Halley-type comet
Comet Swift–Tuttle
The large periodic comet behind the Perseids, the bright meteor shower that peaks every August.
- Distance from Earth today
- 6.50 billion km43.44 AU · light: 6 h 1 min
- Distance from the Sun today
- 6.44 billion km43.06 AU
- As of
- 2 November 2026position from NASA/JPL orbital elements
Where it is today
Top view of the plane of Earth’s orbit, compressed distance scale. Open on the big map with the time slider →
Facts
- Diameter
- 26 km
- Semi-major axis
- 26.17 AU (3.92 billion km)
- Perihelion
- 0.959 AU
- Aphelion
- 51.39 AU
- Orbital period
- 133.9 years
- Orbital eccentricity
- 0.963
- Orbital inclination
- 112.8°
- Last perihelion
- 17 December 1992
- Next perihelion
- 14 November 2126 (approximate)
- Minimum orbit distance from Earth’s orbit (MOID)
- 0.001 AU (133,500 km)
Source of the figures: JPL Small-Body Database (public domain).
Discovery: 1862 – Lewis Swift and Horace Tuttle
Description
Swift–Tuttle was discovered independently by Lewis Swift and Horace Tuttle in 1862. It travels on a long, steeply inclined orbit that brings it back roughly every 133 years; its most recent passage was in 1992, and it is next expected in 2126. It is notable for having a large nucleus for a periodic comet. Every August, Earth passes through the trail of dust it has left behind, producing the Perseid meteor shower, one of the most popular sky events of the year.