NASA launched the last space probe in the Mariner Program, Mariner 10.
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Japan launched its first lunar probe, Hiten, from the Uchinoura Space Center.
The USSR launched the Sputnik III.
The world's first satellite navigation system, Transit 1-B, was successfully launched from the US.
STS 77 (Endeavour 11) was launched into orbit.
The unmanned space mission Luna 21 was launched.