The Case for Pluto: How a Little Planet Made a Big Difference

Pity poor Pluto: It's a planet that was discovered because of a mistake, a planet that turned out not to be a planet at all, thanks to a still-disputed decision made in 2006. And yet, Pluto is the planet best-loved by Americans, especially children, one that may have contained the building blocks of life billions of years ago and may well serve as life's last redoubt billions of years from now.

In The Case for Pluto, award-winnin...