I was on page 25 when I first thought, "Oh, I wish I didn't know that."
I'd heard that a large asteroid is going to come very near Earth in 2029 but that it isn't going to hit us. Astronomer Philip Plait verifies that. But.
And this is a very big "but." It seems 99942 Apophis is going to come so close (closer than some weather satellites) that Earth's gravity might alter its orbit. And if it alters it in such a way that it passes through a small region of space called a keyhole, the orbit will change enough that on its next pass, in 2036, it will hit us. We might not go the way of the dinosaurs. But then again, we might.
Most of Plait's book is dedicated to telling us just how bad it could be and how the solutions we've seen in the movies probably wouldn't work. But then again, they might.
Plait's book is the latest in the genre of science made easy — and amusing — for regular folk. He's not as elegant a writer as Bill Bryson in a similar book, A Short History of Nearly Everything, and his jokes aren't as funny. But he's good with analogies, and he's smart to focus on the dramatic and the scary.
The first chapter, about impactors — asteroids, comets — is the best. Others tell us about the immense size and danger of the sun, what would happen if a supernova were to occur in our solar neighborhood (bad news), gamma rays (really bad news), black holes (the worst news: spaghettification!), the odds of being annihilated by aliens, and so on.
I was fascinated to learn that when the sun dies, it will expand so much that it will engulf our planet. That will be a pretty rotten time to be human. Unless, of course, we can manage to move our planet back a safe distance. Using the slingshot effect, astronomers say, this could theoretically be done. Of course, we could end up being ejected from the solar system, too. But.
We have a few billion years to figure it out.
Kate Brassfield can be reached at firstname.lastname@example.org or (727) 893-8216.