What was launched first, The Wide Field Infrared Explorer or The Orbiting Astronomical Observatory 2?
Wide Field Infrared Explorer: The Wide Field Infrared Explorer (WIRE) was a satellite launched on March 5, 1999, on the Pegasus XL rocket into polar orbit between 409 and above the Earth's surface. Orbiting Astronomical Observatory 2: The Orbiting Astronomical Observatory 2 (OAO-2, nicknamed Stargazer) was a space observatory launched on December 7, 1968.
The Orbiting Astronomical Observatory 2