First I have to say I love the book. I was up reading until 3am last night and I'm not really a football fan. You have done a great job of bringing in the "unbelievers."
That being said, on page 373 you said that, "Force equals mass times velocity." Mass times velocity is momentum. Force is mass times acceleration. Just a small observation.
I also liked the "Earth Ansible & Messenger", Ender would be proud.