 3B
Spacecraft typeVanguard
ManufacturerNaval Research Laboratory
Launch mass10.8 kg (24 lb)
Dimensions50.8 cm (20.0 in) of diameter
Start of mission
Launch date22 June 1959, 20:16:09 GMT
RocketVanguard SLV-6
Launch siteCape Canaveral, LC-18A
ContractorGlenn L. Martin Company
End of mission
Decay dateFailed to orbit
Orbital parameters
Reference systemGeocentric orbit (planned)
RegimeMedium Earth orbit
Perigee altitude655 km
Apogee altitude3840 km
Inclination34.20°
Period134.0 minutes

Vanguard SLV-6, also called Vanguard Satellite Launch Vehicle-Six, hoped to be the third successful flight of the American Vanguard rocket following the successful Vanguard 2 satellite on rocket Vanguard SLV-4. Vanguard Satellite Launch Vehicle-6 (SLV-6) was designed to carry a small spherical satellite into Earth orbit to study solar heating of Earth and the heat balance. A faulty second stage pressure valve caused a mission failure.