Star gorge burps from black hole

It's a globular star cluster and is known as 47 Tucanae. But is anybody out there? Picture / AP, Nasa.

"For an analogy, astronomers often refer to black holes as 'eating' stars and gas. Apparently, black holes can also burp after their meal," Eric Schlegel of the University of Texas said in a statement put out by Nasa.

Schlegel is the lead author of a new study on these cosmic belches, which was presented on Wednesday at the annual meeting of the American Astronomical Society.

These blasts of matter that black holes expel, which scientists believe help regulate the size of the holes and create new stars, can be hard to catch.

It was only in late November that a research group claimed to have caught the entire process, belch included.

"Our observation is important because this behaviour would likely happen very often in the early universe, altering the evolution of galaxies," Schlegel said.

The black hole studied in November was 300 million light years away, but the super-massive black hole observed by Schlegel and his colleagues is just 26 million light years away in the Messier 51 galaxy system.

The black hole sits in the centre of a small spiral galaxy that's working on merging with a second, larger spiral galaxy. It's likely that this cohabitation gave the black hole some gaseous material to chow down.

Using Nasa's Chandra X-ray Observatory, the researchers spotted twin arcs of X-ray emissions from the black hole in question, which they believe to be the after-effects of a big meal that happened millions of years ago.

They also noted a burst of colder hydrogen gas in the trajectory of the jets, suggesting that the hot burp had "snow ploughed" other gases into shape on its way out into the galaxy.

Meanwhile, researchers have found you can observe a nearby, active black hole with a 20cm telescope.

As material from surrounding space falls into them, violent bursts of light are released - which can be seen.

"We now know that we can make observations based on optical rays ... and that black holes can be observed without high-spec X-ray or gamma-ray telescopes," lead author Mariko Kimura, a master's student at Kyoto University, said.

Washington Post - Bloomberg, Daily Mail