: Hi, I'm doing this research on dark matter. My question is that is dark matter the samething as black hole? And how does gravity affect it? I also heard of a theory that the universe is expanding based on the calculations of gravitional hold. Is that true? What else is out there ? I'm looking forward in hearing from you. Thank you very much.

dark matter is not same as back hole....dark matter is matter in universe that must exist because stars on outer rim of galaxies are spinning around center of galaxy at same speed as stars near center of galaxy.....in order for this to happen, there must be tremedous amount of invisible matter to create the gravity to pull on these outer stars....nobody is sure what dark matter is, it may be neutrinos but scientists are not sure that neutrinos have mass....the universe is expanding based on observation....the hubble telescope is named after Edwin Hubble who discovered that the galaxies throughout the universe are speeding away from each other which indicates the universe is expanding.....also radiotelescopes can pick up background radiation from outer space that is leftover from the big bang.....the universe may continue expanding forever, or it may stop expanding and start contracting.....all depends on how much mass there is in universe.....right now it seems to be right on the line between contraction and eternal expansion

• Re: Question - Reed_Hoggan/">Reed Hoggan - February 6, 1998 - 21:36 UTC