In this picture book, a boy writes a letter to an imagined alien, explaining all the things he will need to know about Earth and the people who live here--and adding a postscript asking what the alien might look like.
Five thousand years later after a catastrophic event rendered the Earth a ticking time bomb, the progeny of a handful of outer space explorers--seven distinct races now three billion strong--embark on yet another audacious journey: to return to Earth.