This image of the nucleus of Halley's comet comes from the Giotto spacecraft. Click on image for full size version (67K JPG) Image courtesy of JPL

Halley's comet is named after Edmond G. Halley who was the first to suggest that comets were natural phenomena of the solar system, in orbit around the Sun. He suggested that a certain comet was a regular visitor, returning every 76 years, and was, in fact, the same one which had been observed since 240 BC, but in particular in the years 1531, 1607, and 1682, dates which were for him recent history. In 1682 he predicted the comet would return again in 1758, and sure enough, the comet arrived in March 1759. Halley's comet made a particularly bright appearance in 1910. It was also recorded in a famous ancient tapestry after its 1066 appearance.

For hundreds of years humankind has wondered what the nucleus of Halley's comet was really like. This wonderful picture from the Giotto spacecraft gives us the answer. In this picture, the Sun is on the left. Three jets can be seen blowing molecules toward the Sun. A crater can also be seen in the middle right. This image shows that evaporation occurs along specific portions of the comet. Data taken by a suite of spacecraft suggests that the comet is mostly made of ice.

Halley's comet is next scheduled to return in 2062.