Astronomical black holes are compact astrophysical systems characterized by regions of spacetime where gravity is so strong that no matter or radiation can escape beyond the event horizon. They are described by solutions to Einstein’s field equations, typically approximated by the Kerr or Schwarzschild metrics, and are defined by mass, spin, and (negligible) charge. Formed primarily via stellar core collapse or hierarchical mergers, they interact with their environments through accretion disks, relativistic jets, and gravitational-wave emission. Astronomical black holes span stellar-mass to supermassive regimes, influencing galactic dynamics, high-energy radiation processes, and cosmological structure formation.
There's a universe full of black holes out there, spinning merrily away—some fast, others more slowly. A recent survey of supermassive black holes reveals that their spin rates reveal something about their formation history.
Astronomy
Jan 21, 2025
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Active galactic nuclei are supermassive black holes at the center of certain galaxies. As matter falls into these black holes, enormous amounts of energy are released, making active galactic nuclei, or AGN, one of the most ...
Astronomy
Jan 17, 2025
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Researchers from the University of Connecticut have created the first 3D maps of star-forming gas clouds in one of the most extreme environments in our galaxy, and have studied previous flaring events from our galaxy's supermassive ...
Astronomy
Jan 15, 2025
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In December 2022, less than six months after commencing science operations, NASA's James Webb Space Telescope revealed something never seen before: numerous red objects that appear small in the sky, which scientists soon ...
Astronomy
Jan 14, 2025
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International teams of astronomers monitoring a supermassive black hole in the heart of a distant galaxy have detected features never seen before using data from NASA missions and other facilities. The features include the ...
Astronomy
Jan 13, 2025
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The night sky has always played a crucial role in navigation, from early ocean crossings to modern GPS. Besides stars, the United States Navy uses quasars as beacons. Quasars are distant galaxies with supermassive black holes, ...
Astronomy
Jan 13, 2025
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One supermassive black hole has kept astronomers glued to their scopes for the last several years. First came a surprise disappearance, and now, a precarious spinning act.
Astronomy
Jan 13, 2025
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Black hole quantum effects are usually thought to be too small to have any observable signatures. This is indeed the case for heavy black holes, such as the ones detected via gravitational waves by LIGO in 2015. These black ...
Of all the unanswered questions in modern science, perhaps the most talked about is whether we are alone in the universe. A new paper looks at another way we might be able to detect advanced civilizations, and at its center ...
Astronomy
Jan 8, 2025
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The size and spin of black holes can reveal important information about how and where they formed, according to new research.
Astronomy
Jan 7, 2025
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