Flights to Saturn
In 1973, the United States launched a space probe to study both Saturn and Jupiter. This craft, called Pioneer-Saturn, sped by Jupiter in 1974 and flew within 13,000 miles of Saturn on Sept. 1, 1979. The probe sent back scientific data and close-up photographs of Saturn. The data and photographs led to the discovery of two of the planets outer rings.
Pioneer-Saturn also found that the planet has a magnetic field, which is 1,000 times as strong as that of Earth. This field produces a large magnetosphere around Saturn. In addition, data from the probe indicated the presence of radiation belts inside the planets magnetosphere. The belts consist of high-energy electrons and protons, and are comparable to Earths Van Allen belts.
In 1977, the United States launched two space probes -- Voyager 1 and Voyager 2 -- to study Saturn and other planets. Voyager 1 flew within 78,000 miles of Saturn on Nov. 12, 1980. On Aug. 25, 1981, Voyager 2 flew within 63,000 miles of the planet.
The Voyager probes confirmed the existence of Saturns seventh ring. They also found that the planets rings are made up of ringlets. In addition, the probes sent back data and photographs that led to the discovery or confirmation of the existence of nine satellites. The Voyager probes also determined that the atmosphere of Titan consists chiefly of nitrogen. In 1997, the United States launched the Cassini probe to study Saturn, its rings, and its satellites. The probe began orbiting Saturn in 2004. Cassini also carried a probe called Huygens, which was to separate from Cassini and land on Titan. Huygens was built by the European Space Agency, an organization of European nations.
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