Its brightness, longevity, and relative punctuality have made Halley’s Comet a distinctive marker throughout human history. The peanut-shaped Halley’s Comet has trailed its cosmic dust through the solar system every 76 years for at least since 4.5 billion years. In 240 B.C., Chinese astronomers recorded their sightings of Halley’s Comet in the “Records of the Grand Historian.” While the Chinese hold the first known written record of Halley’s Comet, the comet’s name comes from the Englishman Edmond Halley. Edmond Halley proposed that the comet sightings of 1531, 1607, and 1682 were of the same comet and that the comet would return in 1758. His prediction came true when Johann Palizsch, a German farmer and amateur astronomer, sighted Halley’s Comet on Christmas day in 1958.

Statistically, almost everyone living on the earth now, approximately 7 billion people, will not live long enough to see Halley’s Comet slice through the solar system on its next visit in 2061. Halley’s elongated orbit passes well beyond Pluto before it turns to circle back around the sun. During Halley’s last race through the solar system at over 157,000 miles per hour, it had visitors from earth. Five unmanned spacecraft, two from Japan, two from the Soviet Union, and one from the European Space Agency observed Halley’s last visit in 1986. Images revealed that Halley’s Comet is approximately 9 miles long and five miles wide. The comet has several parts. The nucleus is made up of ice, gas, dust, and some other solids. A coma of a diffuse cloud of gas and dust surrounds its nucleus. A highly visible dust tail, an apparitional feature, separates the comet visually from other celestial bodies. The dust tail is over six million miles long. The comet also trails an ion tail that is over 60 million miles long; the ion tail interacts with solar winds. The breathtaking physical presence of Halley’s Comet has stirred some imaginative stories. The most fanciful story repeated is that Pope Calixtus III excommunicated Halley’s Comet because it might be an agent of the devil. History does not support this supposed anecdote.