Rocket Ship Galileo

When Rocket Ship Galileo was written in 1947, rocketry was in its infancy. The moon landing was still a few decades away. World War II had only recently ended and was fresh on everybody's mind.

The book is a simple adventure. A bunch of kids team up with a scientist relative and build a rocket to go to the moon. The physics and technology are covered in detail. Once they get there, they are surprised to run into other people. It turns out the others are Nazis with a plan to take over the earth with missles from the moon. The boys defeat the Nazis, saving the earth and return successfully to earth. Who needs superheroes when regular boys can save the world like this?