Forty-five years ago today — April 8, 1966 — an Atlas Agena rocket launched from Cape Canaveral and placed the OAO-1 space telescope in a “nearly perfect circular orbit.”
(Artist’s conception of OAO-1. NASA image.)
The first of the orbiting observatories that would be precursors to the Hubble Space Telescope, OAO-1 did not live up to expectations. Only 7 minutes after separation, the power system failed due to high voltage arcing in the star trackers and resultant battery depletion. Ground controllers ended the mission after 20 orbits, and the first of the OAO series made no celestial observations.
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