The Planets by Dava Sobel

When we were in Washington, D.C. for the American Library Association Conference in 2007, we spent a good bit of our spare time along the Mall around the national museums. One of the displays that captured my attention was a set of signs along the street demonstrating the distances between the sun and its planets.While Mercury, Venus and Earth were within a few blocks of the initial sign, the other planets were farther and farther away. I do not think we actually made it out to Pluto, which was still being displayed by the Smithsonian as a planet, despite its recent expulsion from the club by the International Astronomical Union.

The Planets by Dava Sobel was written for someone just like me, a bit of a knowledge hound, always eager to learn new facts. Her discussion of the history of Pluto makes the downgrading seem quite reasonable. I had not remembered that Pluto was only discovered in 1930 and that with almost every refined study, its estimated size had gotten smaller. When I was a baby in the mid-1950s, Pluto was thought to be roughly the size of earth. Now that I am an adult, it is estimated that Pluto is less than 1 percent of the mass of earth. Things always seem smaller when you get older! It is now called a Trans-Neptunian Object.

Sobel tells us about all of the planets, starting with Mercury which is closest to the sun and often hidden in our daytime sky by the brightness of sunlight. Galileo tracked it as a spot across the surface of the sun to calculate its orbit. With a small orbit but slowly spinning on its axis, it has short years and exceeding long days.

I listened to Lorna Raver's unabridged reading of The Planets mostly while I was driving or cooking. I lost interest every now and then, but then something would pull me back. I think the history bits went much better than the mythology bits. I also enjoyed when Sobel brought in a little of her own story. Nerdy people like me will enjoy this audiobook.

Sobel, Dava. The Planets. Viking, 2005. ISBN 0670034460. Audiobook, 5 discs, 0739322869