Thirty-five years ago today — June 19, 1976 — Viking-1 arrived at Mars.
(Viking-1 orbiter. NASA image.)
The Viking-1 orbiter spent a month imaging the red planet while mission controllers picked the best spot for its lander. The orbiter released the lander on July 20th.
The orbiter shut down its mission operations during the solar conjunction (when the Earth was on the opposite side of the Sun from Mars) from November 5 until December 14, 1976. The orbiter continued to function until August 17, 1980.
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