Hawaii’s W. M. Keck Observatory (pictured surveying the Milky Way) helped astronomers identify S0-102.
Photograph courtesy Ethan Tweedie Photography


Speedy Star Found Near Black Hole May Test Einstein Theory

Discovery offers chance to study theory of relativity on grand scale.

Marc Kaufman
for National Geographic News
Published October 4, 2012

A star has been discovered speeding closely around the massive black hole at the center of the Milky Way, a new study says. The finding offers the tantalizing possibility of testing Einstein’s general theory of relativity on the grandest of scales.

The faint star, called S0-102, orbits the black hole in 11.2 years, making it the closest large object known in the vicinity of our galaxy’s superdense center. The star travels at speeds of up to 6,600 miles (10,600 kilometers) per second and is in a stable, if changeable, orbit.

S0-102 is only the second star identified as being in short orbit around the Milky Way’s black hole—the other, S0-2, takes about 16 years.

“The fact that we are finding stars this close to the supermassive black hole—a hundred times closer to its event horizon than ever identified before—shows just how fast this field is developing,” said study co-author Andrea Ghez, an astrophysicist at the University of California, Los Angeles. An event horizon is a boundary beyond which nothing, including light, can escape from a black hole.

“Our first goal has been to make the discoveries. But the next layer of science is the fundamental physics because this is an unparalleled laboratory for testing the general theory of relativity.”

Read more: Speedy Star Found Near Black Hole May Test Einstein Theory — National Geographic.

Home           Top of page