Between Planets

Between Planets is a 1951 science fiction novel by Robert Heinlein about an earth boy who leaves his ranch school on Earth to be with his scientist parents on Mars. But he gets caught up in the Venusian war of independence when his ship is captured by Venusian colonials. He is nearly blown up with the captured ship -- but they let him off at the space station because he was so stubborn about going to Mars.

This novel marks Heinlein's first benign depiction of extraterrestrials. A Venusian dragon by the name of Sir Isaac Newton befriends Jaime on board the ship from the space station to Venus. He turns out to be a genius physicist collaborating with Jaime's parents on advanced scientific principles that the colonials use to win the war with the government on Earth.