For April I'm going with a photo (not mine) of the Moon and Jupiter.
My favorite part of the photo is easy to overlook - if you look closely at Jupiter, you can see the four Galilean moons near it. There's some pretty significant scientific history to those four moons, I'd recommend Sidereus Nuncius (The Starry Messenger) by Galileo Galilei for the story.
Wow. At first I could see only two of the moons. Then I got real close to my screen and saw the other two. Neat pic.