Vanguard 2 is a U.S. Earth-orbiting satellite that was launched on February 17, 1959, at 15:55:02 GMT, aboard a Vanguard SLV-4 rocket as part of the United States Navy's Project Vanguard. Its primary purpose was to measure cloud cover distribution during the daylight portion of its orbit for a duration of 19 days and to provide data on atmospheric density for the expected lifespan of its orbit, which is approximately 300 years. As the first weather satellite and one of the earliest orbital space missions, the launch of Vanguard 2 marked a significant milestone in the Space Race between the United States and the Soviet Union.
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| Vanguard 2 "Goldcraft" launch cover postmarked at Port Canaveral on February 17, 1959. |
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| Vanguard 2 "Sarzin" launch cover postmarked at Port Canaveral on February 17, 1959. |
(Reference from
Vanguard 2)
