So, you already know that my wife, Lizzie K. Foley, wrote a book called Remarkable, which was published in 2012 and is, quite probably, the greatest middle-grade novel ever written. If you are a kid aged 8 and up, or if you know a kid aged 8 and up, you should buy it.
This is not what the cover looks like, but this is what the cover would look like if it had been published in the pulp era of science fiction magazines.
This was created using the PULP-O-MIZER, which I encourage you to waste the next several hours playing with.
For completeness, and to facilitate your resharing needs, here's that cover rendered in square, "facebook-friendly" format (which avoids the weird cropping thing that happens when you post tall images there).