Exploring Black Holes

Credit: NRAO/AUI/National Science Foundation; S. Dagnello

Black holes have long captured the imagination, from groundbreaking ideas in Albert Einstein’s theory of general relativity to the first image of a black hole, revealed a century later by the global Event Horizon Telescope.  On this site, explore the nature of black holes, read the latest news about black hole research, and download a wide range of educational materials, images and videos of the universe’s most extreme objects.

All Sag A* multimedia — including new images, video content and a b-roll package is available for download on the EHT page.

Credit: NRAO/AUI/NSF; D. Berry/Skyworks

What is a black hole?

What is a black hole?

Black holes are extremely dense pockets of matter, objects of such incredible mass and miniscule volume that they drastically warp the fabric of space-time. Anything that passes too close, from a wandering star to a photon of light, gets captured. Most black holes are the condensed remnants of a massive star, the collapsed core that remains following an explosive supernova. However, the black hole family tree has several branches, from tiny structures on par with a human cell to enormous giants billions of times more massive than our sun.