Comet Halley

Definition

Comet Halley, also known as Halley's Comet, is a periodic comet visible from Earth every 75–76 years. It is one of the most well-known and bright comets, with its last appearance in 1986 and next expected in 2061.

5 Must Know Facts For Your Next Test

1. Halley's Comet is named after Edmond Halley, who accurately predicted its return in 1758.
2. It has an orbital period of approximately 75-76 years, making it a short-period comet.
3. The comet's nucleus is about 15 kilometers long and composed of ice, dust, and organic compounds.
4. Halley's Comet was the first comet to be observed in detail by spacecraft during its 1986 visit.
5. Its appearances have been recorded since at least 240 BC, influencing various cultures and historical events.

Review Questions

• Who predicted the return of Comet Halley?
• What is the approximate orbital period of Halley's Comet?
• During which year did spacecraft observe Halley's Comet in detail?

Related terms

Oort Cloud: A spherical shell of icy objects surrounding the solar system that are believed to be the source of long-period comets.

Kuiper Belt: A region beyond Neptune filled with small icy bodies and dwarf planets, thought to be the origin of short-period comets like Halley's.

Meteor Shower: An event where numerous meteors are observed radiating from a specific point in the night sky, often caused by Earth passing through debris left by comets.