How often is Halley's Comet visible?
Halley's Comet
every 75–76 years
Halley's Comet or Comet Halley, officially designated 1P/Halley,[1] is a short-period comet visible from Earth every 75–76 years.[1][10][11][12] 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.[13] Halley last appeared in the inner parts of the Solar System in 1986 and will next appear in mid-2061.[14]