A mysterious, ice-rich comet named 3I/ATLAS has entered our solar system — and it may be the oldest comet ever observed.
Estimated to be over 7 billion years old, this interstellar visitor likely originated from the Milky Way’s thick disk, far beyond the familiar realm of our Sun and planets.
Discovery of a Possible Ancient Comet
A newly identified interstellar object could be the oldest comet ever detected, with scientists suggesting it might have formed more than three billion years before our solar system.
Named 3I/ATLAS, this icy traveler is rich in water and is only the third known object to visit us from outside the solar system.
What makes it even more unusual is that it appears to have arrived from an entirely different part of the Milky Way than any of its predecessors.
This mysterious object could be more than seven billion years old, according to University of Oxford astronomer Matthew Hopkins.
He believes 3I/ATLAS might be the most extraordinary interstellar object scientists have studied so far.
An Origin in the Milky Way’s Thick Disk
Unlike the previous two objects to enter our solar system from elsewhere in the cosmos, 3I/ATLAS appears to be traveling on a steep path through the galaxy, with a trajectory that suggests it originated from the Milky Way’s ‘thick disk’ – a population of ancient stars orbiting above and below the thin plane where the Sun and most stars reside.
“All non-interstellar comets, such as Halley’s comet, formed within our solar system, so they are up to 4.5 billion years old.”
“But interstellar visitors have the potential to be far older, and of those known about so far, our statistical method suggests that 3I/ATLAS is very likely to be the oldest comet we have ever seen.”
