Re: Black Holes
to | tenchi@usagi.jrd.dec.com
|
from | "Animantoric (Jeremy)" <animantoric@geocities.com>
|
subject | Re: Black Holes
|
date | Tue, 02 Dec 1997 20:35:17
|
At 10:48 AM 12/2/97 -0700, you wrote:
>Here are the definitions of black holes from NASA (if you are not
>interested stop reading now):
>
>Micro-Black Holes
>
>Formation
> Possibly formed in small regions of high density during the first
>few seconds of the Big Bang.
^
If it actually happened--|
>Unusual Features
> Micro-black holes aren't so black! Quantum mechanics and
>thermodynamics tell us that they should radiate all forms of energy due
>to the strongly varying gravitational fields just outside their event
>horizon. These black holes slowly radiate themselves away, finally
>disappearing in a flash of high-energy radiation.
Yeah right...
>Size
> If a micro-black hole is created with a mass of greater than 10^17
>grams, it would still be around today. This mass corresponds to about a
>cubic kilometer of water. In terms of size, it would be smaller than an
>electron!
If it is ultimately compressed, it has no size...
>Observations
> Once believed to be a possible source of gamma-ray bursts, there is
>no current observational evidence for their existence.
>
>Stellar-Mass Black Holes
>
>Formation
> When a star with a mass of greater than 10 times the mass of the
>Sun explodes in a supernova, the central core left behind will collapse
>into a black hole.
>Unusual Features
> When this type of black hole is part of a binary system, matter can
>sometimes stream from the other star into a disk surrounding the black
>hole. This is called an accretion disk.
I've seen pics of this...
>Size
> These black holes would range from about 5 to 100 times the mass of
>the Sun, giving them diameters of 20 to 400 miles.
Same as above...
>Observations
> At present, there are over 25 objects astronomers suspect may be
>black holes near or in our own galaxy. A partial list: Cygnus X-1,
>A0620-00, V404 Cygni, LMC X-1, LMC X-3
>
>Super-Massive Black Holes
>
>Formation
> Formed via accretion from smaller bodies in the centers of many
>galaxies.
>Unusual Features
> On this scale, some of the infalling matter may become redirected
>into jets and ejected over the poles of the black holes. This phenomenon
>may explain the radio jets observed from the centers of some galaxies.
>Size
> HUGE! One million to one billion times the mass of the Sun. They
>would be about the size of our solar system.
Har har...same as above!
>Observations
> Active Galactic Nuclei (AGN), Seyfert Galaxies, Quasars.
>
>If this is not enough information for you, you can go to the site:
>
> http://www.geocities.com/Area51/Cavern/6910/high-crusade.html
>
>and page down to the NASA search engine, and enter the words "black
>holes" (without quotes). You will even find articles about the Hubble
>telescope's evidence of the existance of black holes.
Interesting, but maybe they should actually go talk to some physicists...
-----------------------------------------------
The Animantoric...
Anime crazy!
Tenchi Muyo!
Long live Ryoko!
"Is that a sign of affection, or do you just not
like me?"-Kagato
Visit my page at: http://www.geocities.com/Tokyo/Temple/2366
-----------------------------------------------
unauthorized access prohibited
MLtools V3.1 Copyright (c) Usagi Labs