Black holes. You have heard about them, but what are they really? Even scientists have a difficult time understanding these huge space phenomena.
Black holes act like gigantic vacuum cleaners in the middle of our galaxy, the Milky Way. They pull everything and anything into their center. Nothing escapes them, not even light. For something that is relatively small in the universe (a black hole), to pull whole galaxies into it, this “thing” must have a bigger gravitational pull than the enormous galaxies. And what can be bigger than a galaxy? An even bigger galaxy? Nobody has visited a black hole of course, so we cannot be sure, but there are some hypotheses – clever guesses – among scientists.
All ideas about black holes build on the theory of general relativity, which predicts that a very compact mass (enormous amounts of “stuff”, or matter) will deform space-time to form a black hole where absolutely everything collapses into. More simply put, an old star for example, which has burnt out, may not have enough energy left any more to hold its own huge mass up. It collapses onto itself and creates a black hole.
The general theory of relativity was published by Albert Einstein in 1915 – very soon 100 years ago! More exact ideas of what black holes are, however, took until the 1960’s before scientists come up with.
What do you think best describes a black hole is?
Please vote.
By George G