event horizon

American  

noun

Astronomy.

1. the boundary around a black hole on and within which no matter or radiation can escape.

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event horizon British  

noun

1. astronomy the surface around a black hole enclosing the space from which electromagnetic radiation cannot escape due to gravitational attraction. For a non-rotating black hole, the radius is proportional to the mass of the black hole

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event horizon Scientific  

/ ĭ-vĕnt′ /

1. A spatial boundary around a black hole inside which gravity is strong enough to prevent all matter and radiation from escaping. The inability of even light to escape this region is what gives black holes their name.

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Etymology

Origin of event horizon

First recorded in 1970–75

Example Sentences

"Synthetic aperture imaging -- the method that allowed the Event Horizon Telescope to image a black hole -- works by coherently combining measurements from multiple separated sensors to simulate a much larger imaging aperture."

From Science Daily

In 1971, Stephen Hawking proposed that a black hole's event horizon, its outer boundary where neither light nor matter can escape, cannot shrink.

From Science Daily

"As long as the matter is still rotating outside the event horizon -- before being inevitably pulled in -- it can emit final signals of light that we can, in principle, detect."

From Science Daily

It predicts the existence of black holes and the event horizon, a boundary beyond which nothing -- not even light -- can escape.

From Science Daily

“No matter how much compliments, no matter how much adoration — whatever people were throwing my way — as soon as it went past the event horizon and into me, it was a black hole where it just disappeared. Nothing stuck and I didn’t feel good about myself,” Hammer said on the podcast.

From Los Angeles Times