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- Halley's Comet is certainly the most famous of all comets. It has been observed at every
- return by people all over the world since 164 B.C..
- Halley's comet was first sighted by ancient
- Chinese astronomers in 1059 B.C..
- However, it was not until centuries later that astronomers
- realized that comet Halley was in a circular orbit, and returned at regular intervals.
-
- Edmond Halley, the English astronomer, observed the comet in 1682. He calculated the orbit,
- and realized that it was very similar to the orbits of comets previously observed in 1607 and 1531.
- Based on this information, Halley felt fairly secure in predicting that the comet would return once
- again in 1758.
-
- On Christmas eve of 1758 long after the death of Edmond Halley, a German amateur astronomer
- spotted the comet. Halley's Comet, as it came to be known, reached its closest approach to the
- Sun in March 1759, well within the limits of error given by Halley. This was the first time that the
- return of a comet had been predicted. Before this, it was generally believed that comets traveled
- in straight lines.
-
- Halley's Comet was photographed for the first time in 1910, and was not observed again until
- October, 1982. As Halley made its closest approach to the Sun in 1986, an armada of
- international spacecraft intercepted the famous comet in space.
-
- Two Russian spacecraft called VeGa 1 and VeGa 2, two Japanese spacecraft called Sagikake and
- Suisei, and a European spacecraft called Giotto formed the fleet of space probes that investigated
- Halley's Comet. The most daring of these probes was Giotto, which thrust straight through the
- coma of the comet and survived with only a little damage to some instruments.
-
- Unfortunately for viewers on Earth, Halley's visit in 1986 was not a spectacular sight, as the
- comet approached the Sun opposite from the Earth's orbital position. Halley's Comet will return
- again in the year 2062, and will no doubt be examined even more closely than before.
-
- In the year 2138, Halley's Comet will pass close to the Earth, providing a dazzling show with a
- bright tail millions of miles long. Particles from the comet's tail may even fall on the Earth,
- creating luminous meteor showers in the night sky. However, as with all comets and asteroids
- that cross the orbit of the Earth, it will also serve as a reminder of the dangers posed by these
- wandering bodies.