Viking 1 Lands on Mars
NASA's Viking 1 became the first spacecraft to successfully land on Mars and transmit photographs from the surface, while conducting experiments to search for life.
On July 20, 1976 — the seventh anniversary of the Apollo 11 Moon landing — NASA's Viking 1 lander touched down on Chryse Planitia on Mars, becoming the first spacecraft to successfully land on the Red Planet and transmit photographs from the surface. The panoramic images revealed a rust-colored, rock-strewn desert under a pink sky. Viking's biology experiments produced ambiguous results: the Labeled Release experiment detected chemical activity that some scientists argued indicated microbial life, while the Gas Chromatograph Mass Spectrometer found no organic molecules. The debate over the Viking biology results continues to this day. Viking 1 operated on the surface for over six years, far exceeding its 90-day design life.
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