The Coolest Star in the Galaxy is No Warmer Than a Cup of Hot Coffee

Illustration: L. Calçada, ESO

When you think of stars, do you think a hot ball of plasma in space? (I mean, our own Sun has a surface temperature of approximately 5,800 K). Well, not all stars are hot: a newly discovered star 75 light-years away from us is no warmer than a cup of coffee.

Dubbed CFBDSIR 1458 10b, the star is what’s called a brown dwarf. These oddball objects are often called failed stars, because they have starlike heat and chemical properties but don’t have enough mass for the crush of gravity to ignite nuclear fusion at their cores.
With surface temperatures hovering around 206 degrees F (97 degrees C), the newfound star is the coldest brown dwarf seen to date.

Full Story