A periodic
comet named for
Edmond Halley, who observed it in 1682 and identified it as the one observed in 1531 and 1607.
Halley did not live to see its return in 1758, close to the time he predicted.
It reappeared in 1835 when it was carefully recorded by visual observers, and in 1910, when its long tail and outbursts of dust jets were observed photographically.
For its most recent return in 1985 and 1986, astronomers observed it from the ground and from space. A massive observing effort (1982–89) including visual observations, photography, and studies of the area around the nucleus, was coordinated by the International Halley Watch.
Japan, the European Space Agency, and the USSR sent spacecraft to study the comet; the Vega and Giotto probes revealed a darker-than-expected nucleus 8 km (5 mi) wide and 15 km (9 mi) long, and shaped like a potato.
Incidentally, Samuel Clemens (better known by his pen name Mark Twain) was born in 1835, and often claimed he was born in the year of the Comet, and would also die in the year of the Comet. He was proved right, dying in 1910.