Halley's Comet

space · comets · astronomy · visitors from afar

A regular visitor. Halley's Comet returns to the inner Solar System about every 75 to 76 years, making it the most predictable comet we know of. That's why people can plan to see it, unlike most comets that surprise us!

Naked eye wonder. This comet is special because you can actually see it without a telescope or binoculars if you know where to look and the sky is dark enough. Most comets are too faint or far away for that.

Official number name. Scientists call it 1P/Halley, where the 1P means it was the first periodic comet ever discovered and numbered. The P stands for periodic, since it returns on a regular schedule.

Last visit in 1986. The most recent time Halley's Comet came close to Earth was 1986, and astronomers got a fantastic view of it from spacecraft that flew right past it. The next time it will visit is around 2061.

Icy dirty snowball. Like all comets, Halley is mostly frozen water, rock, and dust held together by gravity. As it gets closer to the Sun, the heat makes it glow and stream a glowing tail millions of miles long.