Three scientists have been awarded the 2020 Nobel Prize in Physics for work to understand black holes.
Roger Penrose, Reinhard Genzel and Andrea Ghez were announced as this year's winners at a news conference in Stockholm.
The winners will share the prize money of 10 million kronor (£864,200).
David Haviland, chair of the physics prize committee, said this year's award "celebrates one of the most exotic objects in the Universe".
Black holes are regions of space where gravity is so strong that not even light can escape from them.
UK-born physicist Sir Roger Penrose, from the University of Oxford, demonstrated that black holes were an inevitable consequence of Albert's Einstein's theory of general relativity.
He receives half of this year's prize, with the other half going to Genzel and Ghez. Prof Ghez is only the fourth woman to win the physics prize, out of more than 200 laureates since 1901.
The other female recipients are Marie Curie, Maria Goeppert-Mayer and Donna Strickland - who won in 2018.
"The history of black holes goes way back in time to the end of the 18th Century. Then, through Einstein's general relativity, we had the tools to describe these objects for real," said Ulf Danielsson, a member of the Nobel Committee.
But the mathematics of these objects was incredibly complex. Many researchers believed they were nothing more than mathematical artefacts, existing only on paper. It took researchers decades to realise that they could exist in the real world.
"That's what Roger Penrose did," said Danielsson. "He understood the mathematics, he introduced new tools and then could actually prove that this is a process you can naturally expect to happen - that a star collapses and turns into a black hole."
Sir Roger, he said, "laid the theoretical foundations to say: these objects exist. You can expect to find them if you go out and look for them".