Comet Halley was visible in 1910 and 1986. The nucleus Comet Halley is 18 times 6 times 6 kilometers. The density of Halley nucleus is very low.

                      Alley is almost unique among comets in that it is both large and active and has a well defined, regular orbit. This made it a relatively easy target for

                     Giotto. But may not be representative of comets in general. its next perihelion passage will be in the early 2062. Comet Halley is probably the most

                      famous comet in history. It is also 4.5 billion years almost same age of the sun! It's orbital period around the sun is about 76 earth days.

                      It's last location was in the Kuiper belt. During the 20th century Comet Halley appeared 1910 and 1986. Using Issac Newton 's law of motion, the

                      astronomer, Edmond Halley made a prediction in 1705. He stated that a comet which had appeared in 1531, 1607, 1682 and 1758. Although   

                      Edmond Halley did not live to see it, but it was named after Edmond Halley.

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