The BHs are there, and a big one (about 10^6-10^7 suns) is right at the center of our Milky Way galaxy, and another big one is at the center of Andromeda galaxy, and many of them in most of other big galaxies. Also there are several small BHs in our neigborhood (well, a couple thousand light years away),like Sygnus X-1 or A0620-00.

Due to distances, angular size of even accretion disc is so small that backyard telescope indeed does not see more than a companion star in case of small nearby BH or a bright haze containing millions of other stars in case of galactic BHs.

Even Hubble scope [coupled with a spectrometer] barely sees outer part of accretion discs of some huge galactic BHs [and opposite sides of discs are indeed blue and red shifted by extremely high orbital velocity - this is most compelling feature of a heavy black hole].

• Re: Re: Re: Finding Black Holes (BHs) - dbrown5511 - February 1, 2001 - 12:31 UTC
  • Re: Re: Re: Re: Finding Black Holes (BHs) - alexander - February 1, 2001 - 22:09 UTC