Space Telescope orbit the earth hundreds of kilometers above the ground, their instruments collecting light from stars and galaxies. Telescopes in space have a clearer view than those on earth, because they are unaffected by the earth's atmosphere, which absorbs or d distort m much of this radiation. There are a variety types of space telescopes designed to observe different types of light. The Hubble Space Telescope observes infra-red, ultraviolet, and visible light. It can detect objects that are 100times fainter than those any telescopes on earth can see. When this 11,000 kilograms, 13metre long telescope was launched by the Space shuttle in 1990, it was found that it's primary mirror was faulty and it's images were blurred. Astronauts fitted extra optics to correct the problem in 1993.
Space probes have visited every planet in the solar system. They take photographs and gather data that cannot be collected using Earth-based equipment. Some probes fly past or orbit around planets or moons, while others land. Two Voyager space probes flew past outer planets in the 1970s and 1980s. Two Viking spacecraft landed on Mars in 1976. The Magellan spacecraft orbited Venus from 1989 and mapped it's surface. The Pathfinder spacecraft landed on Mars in 1997 and released a rover vehicle to explore the surface.
