What is a black hole?

A black hole is an invisible region of space that is thought to have such intense gravity that not even light can escape. Scientists believe that a black hole is created when a giant star collapses in upon itself as it dies. A star lives as long as it can burn fuel. The burning of fuel acts as a counterforce against gravity; without that counterforce, a star's gravity would cause it to collapse in on itself. So when that fuel runs out, gravity takes over and crushes the star. If the star is large enough and has a strong enough force of gravity, it will become a black hole when it collapses. Scientists have discovered evidence of several black holes in our galaxy, and they believe there may be millions more that have not been identified.


This is a web preview of the "Handy Answer Book" app. Many features only work on your mobile device. If you like what you see, we hope you will consider buying. Get the App