What Are Black Holes? - NASA
Sep 8, 2020 · A black hole is an astronomical object with a gravitational pull so strong that nothing, not even light, can escape it. A black hole’s “surface,” called its event horizon, defines the boundary where the velocity needed to escape exceeds the speed of …
Black hole - Wikipedia
A black hole is a region of spacetime wherein gravity is so strong that no matter or electromagnetic energy (e.g. light) can escape it. [2] Albert Einstein's theory of general relativity predicts that a sufficiently compact mass can deform spacetime to form a black hole. [3] [4] The boundary of no escape is called the event horizon.
Black Holes | Center for Astrophysics | Harvard & Smithsonian
Supermassive Black Holes are the monsters of the universe, living at the centers of nearly every galaxy. They range in mass from 100,000 to billions of times the mass of the Sun, far too massive to be born from a single star.
'Impossible' black holes discovered by the James Webb telescope …
Nov 22, 2024 · Hawking suggested that these black holes, which could be as small as asteroids, would slowly dissolve through so-called Hawking radiation and be visible in the present-day universe. Decades of ...
Black Holes - NASA Science
Black holes are among the most mysterious cosmic objects, much studied but not fully understood. These objects aren’t really holes. They’re huge concentrations of matter packed into very tiny spaces.
Stupendously large: The largest black holes in the Universe - BBC
Oct 7, 2024 · Almost every large galaxy has a supermassive black hole at its centre, but in the grand scheme of the Universe, ours – called Sagittarius A* – is a veritable featherweight. Over the past...
Black holes, explained by an astrophysicist - Astronomy Magazine
Dec 11, 2023 · A black hole is a region of universe where gravity is so outrageously strong that nothing, not even light, can escape. Once something enters a black hole by crossing an invisible boundary...
10 Questions You Might Have About Black Holes - NASA Science
Sep 23, 2019 · A black hole is an extremely dense object in space from which no light can escape. While black holes are mysterious and exotic, they are also a key consequence of how gravity works: When a lot of mass gets compressed into a small enough space, the resulting object rips the very fabric of space and time, becoming what is called a singularity.
How many black holes are there in the universe? | Space
Nov 16, 2021 · In a recent study, researchers determined that about 1% of all the "normal" (that is, not dark) matter in the universe is bound up inside black holes.
What is a black hole? | University of Chicago News
Black holes are regions in space where an enormous amount of mass is packed into a tiny volume. This creates a gravitational pull so strong that not even light can escape. They are created when giant stars collapse, and perhaps by other methods that are still unknown.