Halley’s Comet

The most famous comet — the first periodic comet recognized; next perihelion 2061.

Also known as: 1P/Halley, Comet Halley

Orbits Sun

Only known short-period comet reliably visible to the naked eye from Earth u2014 a single observer can see it twice in a lifetime.
Last seen in 1986; next perihelion July 2061.
Source of the Eta Aquariid (May) and Orionid (October) meteor showers.
Visited by the Soviet Vega 1 & 2, Japanese Sakigake & Suisei, and ESA's Giotto in 1986.

About Halley’s Comet

1P/Halley is the most famous comet, observed by civilizations since at least 240 BCE and the first object ever recognized as a periodic comet. English astronomer Edmond Halley predicted in 1705 that the comets seen in 1531, 1607 and 1682 were the same object returning every ~76 years, and its recovery in 1758 (16 years after his death) confirmed the prediction. Halley was the first comet to be imaged up close: during its 1986 apparition, the Soviet Vega 1 & 2, Japanese Sakigake & Suisei, and ESA’s Giotto all flew past the nucleus. Giotto passed within 596 km and revealed a dark, 15 × 8 × 8 km potato-shaped nucleus emitting jets of gas and dust on the sunward side.

Physical Properties

Mean radius6 km

Mass2.2e14 kg

Rotation period52.8 h

Bond albedo0.04

Orbit

OrbitsSun

Semi-major axis17.834 AU

Eccentricity0.96714

Inclination162.26°

Perihelion0.586 AU

Aphelion35.082 AU

Orbital period75.32 yr

Gallery

Hand-picked mission imagery of Halley’s Comet sourced from NASA and partner archives. Click any photo for full resolution and source attribution.

The nucleus of Halley's Comet, imaged in 1986 by ESA's Giotto spacecraft. NASA/ESA/Giotto Project · ESA u2014 CC BY-SA 3.0 IGO

Imagery on this page is provided by the original mission teams. Full attribution terms: Image Rights & Credits.

Sources & Further Reading

Numerical values (radius, mass, orbital elements, temperatures) are drawn from NASA NSSDC Planetary Fact Sheets, JPL Horizons, and the JPL Small-Body Database. Last refreshed: 2026-06-08 01:37:02.