NASA launched the Viking 1 planetary probe toward Mars.
The Viking 1 was the first successful Mars lander in history.
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NASA launched the Mars Science Laboratory probe, which carried the Curiosity Rover to Mars.
A conjunction of Sun, Mercury, Venus, Mars, Jupiter, Saturn, and the Moon occurred.
NASA declared the conclusion of the Phoenix mission after contact was lost with the Phoenix lander.
NASA launched the Mars Observer, a space probe designed to study Mars' geology and climate.
NASA launched its Mariner 7 space probe from Cape Canaveral atop an Atlas-Centaur rocket.
