7 billion years of solitude: Interstellar visitor to be visible from Earth

A mysterious interstellar object spotted by astronomers last week may be the oldest comet ever seen, according to scientists .

The team from Oxford University suggests that this object, called 3I/Atlas, could be 3 billion years older than our own solar system.

The preliminary findings were presented today at the Royal Astronomical Society's national meeting in Durham, England. "3I/Atlas has us all very excited," astronomer Matthew Hopkins of the University of Oxford told BBC News. Based on the object's speed, Hopkins said it could be over 7 billion years old and could be the most remarkable interstellar visitor yet.

AS FAR AS JUPITER 3I/Atlas was first spotted on July 1, 2025, by the Atlas survey telescope in Chile, when it was about 420 million miles (670 million km) from the Sun. Currently visible only with very large telescopes, it is about as far from Earth as Jupiter. Since then, astronomers around the world have been racing to pinpoint its path and discover more about it.

Hopkins believes this is due to the Milky Way's "thick disk," a group of old stars orbiting above and below the Sun and most other stars. The team believes 3I/Atlas is likely composed of a large amount of water ice because it formed around an old star. This means that when it approaches the Sun later this year, solar energy will heat the object's surface, causing flares of vapor and dust. This could create a glowing tail.

"NEVER SEEN CLOSE UP"

"This is an object from a part of the galaxy we've never seen up close before," said co-author Prof. Chris Lintott. "We think there's a two-in-three chance this comet is older than our solar system and has been drifting through interstellar space ever since." Hopkins noted that interstellar objects form around other stars at the beginning of their lives, adding, "This connection with their parent star means we can look at the stellar population of the Milky Way." Later this year, 3I/Atlas will be visible from Earth with amateur telescopes. Only two other comets had been seen before 3I/Atlas became visible: 1I/'Oumuamua, discovered in 2017, and 2I/Borisov, discovered in 2019.