3I/ATLAS
From the UAP Encyclopedia, the open encyclopedia of UFO and UAP history · 🗓️ Event
Contents 4
| Type | Event |
|---|---|
| Also known as | C/2025 N1 (ATLAS), 3I |
| Discovered | 1 July 2025 |
| By | ATLAS survey telescope, Río Hurtado, Chile |
| Closest to the Sun | About 29–30 October 2025, about 1.4 AU |
| Closest to Earth | About 1.8 AU, 19 December 2025 |
3I/ATLAS is a comet from interstellar space and the third interstellar object ever found, after ʻOumuamua (2017) and 2I/Borisov (2019). It was reported on 1 July 2025 by the NASA-funded ATLAS survey telescope in Río Hurtado, Chile. Astronomer Avi Loeb's suggestions that it could be alien technology made it one of the most searched space topics of 2025. Observations show it behaves like a comet, and NASA says it posed no threat to Earth.[1][2][3]
Discovery and path
Its very high speed — about 58 km/s relative to the Sun before the Sun's pull sped it up — and its open, hyperbolic path showed it came from outside the Solar System and will not return. Earlier images from June 2025 were found in survey archives after the discovery.[1][2]
It passed closest to the Sun around 29–30 October 2025, a little inside the orbit of Mars, at about 1.4 times Earth's distance from the Sun. Its closest approach to Earth, on 19 December 2025, was about 1.8 AU — some 270 million km.[1]
What it is made of
Telescopes including Hubble and the James Webb Space Telescope saw a cloud of gas and dust (a coma) and a tail, with a lot of carbon dioxide. NASA's estimate of the solid core's size ranged from about 440 metres to 5.6 kilometres across. Some researchers have suggested it could be older than the Solar System, having formed around another star billions of years earlier.[1][3]
The alien-technology debate
Loeb wrote a series of articles listing features he considered anomalous, and argued that the possibility of an artificial object should be taken seriously. Other astronomers responded that its behaviour matches a natural comet. Interest peaked in late 2025 and has since faded, while scientists continue to study the data.[3]
References
- Quick facts about 3I/ATLAS — NASA Science · science.nasa.gov
- What is comet 3I/ATLAS? — The Planetary Society · planetary.org
- How did interstellar comet 3I/ATLAS capture our imagination in 2025? — Space.com · space.com
This page was last edited on 14 November 2026. Articles are written in our own words from the sources listed under References; disputed claims are attributed to the people who made them.
No discussion yet.