Science

Unlocking the Secrets of 3I/Atlas: The Oldest Comet Ever Discovered?

2025-07-11

Author: Ming

A Cosmic Wonder from Beyond

Astronomers have made an astonishing discovery: a mysterious interstellar object dubbed 3I/Atlas could potentially be the oldest comet ever observed, predating our own solar system by a staggering three billion years! This revelation comes from a dedicated team at the University of Oxford.

A Historic Find in the Night Sky

3I/Atlas marks a significant milestone in astronomy—only the third known object to be spotted originating from outside our solar system. Details of this monumental finding were shared at the UK’s Royal Astronomical Society meeting held in Durham last Friday.

"The excitement surrounding 3I/Atlas is palpable," stated Matthew Hopkins, an Oxford astronomer who recently completed his PhD focused on interstellar discoveries. "For the first time in my studies, we actually found one!"

A Glimpse into Ancient Space

First detected on July 1, 2025, by the Atlas survey telescope in Chile, 3I/Atlas was initially 670 million kilometers away from the Sun. Currently, it is nestled about the same distance from Earth as Jupiter, requiring large telescopes for visibility.

A Journey Through the Milky Way

Hopkins suggests that the comet likely originates from the Milky Way's "thick disk," a cluster of ancient stars situated above and below where most stars—including our Sun—commonly reside. Stunningly, initial data indicates that 3I/Atlas could be up to seven billion years old, making it a remarkable visitor from the depths of space.

Water Ice and a Glowing Tail

What makes this discovery even more fascinating is the belief that 3I/Atlas is composed largely of water ice, given its probable formation around an ancient star. As it approaches the Sun later this year, the intense solar energy could heat its surface, sending plumes of vapor and dust flying—potentially creating a dazzling tail visible from Earth!

A Galaxy Full of History Awaiting Discovery

As Prof. Chris Lintott, a study co-author, notes, "This object offers a glimpse into a part of the galaxy we've never observed up close before." The team estimates a two-thirds chance that this comet is older than our solar system and has been traveling through interstellar space for eons.

What Lies Ahead for 3I/Atlas?

In the months to come, 3I/Atlas is expected to become visible to amateur astronomers. Before its appearance, only two other interstellar visitors—1I/'Oumuamua in 2017 and 2I/Borisov in 2019—had been identified. With the upcoming launch of the powerful Vera C Rubin telescope in Chile, scientists anticipate discovering between five and fifty new interstellar objects, revolutionizing our understanding of cosmic history.

Stay tuned as we watch this cosmic wanderer grace our skies!