NASA’s Voyager 1 spacecraft entered interstellar space, becoming the first artificial object to do so.
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The Soviet Union's Luna 17 uncrewed space mission launched.
NASA launched the Columbia Space Shuttle for its final test flight, STS-4.
The unmanned space mission Luna 21 was launched.
A US National Reconnaissance Office mission launched on a reused SpaceX booster for the first time.
The Soviet Union launched the first crewed Soyuz mission, Soyuz 1.
