If a sun-like star were to approach within about 93 million miles of the Milky Way's central black hole, it would in essence become a spaghetti-like streamer of gas destined to vanish into the black hole, says Avi Loeb, chairman of the astronomy department at Harvard University.
The short-period stars among them represent a bonanza for several reasons. First, one complete orbit occurs within a span of time that falls well within the length of a career in astronomy.
Beyond the attraction of getting results before getting a gold watch, the discovery could represent the first in a larger population of dim stars at the galactic center.
The star at the center of Friday's report, dubbed S0-102, is substantially dimmer than the star with the 16-year period, dubbed S0-2. In the rest of the galaxy, faint stars outnumber bright stars, so detecting such a dim star in this region "opens the door to detecting many more in that environment, if they exist," he says, allowing for increasingly precise tests of general relativity, Dr. Loeb suggests.
The effects related to general relativity can be seen in the impact supermassive black holes have on the stars' orbits as they make their closest approach, he adds.
Like Earth orbiting the sun, stars do not travel around black holes in circles, but ellipses – meaning they are sometimes closer and sometimes farther away. But instead of tracing the same elliptical orbit repeatedly, as the Earth does around the sun, the elliptical orbits of short-period stars should shift with time, tracing a rosette pattern around the behemoth.