Interstellar comet 3I/ATLAS makes closest approach to Sun

Technology Oct 30, 2025

On October 29, interstellar comet 3I/ATLAS made its closest swing by the Sun—just inside Mars's orbit—before heading out of our solar system for good.
Spotted by astronomers in Chile this July, it's only the third known visitor from beyond our solar neighborhood.

Comet won't return for another million years

3I/ATLAS is on a one-way trip through our skies and won't be back.
It'll show up again in late November after passing behind the Sun, but don't worry—it never gets closer than about 150 million miles from Earth.
Scientists are excited because studying its makeup could reveal secrets about what's out there between the stars.