A Ring of Light: What a Black Hole Actually Looks Like

A Ring of Light: What a Black Hole Actually Looks Like

Written by Oscar Scholin, Journalist

Since renowned physicist Albert Einstein published his much acclaimed theory of general relativity in 1915, the realm of physics has been attempting to prove many of Einstein’s equations and theories about the way the universe works correct. In his theory of general relativity, Einstein proposed that massive objects, such as planets, stars, and theoretically black holes, distort what he called “spacetime.” Einstein thought of spacetime as a fabric, such as a dining cloth, that could be warped by massive objects, such as an apple if the cloth was fully stretched out.

Because black holes are so incredibly dense, the immense force of gravity literally distorts and rips apart the fabric of spacetime. Scientists think that we can see the traces of this distortion through the path of photons (light particles) and thus determine what a black hole actually looks like.

To answer this call, Ph.D. student in astrophysics at MIT Sheperd Doeleman began the Event Horizon Telescope Collaboration in the mid-1990s with the main goal of photographing a black hole for the first time.

Up until early April 2019, the scientific community only had simulations of what they thought a black hole looked like. The black hole photographed was in Galaxy M87 — over 55 million light years away — and had the same mass of 6.5 billion suns compressed into the size of our solar system.

The light in the photograph is the orbit of photons, hot because of friction and warping. The light, as Einstein predicted more than 100 years ago, does indeed move around the puncture in space time and comes to Earth in parallel lines, which forms a ring-like image.

In order to see the light travelling from such a far distance, Doeleman and his team synchronized hundreds of telescopes from around the world to act as one super-telescope and be able to capture the image we now see.

The ring marks the event horizon, or “the point of no return.” Because no light or matter can escape from this point, the space there appears black, and hence the “black” hole. Doeleman explains that the significance of black holes is, “that’s where the quantum world and the gravitational world come together….that’s where all the forces become unified, because gravity finally is strong enough to compete with all the other forces.” Black holes will help in understanding Einstein’s concepts of astrophysics and the fundamental structure and laws that govern (and when those laws cease to govern) our universe.

The Milky Way, our own galaxy, has a black hole, too, except it is 1000 times less massive than the one photographed in galaxy M87. Perhaps, someday, our black hole will be photographed, once the conditions are right and we have telescopes that can see it.

But, in order to undertake that kind of project, we will need teamwork. And lots of it. Doeleman explains that his team consisted of 200 people from 60 institutes and 20 countries. “If you want to build a global telescope you need a global team,” explains Doeleman, “And this technique that we use of linking telescopes around the world kind of effortlessly sidesteps some of the issues that divide us.” Doeleman underscores one of the greatest elements about science: it has the incredible power to unite people of various religions, nationalities, and countries to further scientific understanding. In this manner, science has the unique ability to unify the world to solve problems for the greater good, such as global warming.

If your wish to watch a TED talk interview with Doeleman, click here: https://www.ted.com/talks/sheperd_doeleman_inside_the_black_hole_image_that_made_history?utm_campaign=tedspread&utm_medium=referral&utm_source=tedcomshare or watch a mesmerizing deep space zoom into the heart of galaxy M87 here: https://www.youtube.com/watch?v=19to087TYv8&feature=youtu.be