Astronomers may have detected a ‘dark’ free-floating black hole

Re:Astronomers may have detected a ‘dark’ free-floating blac... by uplifter on Thursday June 16, 2022 @02:09AM (#31762910)

Hawking radiation. A black hole emits hawking radiation at a wavelength about equal to its diameter, and with power (ie energy/time) inversely proportional to its diameter. So the smaller the black hole, the higher the energy of the photons it emits and also the more energy it emits per second. A black hole with the mass of Mount Everest (~10^14 kg) would, according to a hawking radiation calculator[0], have a schwarzschild radius of 10^-23m, and a proportional wavelength on the order of extremely intense gamma rays or cosmic rays, with a temperature of a billion degrees kelvin. Low-mass black holes aren't black at all.

[0] Online hawking radiation counter: https://www.vttoth.com/CMS/physics-notes/311-hawking-radiati...

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Re:Astronomers may have detected a ‘dark’ free-floating blac... by simiones on Thursday June 16, 2022 @04:24AM (#31763671)

It's important to note that Hawking Radiation is not a confirmed phenomenon, and unless we actually find such a small black hole, it will never be confirmed (stellar mass black holes are too cold compared to the microwave background to emit Hawking radiation, and will continue being so for an extraordinarily long time.

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