A newly discovered rogue stellar body may well be a "failed star," but it certainly isn't a failure when it comes to velocity!
The potential brown dwarf is racing through our Milky Way galaxy at 1.2 million mph (1.9 million kph). That's about 1,500 times faster than the speed of sound! Thankfully, this cosmic runaway is heading toward the center of the Milky Way and not toward us. However, the object is traveling so fast that it could eventually escape our galaxy entirely.
