Pluto: Sentinel of the Outer Solar System

The recent debate over Pluto's status as a planet has spurred a small flurry of books about the coldest, most distant, loneliest, and strangest official outpost of our solar system. Jones, emeritus professor of astronomy in London's Open University, delivers a detailed, matter-of-fact, and thoroughly accessible look at Pluto's origins, its history, and what it can tell us about our solar system—especially its outer reaches. Pluto's oblong shape and unusual orbit (highly elongated and tilted much farther out of the solar system than other planets) marked it as an outsider from the start. Now no longer considered a planet, it proudly stands as the first in the class of trans-Neptunian objects named for it: "plutino." The author writes in a clear, matter-of-fact style, including sidebars on related subjects from Kepler's laws of planetary motion to calculating a planet's surface temperature using nothing more complex than high school algebra. Jones's thorough approach offers popular science readers pretty much everything known about mysterious Pluto until the New Horizons spacecraft makes its rendezvous with Pluto in 2015. Photos and illus. (Oct.)