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.

A renowned physicist believes he's cracked the mystery of where a giant unidentified object hurtling through our solar system ...

When white dwarfs—the hot remnants of stars like our sun—are orbited closely by another star, they sometimes steal mass away ...

An attosecond—or 0.000000000000000001 second—is no time at all for a person. That is not so for electrons, atoms and ...

Dennis Mammana Stargazers We live in a world defined by inches, feet and miles (or centimeters, meters and kilometers, if you prefer), and it’s not difficult for most of us to comprehend sizes and ...

An object dubbed 3I/ATLAS is only the third interloper from outside the Solar System seen in all of human history.

We have discovered two interstellar objects so far, ’Oumuamua and Comet 2I/Borisov. ’Oumuamua had no dust tail and a ...

Harvard physicist Avi Loeb revealed that the object is expected to approach Earth on December 17, speeding through the solar ...

For only the third time in history, astronomers have detected a new interstellar visitor — an object from another star — blitzing into our solar system.

Astronomers are scrambling to gather data on a mysterious object that’s currently hurtling through the solar system.

An object from another star has been seen entering the solar system at high speed, and is expected to whip around the sun in ...