Question

Motion of halley's comet (period time? )

Answer 1

Halley's Comet or Comet Halley, officially designated 1P/Halley, is a short-period comet visible from Earth every 74–79 years. Halley is the only known short-period comet that is regularly visible to the naked eye from Earth, and the only naked-eye comet that might appear twice in a human lifetime. 

Answer 2

2061. The next predicted perihelion of Halley's Comet is 28 July 2061, when it is expected to be better positioned for observation than during the 1985–1986 apparition, as it will be on the same side of the Sun as Earth.

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