Supermassive Black Hole Tears Apart Star for Its Diet

First Posted: Jul 23, 2015 11:43 AM EDT

Scientists may have uncovered new information about the diet of black holes. Using archival data from the Sloan Digital Sky Survey, a team of astronomers have discovered a gigantic black hole that's devouring a star in its vicinity.The researchers spotted this black hole by exploring the archive of the SDSS in preparation for a future X-ray satellite mission. The spectra, which is where light is dispersed across wavelengths, allowed researchers to deduce properties like composition and temperature.

While the scientists were looking at one of the objects with multiple spectra, they were struck by an extraordinary change in one of the objects. In this case, the researchers were examining a galaxy in the constellation of Cetus, which is located about 3.5 billion light-years away.

"Usually distant galaxies do not change significantly over an astronomer's lifetime, i.e. on a timescale of years or decades," said Andrea Merloni, one of the researchers, in a news release. "But this one showed a dramatic variation of its spectrum, as if the central black hole had switched on and off."

Supermassive black holes are at home in the nuclei of large galaxies all around us. Most astronomers believed that these black holes grew to such enormous sizes by feeding mostly on interstellar gas from their surroundings. This process takes place over a very long time period and is capable of turning a small black hole into a heavyweight monster after a heavy star explodes in its vicinity.

With that said, the researchers found that this black hole was actually eating a star itself. With an estimated mass of 100 million solar masses, this was the biggest black hole astronomers had seen caught in the act of tearing a star apart.

The findings reveal a bit more about what black holes "eat" and show how supermassive black holes grow so large in the first place.

The findings are published in the journal Monthly Notices of the Royal Astronomical Society.