The interstellar comet 3I/ATLAS made its closest approach to Earth today (Dec. 19, 2025). Here's the latest news you need to ...

The livestream will now begin Friday at 11 p.m. EST, Dec. 19 (0400 GMT on Dec. 20), weather permitting, after rain prevented ...

The mystifying 3I/ATLAS interstellar comet is blazing toward Earth and will soon come as close to our planet as it ever will.

Looking for a sky event this week? Check out our full Sky This Week column. December 19: Visit Triangulum Jupiter's innermost Galilean moon, Io, crosses the gas giant along with its shadow this ...

A quiet messenger from the farthest reaches of the Milky Way is making its last, dramatic appearance on this day, December 19, 2025. The interstellar comet 3I/ATLAS, which is a frozen remnant from the ...

T he three Norths are moving on from their "historic" meet-up in England. After momentarily aligning over Britain for three ...