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OAO
NASA’s OAO (Orbiting Astronomical Observatory) program was a series of four satellites that launched between 1966 and 1972, two of which were successful. These missions included OAO 2 (Stargazer) and OAO 3 (Copernicus), the direct ancestors of Hubble, Chandra, Swift, and many other astronomy satellites.
Type
Space telescope
First Launch
April 8, 1966
wavelength
Multiwavelength
last launch
Aug. 21, 1972
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An artist's concept of OAO 2, nicknamed Stargazer, in orbit around Earth.
Credit: NASA
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