Astronomers have identified the fastest known star in the Milky Way, a stellar sprinter racing around the supermassive black hole that sits at the center of our galaxy. The discovery adds a striking new record to the catalogue of objects swirling through one of the most extreme environments known to science.
The star has been named S301, and it was found whipping around Sagittarius A star, the supermassive black hole at the heart of the Milky Way. It joins a family of stars, known as the S stars, that trace tight orbits close to the galactic center.
Its speed is difficult to grasp. At its closest approach, S301 is moving at roughly 15,534 miles per second. To put that in perspective, that is about 100,000 times faster than a commercial airplane, a pace that makes it the quickest star yet measured in the galaxy.
S301 is not only the fastest-moving member of its class but also the closest to the black hole that astronomers have found. Travelling at such an extraordinary velocity, the star completes a full loop around Sagittarius A star in only about 8.7 years.
For the researchers, though, the most important part of the discovery is not the raw speed but the star's extreme closeness to the black hole. That proximity places S301 in one of the most intense gravitational settings known anywhere in the universe.
That combination turns the star into a natural laboratory. Scientists say S301 will help them study some of the most extreme effects predicted by physics near a supermassive black hole, offering a rare chance to test the theory of general relativity where gravity is at its strongest.
By tracking stars like S301 as they swing past Sagittarius A star, astronomers can probe the environment around the galactic center in ever finer detail. Each new record-holder sharpens the picture of how matter and light behave under conditions that cannot be reproduced anywhere on Earth.