Astronomers have confirmed that 3I/ATLAS is a new interstellar object that is currently passing through our solar system. This makes it the third object of its kind ever found, following ʻOumuamua in 2017 and 2I/Borisov in 2019.
It was first spotted on July 1, 2025, by the ATLAS telescope in Chile and was confirmed by the Minor Planet Center the following day. 3I/ATLAS is traveling very quickly, on a hyperbolic trajectory, which means that it is not bound to the Sun and will pass through the solar system.
3I/ATLAS is displaying properties of a comet, including faint tail and the presence of gas and dust surrounding its nucleus. Initial analyses suggest an estimate of between 10 and 20 kilometers in size, possibly making it the largest ever interstellar object detected.
It will reach its closest distance to the Sun, estimated to be just inside the orbit of Mars, in late October 2025. There should be no threat to Earth from the passage of 3I/ATLAS, as its current hyperbolic trajectory keeps it at a confident distance.
Telescopes around the world are now keeping an eye on the object as it moves through the inner solar system.
🚨BREAKING: Interstellar object passing through the solar system
— Hardwire Media (@HardwireMedia) July 3, 2025
3I/ATLAS, confirmed as the third interstellar object, follows a hyperbolic orbit (eccentricity ~6) through our solar system. First spotted by ATLAS on July 1, 2025, it will pass closest to the Sun on October 30 at… pic.twitter.com/SmV2C2ORl3
What Scientists Hope to Learn from 3I/ATLAS
This observation provides a rare opportunity for scientists to study material from outside of our solar system. Since interstellar objects are really rare, every single object that is spotted helps scientists understand how other star systems form and evolve.
Unlike most comets or asteroids that orbit the Sun, interstellar objects such as 3I/ATLAS were formed around a different star and expelled into space.
Both the size of 3I/ATLAS and its visible comet-like activity have made it particularly interesting. Scientists are optimistic that by looking at the object's structure and composition, it will reveal some insight into dust, ice, and gases that exist outside of our solar system.
If conditions allow, astronomers will also try to measure the object's light spectrum to find out what chemicals it contains.
Over the next couple of months, the researchers will keep following the object to observe it as it makes its way out of the solar system. Machines like the soon-to-be-constructed Vera C.
Rubin Observatory are expected to reveal many more like this in the future. So, while 3I/ATLAS seems fairly unique, it allows researchers to learn more about the universe outside of our planetary system.
