There Are Infinite Rings of Light Around Black Holes. Here's How We Could See Them

[Judi Lynn]

Artist's impression of photons veering around a black hole. (Nicolle R. Fuller/NSF)

MICHELLE STARR 19 MARCH 2020

A year ago, history was made. The long, painstaking work of scientists around the globe produced the very first direct image of the event horizon of a black hole, a supermassive monster called M87* 55 million light-years away. That glorious, golden, blurry image confirmed many of our ideas about black holes.

But the science didn't stop when the image came in. A team of scientists has now performed calculations based on what we learnt from M87* combined with the predictions of general relativity, to further predict how one day we could see this objects in much closer detail.

Black holes are incredibly gravitationally intense. Not only are they so massive that even light speed is too slow to achieve escape velocity against their gravitational pull, they also bend the path of passing light around them, beyond the event horizon.

If a passing photon is a bit too close, it will get trapped in orbit around the black hole. This creates what is called a "photon ring" or "photon sphere", a perfect ring of light predicted to surround the black hole, inside the inner rim of the accretion disc, but outside the event horizon.

More:
https://www.sciencealert.com/sending-telescopes-to-space-could-reveal-the-infinite-rings-around-a-black-hole

[shenmue]

1. Wow