While peering deep into the heart of the galaxy, astronomers have found the fastest star ever seen. This thing is tearing through space; at one point in its orbit, it’s moving at a terrifying 24,000 kilometers per second — over 85 million kilometers per hour!
That’s 8% the speed of light.
Holy relativistic acceleration! How can any star be screaming through space that quickly?
Well, it helps to plunge down to within 1.9 billion kilometers of a supermassive black hole.
Oh yeah, there’s a story here.
In the center of our galaxy, the Milky Way, is an enormous black hole with a mass four million times that of the Sun. All big galaxies have one.
This black hole, called Sgr A* (literally, “Sagittarius A-star”) isn’t alone. Surrounding it are a variety of objects, including dozens of massive stars. These orbit the black hole pretty close in, and the enormous gravity of the black hole swings them around at fiercely high velocity. The move so rapidly that changes in their positions can be seen over a matter of mere months.
Not that it’s easy to see that. We’re about 27,000 light years from the Milky Way’s center, so even though these ...