Marshall Space Flight Center of the launch vehicle. Finally, on April 24, 1990, on Mission STS-31, Shuttle "Discovery" launched the Hubble telescope successfully into its planned orbit. Almost immediately it was realized that the optical performance was not as expected; analysis of the flawed images showed that the primary mirror had been ground to the wrong shape, resulting in spherical aberration. Fortunately, the Hubble telescope had been designed to allow in-space maintenance, and in December 1993, mission STS-61 carried astronauts to the Hubble to make corrections and change some components. A second repair mission, STS-82, was made in February 1997, and a third, STS-103,
Space Shuttle machine "Space Shuttle" was produced by Zaccaria and a 1984 pinball machine "Space Shuttle: Pinball Adventure" was produced by Williams and features a plastic Space Shuttle model among other artwork of astronauts on the play field. The Space Shuttle also appears in a number of flight simulator and space flight simulator games such as "Microsoft Space Simulator", "Orbiter", "FlightGear", "X-Plane" and Space Shuttle Mission 2007. Several Transformers toys were modeled after the Space Shuttle. The U.S. Postal Service has released several postage issues that depict the Space Shuttle. The first such stamps were issued in 1981, and are on display