Astronomers have discovered the fastest known star in the Milky Way orbiting the galaxy's central supermassive black hole [1].
This discovery provides scientists with a unique tool to measure the spin of Sagittarius A* and test theories of gravity in strong-field regimes [1]. By observing how the star behaves under extreme gravitational pressure, researchers can better understand the physics of the galactic center.
The star is a faint object located at the heart of the Milky Way [1]. It travels at a velocity of 15,500 miles per second [2], which is approximately 56 million miles per hour [3]. This speed makes it the fastest stellar object ever recorded within our galaxy [2].
Researchers led by a team observing the Galactic Center identified the object through its rapid orbit around Sagittarius A* [1]. The black hole's immense mass creates the gravitational pull necessary to accelerate the star to such extreme velocities [2].
Because the star moves so quickly and passes so close to the black hole, it acts as a probe. Scientists can use the star's trajectory to determine the black hole's rotation, and verify if Einstein's general relativity holds true in the most extreme environments of the universe [1].
“The star travels at a velocity of 15,500 miles per second.”
The identification of this high-velocity star allows astronomers to treat the stellar orbit as a natural laboratory. By calculating the precise path and speed of the object, scientists can map the spacetime curvature around Sagittarius A*, potentially revealing new data about black hole dynamics that were previously impossible to observe with slower-moving stars.
