If they were truly isolated, it's hard to imagine how they'd be detected, other than by gravitational lensing.Originally posted by taylordnz
are there any black holes found that have no companion stars or anything with them, are there any found?
if so could you please name a few on this thread
thanks
Originally posted by Nereid
If they were truly isolated, it's hard to imagine how they'd be detected, other than by gravitational lensing.
The one that best meets your criterion is the supermassive one at the centre of our Milky Way galaxy - we know it's there, how massive it is, etc, yet there are no accretion disks, jets, etc. Of course, if by 'companion stars' you mean stars orbiting about a BH, then we're such a companion (although there's an awful lot more mass than just the galactic BH which contributes to our motion).
This link gives you an idea of how 'alone' the Milky Way centre BH is:
http://www.eso.org/outreach/press-rel/pr-2002/pr-17-02.html
Correctomundo. See: http://casa.colorado.edu/~ajsh/hawk.html and notice the middle of the page about the (lack of) energy from the 3 billion Ms in the giant elliptical galaxy M-87. Also, much more back awhile at:Originally posted by Nereid
The Hawking radiation which stellar mass black holes emit, IIRC, is far less than what such a BH would emit just from absorption of stray ISM (inter-stellar medium) particles, and cosmic rays. For a giant BH like the one at the centre of the Milky Way, Hawking radiation would be undetectable, even from up close.
A black hole is a region in space where the gravitational pull is so strong that even light cannot escape it. It is created when a massive star dies and its core collapses, resulting in a singularity with infinite density and zero volume.
Black holes are formed when a massive star runs out of fuel and collapses under its own gravity. The core of the star becomes infinitely dense, creating a singularity which is surrounded by an event horizon - the point of no return.
It is currently believed that isolated black holes do exist, but they are difficult to detect as they do not emit any light. They could be formed from the merging of smaller black holes or through the collapse of a supermassive star.
Isolated black holes can be detected through their effect on surrounding matter and light. For example, scientists can observe the gravitational lensing effect - where light is bent around the black hole - or look for X-ray emissions from hot gas falling into the black hole.
No, isolated black holes do not pose a threat to Earth as they are too far away to have any significant effect on our planet. In fact, there are likely many isolated black holes in our galaxy that we are not aware of.