MoonfallBook - 1998
Debris from the destroyed Moon wreaks massive havoc on Earth -- leaving Haskell, who is still trapped aboard the shuttle, as President. But the ship is severely crippled. Help is on its way, but it may not reach them in time. Even worse, a fragment of moonrock massive enough to end civilization is roaring toward Earth. Now there's only one way to save the world from total destruction ... if Charlie Haskell is willing to be something even more important than President -- a hero.