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Study spots black hole shredding star

University astronomers have helped to gather evidence of a supermassive black hole shredding a star.

Supermassive black holes, weighing millions to billions times as much as the Sun, lurk in the centres of most galaxies.

These lie quietly until an object, such as a star, wanders close enough to get ripped apart by their powerful gravitational forces.

Astronomers have spotted these stellar events before, but this is the first time they have been able identify the victim.

Telescope study

Using a slew of ground- and space-based telescopes, a team of astronomers has identified the victim as a star rich in helium gas.

The star came from a galaxy 2.7 billion light-years away.

Researchers say that when the star was ripped apart by the gravitational forces of the black hole, some of its remains fell into the black hole, while the rest was ejected at high speeds.

A glow can be seen from the stellar gas falling into the black hole over time.

This observation yields insights about the harsh environment around black holes and the types of stars swirling around them.

The study, led by The Johns Hopkins University in Baltimore and including researchers from the Universities of Edinburgh, Durham and Belfast, is published in Nature.

Rare encounter

Astronomers have predicted that stripped stars circle the central black hole of our Milky Way galaxy.

These close encounters, however, are rare, occurring roughly every 100,000 years.

Astronomers monitored hundreds of thousands of galaxies with the Pan-STARRS1 telescope on Mount Haleakala, Hawaii.

This telescope scans the entire night sky for all kinds of transient phenomena, including supernovae and Near Earth Asteroids, as well as star-shredding events.

Pan-STARRS was built by astronomers in Hawaii, and is operated by an international consortium, including the astronomers from Edinburgh, Durham, and Belfast.

As the object faded, it stayed hot, so we knew it wasn’t a supernova – they cool down.

Professor Andy LawrenceSchool of Physics and Astronomy