A new way to measure cosmic black holes

Supermassive black holes are the largest black holes, with masses that can exceed a billion Suns. Just this spring, the first-ever image of the supermassive black hole at the center of the Messier 87 galaxy was taken, and ...

How did supermassive black holes grow so fast?

Black holes in the early universe pose a bit of a problem. Based on observations from telescopes on Earth and in space, we know that some black holes grew to be a billion times the mass of the sun just one billion years after ...

How the U.S. hydrogen bomb secrets disappeared

Given a choice of items to lose on a train, a top-secret document detailing the newly developed hydrogen bomb should be on the bottom of the list. In January 1953, amid the Red Scare and the Korean War, that's exactly what ...

Heavyweight in the heart of the Abell 85 central galaxy

In space, black holes appear in different sizes and masses. The record is now held by a specimen in the Abell 85 cluster of galaxies, where an ultra-massive black hole with 40 billion times the mass of our sun sits in the ...

Black hole or newborn stars? SOFIA finds galactic puzzle

Universities Space Research Association (USRA) today announced that scientists on NASA's Stratospheric Observatory for Infrared Astronomy (SOFIA) found a strange black hole that is changing its galactic surroundings in a ...

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Black hole

In general relativity, a black hole is a region of space in which the gravitational field is so powerful that nothing, including light, can escape its pull. The black hole has a one-way surface, called an event horizon, into which objects can fall, but out of which nothing can come. It is called "black" because it absorbs all the light that hits it, reflecting nothing, just like a perfect blackbody in thermodynamics. Quantum analysis of black holes shows them to possess a temperature and Hawking radiation.

Despite its invisible interior, a black hole can reveal its presence through interaction with other matter. A black hole can be inferred by tracking the movement of a group of stars that orbit a region in space which looks empty. Alternatively, one can see gas falling into a relatively small black hole, from a companion star. This gas spirals inward, heating up to very high temperature and emitting large amounts of radiation that can be detected from earthbound and earth-orbiting telescopes. Such observations have resulted in the scientific consensus that, barring a breakdown in our understanding of nature, black holes do exist in our universe.

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