We're Not On Earth Anymore! - James a. Love - Bog

After an alien encounter in their local park, Tom and Pip embark on an epic space adventure when they are given a spaceship. They encounter alien civilizations, hunt dinosaurs, and are sucked through a wormhole. While lost in an even stranger part of space, Pip and Tom must rely on each other to avoid an evil empire and find another wormhole to get home.