Halley's Comet Returns Soon
Halley's Comet is a short-period comet visible from Earth roughly every 76 years. It last visited in 1986. Astronomers recorded its return in 240 BC.
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Halley's Comet is a short-period comet visible from Earth roughly every 76 years. It last visited in 1986.
Astronomers recorded its return in 240 BC. Ancient Chinese observations helped constrain later orbit calculations.
A passage in the Babylonian Talmud mentions a star appearing once in seventy years. First-century Mesopotamian astronomers might have known.
Jamaican astronomer Francis Williams independently observed the 1759 return.
In March 1986, the Giotto spacecraft visited. It observed Halley's nucleus in detail for the first time.
Halley's Comet will remain active for a long time.
Fred Whipple called comets dirty snowballs. Halley is a mixture of volatile ices and dust.
Halley will next appear in mid-2061. After another 2,300 perihelion passages, it will likely disappear completely.