After spinning around a black hole, matter simply falls straight in

The physics surrounding black holes is just plain weird. A gravitational well so strong that not even light can escape can do some pretty strange things to normal matter. Over the decades, many theories have been put forward as to what those strange things could be. And now, a new study by physicists at the University of Oxford has proved that, once again, Einstein’s theory of gravity was right.

Their work focused on a “submerged region” just outside the black hole’s radius. In this region, matter “sinks” straight into the black hole rather than orbiting it via the more familiar laws of orbital mechanics. One of the authors of the paper, Dr. Andrew Mummery, likens it to watching a river turn into a waterfall. The material flows nicely along a well-defined path and then seemingly falls off a cliff.

Theoretical work has been ongoing on this region for decades. The idea of ​​diving originally came from Einstein’s theory of gravity. He noted that close enough to a black hole, matter would be forced into the black hole at close to the speed of light. However, no one had yet collected any data and proved this theory.

However, data from NASA’s Nuclear Spectroscopic Telescope Array (NuSTAR) and the Neutron Star Interior Composition Explorer (NICER) change that. They collected X-ray data on a relatively small black hole located in a star system about 10,000 light-years away. This data showed that matter (which is all plasma at that point) moves rapidly towards the interior of the black hole once it reaches a certain threshold.

This discovery is just the first step in a long-term plan where researchers hope to use a much larger telescope to study much larger black holes. The Africa Millimeter Telescope is a proposed new ground-based telescope scheduled to begin operation in Namibia. Originally proposed in 2016, the project is slowly moving towards the first light and has so far received 10 million euros in funding.

With this new telescope, Oxford physicists hope to see one of the supermassive black holes at the center of our galaxy. They could potentially even capture a video of it spinning — or at least the matter around it spinning. This would be a first for black hole astronomy and a major technical achievement in itself.

Currently, many other smaller black holes can be analyzed using data from existing telescopes, such as NuSTAR and NICER, as well as other platforms. The paper also analyzed data from the International Space Station. With new tools and a better understanding of what to look for, there are undoubtedly more discoveries waiting to be made about black holes in the data we’ve already collected.

Learn more:
University of Oxford – First evidence that ‘submersible regions’ exist around black holes in space
Mummery et al – Continuous emission from within the submergence region of black hole discs
UT – New image reveals magnetic fields around our galaxy’s supermassive black hole
UT – Black Hole event horizons can become so large that they boggle your imagination

Main image:
An artist’s illustration of a black hole.
Credit – NASA