 However, German scientist Hermann Oberth had first conceived the idea of a space based telescope.Spitzer's proposal called for a large telescope that would not be hindered by Earth's atmosphere.After lobbying in the 1960s and 1970s for such a system to be built, Spitzer's vision ultimately materialized into the world's first space-based optical telescope, Hubble Space Telescope, which was launched on April 20, 1990 by the Space Shuttle "Discovery" (STS-31).