Nearly five years ago, on August 25, 2006, as a result of a vote at the meeting of the International Astronomical Union, Pluto lost its status as a planet.
Sure, people had recognized the oddity of Pluto since its discovery by Clyde Tombaugh, but while "it looked and behaved like no other planet known, there was not other way to classify it, so it became accepted as the ninth planet." So how did we get to the point at which Pluto's planetary status was questioned?
In 1999, Mike Brown was a young astronomer with a hunch that, despite accepted astronomical wisdom, there was another planet beyond Pluto. He and fellow astronomer made a friendly bet about whether or not a new planet would be found by the end of 2004, with the loser paying up in the form of five bottles of champagne. The only potential snag Brown thought of at the time was, how exactly do you define what a planet is?
Beginning with this bet, How I Killed Pluto and Why It Had It Coming details how Brown went on to discover several new, um, planets. At least, they were considered planets when their discovery was first announced, despite Brown's belief that they, and Pluto, were not actually planets. It didn't matter that one of them was slightly bigger than Pluto; he was adamant that it wasn't a planet and neither was Pluto. Despite Brown's strong feelings on the matter, the choice of terminology wasn't up to him. Instead, it was up to the members of the International Astronomical Union to define what planet means, and whether or not Pluto, and thus also Brown's discoveries, were in fact planets.
Part astronomical history, part astronomy lesson, part memoir of Brown's family life during the decade, How I Killed Pluto and Why It Had It Coming is a surprisingly entertaining and humorous read.* (Although the book does not include a bibliography or further reading section, much to my dismay.) Brown writes in an accessible, conversational style that makes his passion for astronomy obvious. His expertise in his field is clear, but he shares his knowledge simply and lucidly for a lay audience. The book was published for an adult audience and some teens will not be as interested in the details of Brown's family life, but may find inspiration in how his childhood interest in planets led to a career as an (depending on your point of view, planet-killing or planet-redefining) astronomer. I found a couple of moments in the chronology a bit confusing, but overall, How I Killed Pluto... is a stimulating look at our solar system and how Brown deliberately undertook his search for new planets.
Book source: public library.
* It also garnered my favorite author blurb of the year thus far, courtesy of Neil deGrasse Tyson on the back cover, which begins: "Finally I have someone to whom I can forward the hate mail I get from schoolchildren. After all these years, the real destroyer of Pluto has confessed."
Cross-posted at The YA YA YAs.