This is the diary of a self-centered 16 year old (redundant, I know) whose world changes. That's literal, not a figurative overstatement: something crashes into the moon, which changes the moon's orbit and wreaks havoc on the planet around which it orbits.
Did you know that I keep emergency food and water in the basement, that I chat casually with the Red Cross volunteers at community festivals? Not only do I have a hand-crank-powered-flashlight-and-radio, but I know where it is right now. Just writing that down makes me want to make sure it is where I think it is....just in case. This book made those "just-in-case" parts of me, the Worst Case Scenario thinker, go absolutely crazy. I had to refrain from writing down exactly what I thought their supplies would be, and how long I thought the supplies would really last. I couldn't stop myself from "idly" perusing several astronomy and physics boards to see the truth of the science behind the plot. (At some other time and place, I could summarize what I found, if you--dear reader--so wanted.) In other words, this book hit the panic button lying only slightly hidden from view.
The book is probably better enjoyed if you aren't obsessing about the possible realities. Miranda is an interesting enough character. She is selfish a little longer than is comfortable, but she does ultimately have an interesting story to tell. She remains a relatively believable teenager, which I think keeps the reader along with her.
I'm not sure that I'll read the sequel. This makes for a pretty good stand alone book, for one thing. For another, I'm not sure that my basement can handle another doubling of my emergency supplies.