Named for NASA's second administrator, who led the agency during the development of the Apollo program, the James Webb Space Telescope (JWST) will dwarf its predecessor by most measures. (The project is a collaboration among NASA and the European and Canadian space agencies.) Nearly twice as long as Hubble, and boasting a light-collecting mirror several times larger, JWST will also venture farther afield than its elder counterpart. Whereas Hubble circles Earth at an altitude of less than 600 kilometers, JWST will set up shop 1.5 million kilometers away, well beyond the orbit of the moon.