[gmku]

Someday the sun will explode, too. Then where will we be?

The moon is going farther away from the earth every year. When it gets so far away that it flies out of the earth's gravitational pull, the earth will wobble and there will be catastrophic weather and flooding that will wipe out everything.

Also, a large meteor could cause a huge catastrophe any day, if it hit the earth. The earth would be blanketed in an atmosphere so thick with dust that the sun could not penetrate for years and everything would freeze. This could happen anytime.