Aftermath
Trust no one. The Remnants are outsiders on the planet they once called Home. 500 years after the Rock, Earth is an arid wasteland, inhabited only by a handful of human descendants & mutated animals. To survive, they must plant one of their own -- Mo'Steel -- as leader of a wild band of surface-dwelling Marauders. But first he has to prove himself by defeating the Beasts, defending the group from Slizzer attacks, and somehow safely leading the Marauders to The Source. And if that’s not enough -- he has to keep an eye on those closest to him. . . . because he no longer knows who his friends are.

Back-of-Book Summary:
Earth has definitely changed since the Rock hit it 500 years ago. The world doesn't even revolve anymore. On one side: an unbearably hot, arid, unyielding desert with boiling seas and no relief. On the other: a vast, pock-marked plain of freezing-cold eternal darkness. The Remnants are trapped in a narrow strip between the two deadly plains, with nowhere else to go.
But there is more to this devastated Earth than meets the Remnants' eyes. There are people underground. Humans. And they've been watching Jobs and the others' every move. Now the question is: Will Earth's current inhabitants accept those from the past? Or will the Remnants become as extinct as the planet they once knew?
Juvenile fiction, Asteroid, Apocalypse, Survival, Aliens
K.A. Applegate