NASA’s Mariner 9 became the first spacecraft to orbit another planet when it entered Mars’ orbit.
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NASA launched the Mars Observer, a space probe designed to study Mars' geology and climate.
Water-bearing minerals were discovered on Mars by NASA's Curiosity Rover.
A conjunction of Sun, Mercury, Venus, Mars, Jupiter, Saturn, and the Moon occurred.
The US Mariner 9 was launched – it went on to become the first satellite to orbit Mars.
NASA declared the conclusion of the Phoenix mission after contact was lost with the Phoenix lander.
