3I/ATLAS
the third interstellar object · a comet from another star
13 AU from Earth
Found on 1 July 2025 by the ATLAS survey telescope in Chile: only the third object known to come from another star. It swept past the Sun just inside the orbit of Mars and is heading back into interstellar space; its speed hints that it may be older than the Solar System.
- shown as on 29 October 2025, at its closest to the Sun (1.36 AU), moving at 68 km/s
- now 13.2 AU out, leaving at about 58 km/s
- nucleus between 0.44 and 5.6 km across (Hubble)
Numbers that change with time are from 8 November 2026.
open 3I/ATLAS in the atlas ›- kind
- comet or meteor shower
- distance
- 13.2 AU from the Sun
- orbits
- the Sun
More comets & meteors
- Comet NEOWISE the bright comet of July 2020
- Comet Tsuchinshan-ATLAS the bright comet of October 2024
- Comet Shoemaker-Levy 9 the comet that hit Jupiter in July 1994
- Halley's Comet periodic comet
- Comet 67P/Churyumov-Gerasimenko Rosetta's comet
- Comet Hale-Bopp the great comet of 1997
- 'Oumuamua the first interstellar object
- the Perseids meteor shower in August