|
|
The Question
(Submitted January 23, 1998)
I want to know how a black hole that is so small that it
is only 2 to 3 kilometers big can pull an entire star into
its crevice.
The Answer
How does a mouse eat an elephant? One bite at a time.
A black hole in a close orbit around a star can pull the top layers of the
star off the surface and down its own gravity well. Once the material
passes beyond the black hole's event horizon, it is gone, and more stuff
can be consumed by the black hole. You are left with a slightly larger
black hole, and a slightly less massive star, so the black hole can pull a
little more material off the star. This continues until the star is gone,
and the black hole's hunger is yet unabated.
David Palmer
for Ask a High-Energy Astronomer
|
