The Gemini V spacecraft returned to Earth, landing in the Atlantic Ocean.
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NASA launched the Mariner 4 space probe on a mission to Mars.
Viking I lands on Mars.
NASA launched the Pioneer 11 space probe to study the asteroid belt & the environment around Jupiter and Saturn.
Sputnik 2 soviet spacecraft burned up, returning through Earth's atmosphere.
The Soviet spacecraft Venera 9 went into Venus' orbit – making it the first to do so.