Astronomers using the powerful ALMA telescope in Chile have spotted molecular activity in comet C/2014 UN271 (Bernardinelli-Bernstein)—a frozen giant nearly 85 miles wide, making it the biggest active comet ever observed from the distant Oort Cloud.

What’s even more amazing? This icy traveler was more than 16 times farther from the Sun than Earth when it started to show signs of life. ALMA detected dramatic jets of carbon monoxide gas blasting from the comet’s core, like steam escaping from a cosmic kettle.

This is the first time scientists have directly seen what fuels a comet’s activity so far from the Sun, offering exciting clues about how these ancient space visitors behave in the dark, frigid reaches of our solar system.