Three scientists have won the 2020 Nobel Prize in physics for their discoveries related to massive objects called black holes.

The Royal Swedish Academy of Science said Tuesday it will give half of the $1.1 million prize to Roger Penrose of Britain's University of Oxford. It is recognizing his use of mathematics to prove that black holes are a direct result of "Albert Einstein's general theory of relativity."

Germany's Reinhard Genzel and Andrea Ghez of the United States will share the other half of the physics prize. Genzel works at both the Max Planck Institute in Germany and the University of California, Berkeley. Ghez is a professor in the Department of Physics and Astronomy with the University of California, Los Angeles.

The academy is recognizing the two scientists "for the discovery of a supermassive compact object at the center of our galaxy." That object was a large black hole.

What are black holes?

The physics prize celebrates what the Nobel Committee called "one of the most exotic objects in the universe."

Black holes might exist at the center of every galaxy. Galaxies are huge systems that contain billions of stars. Smaller black holes can be found around the universe. Nothing, not even light, can escape their gravity. Time comes to a halt as it gets closer.

"Black holes, because they are so hard to understand, is what makes them so appealing," Ghez told The Associated Press. "I really think of science as a big, giant puzzle."

"You get this mixing of space and time," she said, adding that is what makes black holes so hard to understand.

Penrose proved with math that the formation of black holes was possible. His work was based heavily on Einstein's general theory of relativity.

"Einstein did not himself believe that black holes really exist, these super-heavyweight monsters that capture everything that enters them," the Nobel Committee said. "Nothing can escape, not even light."

British astronomer Martin Rees noted that Penrose's work fueled a "renaissance" in the study of relativity in the 1960s. He added that Penrose, together with a young Stephen Hawking, helped support evidence for the Big Bang and black holes.

"Penrose and Hawking are the two individuals who have done more than anyone else since Einstein to deepen our knowledge of gravity," Rees said.

Nobel prizes are only awarded to the living. Hawking died in 2018.

Finding ‘an extremely heavy, invisible object'

In the 1990s, Genzel and Ghez were each leading a group of astronomers. Both groups were interested in the center of our Milky Way galaxy. They both found that there was "an extremely heavy, invisible object" that pulls other stars, causing them to move around at high speeds, the committee said.

It was a supermassive black hole 4 million times the mass of our sun.

The first picture Ghez got of the object was in 1995. The image came from telescopes at the W.M. Keck Observatory, which had just gone online. A year later, another picture appeared to show that the stars near the center of the Milky Way were moving around something. A third picture led Ghez and Genzel to think they had discovered something.

Now scientists know that all galaxies have supermassive black holes.

"Today we accept these objects are critical to the building blocks of the universe," Ghez said.

Ghez is the fourth woman to be awarded the Nobel Prize for physics. The others were Marie Curie in 1903, Maria Goeppert-Mayer in 1963, and Donna Strickland in 2018.

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Words in This Story

compact – adj. smaller than other things of the same kind

exotic – adj. very different, strange or unusual

puzzle – n. something that is difficult to understand; a game with many pieces that have to be put together to form a picture

monster – n. a powerful and large thing that cannot be controlled

renaissance – n. a period of time when there is new interest in something that has not been popular for a long time

big bang – n. a huge explosion that might have happened when the universe began

invisible – adj. not possible to see, hidden from sight