Q. What would happen if the Earth and all terrestrial objects suddenly stopped spinning, but the atmosphere retained its velocity?

A. Nearly everyone would die. Then things would get interesting.

Q. Which US state is actually flown over the most?

A. Virginia, surprisingly thanks to flights like Toronto to Havana.

Q. Could the arrows of the Persians really have blocked out the Sun?

A. Yes, but not by aiming at the Spartans.

Randall Munroe is a former NASA engineer and the author of the highly acclaimed xkcd webcomic. More recently, he began a second blog called What If? in which he answers unusual and sometimes absurd questions like the ones above with interesting thought experiments.

As a science fiction author, I love this kind of stuff. Asking questions about the improbable or even the impossible can lead you down surprising avenues of research and provoke startling insights, and it’s just great fun. So when Randall wrote a book version of What If? I made sure to pick it up.

What If? the book contains a lot of old favorites from the website, including the very first one:

Q. What would happen if you tried to hit a baseball pitched at 90% the speed of light?

A. The city would be destroyed by a thermonuclear firestorm…and you would be entitled to advance to first base.

That’s basically it–more crazy questions like that, some are taken from the website, but the book also contains 51% new material, along with some of the weirder, sillier, and more disturbing questions that Randall declined to answer…more on that later. All in all, it’s definitely worth checking out.

My rating: 5 out of 5