Cosmonaut Alexey Leonov made the first spacewalk when he left his Voskhod 2 spacecraft.
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NASA's New Horizons space probe completed the first flyby of Pluto in the history of human spaceflight.
The Mariner 1 Space Probe was forced to self-destruct minutes after launching.
The New York Times published Edwin Hubble's discovery that the Andromeda 'nebula' is actually a galaxy.
The first pizza party was held in space.
The world's first person visited space.
