Astronomer discovers ice-cold star neighbor

By Casey Frye, CCNN Writer

brown dwarf
A size comparison showing how big a brown dwarf star is.

Our Sun might blaze with cosmic heat, but an astronomer recently discovered a neighboring star that’s super frosty! The chilly orb is classified as a brown dwarf star, meaning it’s a star-like object bigger than planets, but not huge enough to keep an infinite fire burning like the Sun.

The discovery was made possible by the Wide-field Infrared Survey Explorer (WISE), and the star’s incredibly long name is WISE J088510.83-07144.25 (so let’s call it WISE J0 for short).

WISE J0 is “just” 7.2 light-years from Earth, so it would take light (which travels at about 671 million miles per hour) roughly 7.2 years to reach the distant star. Whoa! That may seem super far away, but it’s apparently close enough to make WISE J0 the 7th closest known star to the Sun. It’s also a chilly 9 degrees Fahrenheit, which is literally colder than ice.

The faint red star was hard to spot, but astronomer Kevin Luhman is a brown dwarf expert and was able to identify the dim object’s movement over the course of a few years. Even though stars speed through space at hundreds of kilometers a second, it can take centuries before we notice them move even a little, due to our faraway perspective on Earth. However, WISE J0 moved pretty fast over the course of several months, meaning it was way closer than most.

Images courtesy of NASA.