Salyut 2
Salyut 2 was launched
April 3,
1973. It was not really a part of the same program as the other
Salyut space stations, instead being the highly classified prototype military space station
Almaz. It was given the designation Salyut 2 to conceal its true nature. Despite its successful launch, within two days the as-yet-unmanned Salyut 2 began losing pressure and its flight control failed; the cause of the failure was likely due to shrapnel piercing the station when the discarded
Proton rocket upper stage that had placed it in orbit later exploded nearby.
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