interstellar object
ʻOumuamua
The first known visitor from another star system, a strangely elongated or flattened object that sped through in 2017.
- Distance from Earth today
- 8.14 billion km54.40 AU · light: 7 h 32 min
- Distance from the Sun today
- 8.25 billion km55.18 AU
- As of
- 3 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
- Rotation period
- 7.9 h
- Perihelion
- 0.267 AU
- Orbital period
- none – open (hyperbolic) orbit
- Orbital eccentricity
- 1.209
- Orbital inclination
- 123.1°
- Perihelion passage
- 7 September 2017
- Minimum orbit distance from Earth’s orbit (MOID)
- 0.096 AU (14.33 million km)
Source of the figures: JPL Small-Body Database (public domain).
Discovery: 2017 – Pan-STARRS1 survey (Robert Weryk)
Description
ʻOumuamua was the first object confirmed to have come from outside the Solar System. It was spotted in October 2017 by the Pan-STARRS1 telescope in Hawaii, already on its way out after passing the Sun, moving too fast to be bound to our star. Its brightness varied dramatically as it tumbled, suggesting an unusually elongated or flattened shape. It showed no visible coma, yet its motion revealed a slight extra push away from the Sun, which has been explained by escaping gases that were too faint to see. The Hawaiian name roughly means a scout or messenger from afar arriving first.