The following information is from a wikipedia article discussing the concept of Hawking radiation.
Sound very cold to me. If you want to be mind numbed, read this article.

From;

http://en.wikipedia.org/wiki/Hawking_radiation

"a black hole of one solar mass other words, the mass of the sun has a temperature of only 60 nanokelvin; in fact, such a black hole would absorb far more cosmic microwave background radiation than it emits. A black hole of 4.5 × 1022 kg (about the mass of the Moon) would be in equilibrium at 2.7 kelvin, absorbing as much radiation as it emits"
Source(s):
http://en.wikipedia.org/wiki/Hawking_radiation

Permalink | Report

Yes, a black hole does generate heat but further explanation is required.

Black holes themselves are very cold as previous answerers have described, but the material falling into a black hole is extremely hot and releases X-rays which is one of the ways scientists find black holes.

Imagine some material in space around a black hole. It has a lot of gravitation energy because of the attraction of the black hole. As it falls toward the black that gravitation potential energy is converted into kinetic energy as it speeds up and is compressed. The friction between this material and other material falling into the black hole adds heat energy and eventually the material will emit this energy as light. At some point it gets so hot that it emits x-rays.

"In 1967 Soviet theoreticians had suggested that if a black hole were orbiting a larger, visible star, it would draw gases from the star. As those gases spiraled toward the black hole, they would collide, compress and heat up to as high as 100 million degrees—enough to produce an intense flow of X rays.

Recent (1973) findings by NASA'S new Copernicus earth satellite strongly support this scenario. Cygnus X-l shows a sharp decrease in X-ray emissions every 5.6 days. That, according to optical astronomers, seems to be the time it takes the bright star's unseen companion to make one trip around it. In other words, every 5.6 days the black hole passes behind the visible star. Thus, the supergiant partially blocks the X rays, resulting in the fluctuations observed on earth.

The combined calculations and observations add up to the best proof yet that a black hole has been found."
from http://www.time.com/time/magazine/article/0,9171,908291,00.html

To further your exploration of black holes science http://www.spaceref.com/tools/vi.html?cat=blackholes&id=139&imgs=movie has a illuminating explanation and animation on a spinning black hole. MIT has six lectures from their course Exploring Black Holes on Youtube where you can find even more details on black hole physics. http://www.youtube.com/watch?v=bFGiQEEvh18&feature=PlayList&p=858478F1EC364A2C&index=0&playnext=1
Source(s):
http://www.gothosenterprises.com/black_holes/outside_black_holes.html
http://imagine.gsfc.nasa.gov/docs/science/know_l2/black_holes.html

Permalink | Report