Black hole jet erupts at near light speed

Posted by Kate Taylor

Astronomers have snapped a supersonic jet of material blasting over two million light years from the centre of a distant galaxy.

It looks strikingly similar to the afterburner flow of a fighter jet - except that, here, the jet engine is a supermassive black hole and the jet material is moving at nearly the speed of light. It was photographed using the CSIRO Australia Telescope Compact Array radio telescope in New South Wales.

Like a fighter jet exhaust, the galaxy-scale jet shows regularly-spaced bright and dark regions in a diamond shape, and it's possible that the pattern observed in the back hole jet is produced in the same way.

"Massive jets like this one have been studied for decades, since the beginning of radio astronomy, but we still don’t understand exactly how they are produced or what they’re made of," says Dr Leith Godfrey from the International Centre for Radio Astronomy Research.

"If the brighter patches are caused by the same process in astronomical jets as they are in earthly jet engines, then the distance between them can give us important information about the power of the jet and the density of the surrounding space."

Jets such are this are the largest objects in the universe, about 100 times larger than the Milky Way. They are extremely powerful, and are believed to stop stars forming in their parent galaxy, limiting how big the galaxies can grow and affecting how the universe looks today.

"This new image of the jet shows detail we’ve never seen before and the pattern we revealed provides a clue to how jets like this one work," says Dr Jim Lovell, a co-author from the University of Tasmania.

"This particular jet emits a lot of x-rays, which is hard to explain with our current models. Our new find is a step forward in understanding how these giant objects emit so much x-ray radiation, and indirectly, will help us understand how the jet came to be."