Names | Vanguard Space Launch Vehicle-4 |
---|---|
Mission type | Weather satellite Air Density Experiment |
Operator | Naval Research Laboratory |
Harvard designation | 1959 Alpha 1 |
COSPAR ID | 1959-001A |
SATCAT no. | 00011 |
Mission duration | Weather observation: 19 days (achieved) 65 years, 7 months and 28 days (in orbit) |
Spacecraft properties | |
Spacecraft type | Vanguard 2E |
Bus | Vanguard |
Manufacturer | Naval Research Laboratory |
Launch mass | 10.75 kg (23.7 lb) |
Dimensions | 50.8 cm (20.0 in) of diameter |
Start of mission | |
Launch date | 17 February 1959, 15:55:02 GMT[1] |
Rocket | Vanguard SLV-4 |
Launch site | Cape Canaveral, LC-18A |
Contractor | Glenn L. Martin Company |
End of mission | |
Last contact | 15 March 1959 |
Decay date | 2259 (estimated) ~ 300 years orbital lifetime [2] |
Orbital parameters | |
Reference system | Geocentric orbit[3] |
Regime | Medium Earth orbit |
Perigee altitude | 559 km (347 mi) |
Apogee altitude | 3,320 km (2,060 mi) |
Inclination | 32.88° |
Period | 125.80 minutes |
Instruments | |
Optical scanner Radio beacon | |
Vanguard 2 (or Vanguard 2E before launch) is an Earth-orbiting satellite launched 17 February 1959 at 15:55:02 GMT, aboard a Vanguard SLV-4 rocket as part of the United States Navy's Project Vanguard.[4] The satellite was designed to measure cloud cover distribution over the daylight portion of its orbit, for a period of 19 days, and to provide information on the density of the atmosphere for the lifetime of its orbit (about 300 years).[5][6] As the first weather satellite and one of the first orbital space missions, the launch of Vanguard 2 was an important milestone in the Space Race between the United States and the Soviet Union.[7][8][5] Vanguard 2 remains in orbit.
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