Record-Breaking Star Near Black Hole

The update

Astronomers have identified a star that holds the record for being the closest known object to the Milky Way’s supermassive black hole, Sagittarius A*. The star, designated S301, was found by the GRAVITY+ collaboration using the European Southern Observatory’s Very Large Telescope Interferometer. It is also the fastest-moving star in the galaxy, traveling at top speeds of about 25,000 kilometers per second, or roughly 8 percent the speed of light.

Why it matters

The star’s extreme location and velocity make it a unique laboratory for testing general relativity. Because it passes so close to the black hole, the star’s orbit is expected to warp in a specific way depending on the spin of Sagittarius A*. Measuring this warp could reveal the black hole’s spin, a characteristic that is notoriously difficult to observe directly. This measurement provides a critical test of Einstein’s theory of general relativity in extreme gravitational environments.

What to watch

Future observations should focus on tracking the star’s orbital precession over time. Confirming this specific warping pattern would validate our current understanding of black hole physics or point to new phenomena in extreme gravitational settings.

Sources

• sciencenews.org — Star designation (S301), discovery team (GRAVITY+), speed (25,000 km/s), and the potential to measure black hole spin.
• livescience.com — Context on the harsh environment near Sagittarius A* and the broader study of galactic centers.