A mystery interstellar object discovered last week is likely to be the oldest comet ever seen – possibly predating our solar system by more than three billion years, researchers say. The "water ...

I/ATLAS might be over 7 billion years old, a new study reports, which would make it the oldest comet known. But experts caution we need more data.

Scientists now say an interstellar comet discovered earlier this month could be one of the oldest that astronomers have ever encountered.

However, new research has shown this potentially "water ice-rich" visitor could be even more extraordinary than initially ...

The icy traveler, called 3I/ATLAS or Comet ATLAS, was discovered on July 1 by the NASA -funded ATLAS survey telescope in Río Hurtado, Chile. This enormous space snowball came from the direction of the ...

A mystery interstellar object discovered last week is likely to be the oldest comet ever seen—possibly predating our solar ...

On June 14 and 16, technicians installed solar panels onto NASA's Nancy Grace Roman Space Telescope, one of the final steps ...

Key PointsComet 3I/ATLAS, discovered on July 1, 2025, by the ATLAS telescope in Chile, is only the third confirmed interstellar object observed in our solar system. The comet is traveling at an ...

Just the third-ever confirmed interstellar object has been detected in our solar system. Here's what we know. (Spoiler: It's ...

A Gigantic Megacomet Is Erupting as It Zooms through the Solar System Recent observations have revealed carbon monoxide venting from the largest comet ever seen, providing clues about its origins ...

A nearby star drifts into the outskirts of our solar system. Its gravity disturbs the Oort Cloud and alters the orbits of far-out objects.

Learn how a possible ninth planet, the theoretical Planet X, could have acquired its wide orbit in the outer Solar System — a process that’s also applicable for other planets.