Vanguard 1 is a US satellite, the fourth artificial Earth-orbiting satellite launched on March 17, 1958, following Sputnik 1, Sputnik 2, and Explorer 1. Vanguard 1 was the first solar-powered satellite. It was designed to test the launch capabilities of a three-stage launch vehicle as a part of Project Vanguard, and the effects of the space environment on a satellite and its systems in Earth orbit.
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| Vanguard 1 launch cover with Goldcraft cachet. |
Although communications with the satellite were lost in 1964, it remains the oldest human-made object still in orbit, together with the upper stage of its launch vehicle.
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| Vanguard 1 launch cover with H.Flick cachet. |
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| Vanguard 1 launch cover with Sarzin cachet. |
(Reference from
Vanguard 1)
