Aster › Space program › 3I/ATLAS
3I/ATLAS
Position on the route: 71/181 · level needed 500 · journey (Mk0 engine) 25.3 h
By the numbers
| Speed | ≈ 58 km/s |
|---|---|
| Found | 1 July 2025 |
| Perihelion | 29 October 2025, 1.36 AU |
| Age | billions of years (estimate) |
The story
3I/ATLAS is the third interstellar object to pass through the Solar System, found on 1 July 2025 by the ATLAS survey telescope (Río Hurtado, Chile). Its speed of about 58 km/s is far above the first two.
It came within 1.36 AU of the Sun on 29 October 2025 and passed close to Mars, and by Jupiter in March 2026. It is thought to come from the Galaxy’s thick disc and to be billions of years old; it showed a coma rich in carbon dioxide. The position here is approximate.
Missions
- Hubble, JWST, Mars and Jupiter craft: observations (no mission)
Colony note
A passing visitor; an observation outpost only.
What probes bring back
- The ATLAS survey telescope in Chile found it on 1 July 2025: the third interstellar object to pass through the Solar System (3I). Its speed is about 58 km/s, the fastest of the three.
- It came within 1.36 AU of the Sun on 29 October 2025 and passed close to Mars. It may come from the Galaxy’s thick disc and be billions of years old; it went by Jupiter in March 2026.