Across July 14-15, 1965 (depending on your time zone), the Mariner 4 mission was doing something incredible. This early NASA mission performed the first flyby of Mars and took the first close-up ...

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"That Mars is habitable by beings of some sort or other is as certain as it is uncertain what these beings may be," wrote Percival Lowell in the early 20th century. While the theories of this ...