Called 3I/ATLAS, the comet is only the third of its kind known to astronomers, and it’s likely been heading our way for billions of years, carrying pristine material from another star system ...

Harvard astrophysicist Avi Loeb has cowritten a research paper speculating whether the comet 3I/ATLAS is in fact "hostile" ...

The outer solar system is a vast and mysterious place that could be harboring hidden objects we know almost nothing about — from the elusive Planet Nine and baby black holes to interstellar ...

And one day, the solar system will cease to exist. But when will the solar system end? And how will it die out? The answers to those questions depend on how we define the death of the solar system.

Astronomers have revealed new research showing that millions of new solar system objects are likely to be detected by a brand-new facility, which is expected to come online later this year.

Astronomers have discovered that Saturn has thrown a newly found comet on its way out of the solar system. Comet A117uUD is expected to go interstellar at 6,700 mph.

After a decade-long search, some scientists say a growing number of clues point to the existence of a hidden planet in the Kuiper Belt beyond Neptune — and they may soon have the opportunity to ...

This artist’s concept depicts one of the solar system’s inner planets slamming into Earth after being nudged on a collision course by a passing star. Such a world-shattering cataclysm is ...