We have been taught since early childhood that stars are, how you say, hot. Damn hot. Scorch-you-to-a-crisp-then-leave-less-than-ashes kind of hot. But just because our own Sun has a surface temperature of 5,800 kelvin doesn’t mean that every star is that hot. Many are cooler, while others burn brighter and more hot than a hundred of our suns.
And then there is the sexily-named CFBDSIR 1458 10b, which is a brown dwarf star. For those of you playing at home, a “brown dwarf” is a star that… well, isn’t a star. It’s a star that has failed to achieve enough mass to ignite nuclear fusion. It is, for all intents and purposes, a failed star. CFBDSIR 1458 10b is now, it turns out, the single coolest star known to humankind with a surface temperature of 206 degrees.
That’s no hotter than a cup of fresh coffee. Accordng to University of Hawai’i professor Michael Liu, this is far and away the coldest star on record:
Over the years there has been steady but slow progress in pushing the boundaries of finding the coldest stars… But with this latest discovery we have made a big leap forwardóbesting the previous record holder by at least 150 Kelvin [270 degrees F, or 150 degrees C]
So, CFBDSIR 1458 10b, enjoy your title as “galaxy’s coldest star.” After all, you’ve… what? Scientists with NASA’s Spitzer Space Telescope think they may have found one that’s only 86-degrees fahrenheit?