The Pluto Files: The Rise and Fall of America’s Favorite Planet; The Hunt for Planet X: New Worlds and the Fate of Pluto

The Pluto Files: The Rise and Fall of America’s Favorite Planet , Neil deGrasse Tyson , W. W. Norton, New York, 2009. $23.95 (194 pp.). ISBN 978-0-393-06520-6

The Hunt for Planet X: New Worlds and the Fate of Pluto , Govert Schilling , Copernicus/Springer, New York, 2009. $27.50 (303 pp.). ISBN 978-0-387-77804-4

It has been three years since the International Astronomical Union voted to remove Pluto from the pantheon of planets. But even now, if you’re an astronomer, and you admit it to a neighboring airplane passenger, one of the first questions you’re likely to be asked is, “What did you guys have against Pluto, anyway?” The question is always a great opportunity to put Pluto into its true context in the solar system, to explain about all of the new discoveries in the Kuiper belt out past Neptune, and to talk about how science—and scientific categorization—works. By the end of the flight, your neighbor is nodding along and has even learned a little astronomy. One flight at a time, the world is slowly coming to terms with Pluto’s demotion and our new view of the solar system.

Now, if you’d rather watch your inflight movie than talk about the Kuiper belt, you’re finally in luck. The passage of time has allowed the emergence of a slew of new books on Pluto and planets. The first two to appear are all you will need in your carryon: The Pluto Files: The Rise and Fall of America’s Favorite Planet by Neil deGrasse Tyson and The Hunt for Planet X: New Worlds and the Fate of Pluto by Govert Schilling cover much of the same ground, but they are likely to appeal to very different readers. If you don’t know which one to lend first, choose Tyson’s book. He tells a good-humored but serious tale of his personal role in raising the world’s consciousness about Pluto’s true standing. Astronomers had been privately questioning the status of Pluto since the 1992 discovery of the first small object in the Kuiper belt. But it was the Hayden Planetarium’s decision to group Pluto separately from those other eight big things in the solar system that eventually brought the astronomers’ private dilemma into the open.

In his book, Tyson, the planetarium’s director, plays the role of the messenger who gets shot at, but you can tell that he relishes both delivering the message and dodging the bullets. And he delivers the message about Pluto well. Although he gives a bit of the history of planetary discovery and explains where Pluto fits in, Tyson mostly provides a spirited telling of the battering he’s endured from the public and the astronomical community over Pluto’s fate. His tales of schoolchildren’s outrage are amusing enough, but for my money, it’s his discussion of the handful of astronomers still sentimentally attached to Pluto’s planethood that comes off the funniest.

Now if, after finishing the quick and breezy Pluto Files, your airplane neighbor still has questions or wants to delve deeper into the science and the scientists, then you are still in luck. Simply pull out The Hunt for Planet X and your neighbor is likely to be absorbed throughout even the longest flight. The book goes into enough detail and interesting diversions that you might find your fellow passenger reluctant to hand the book back to you when the airplane sets down—so buy a few as giveaways.

Schilling gives a journalistic account of time periods covered in Tyson’s book. But it is a type of account that will never be repeated. Schilling had the good fortune to be already at work on a book about searching for planets in the outer solar system when they suddenly became big news. His book not only gives the history of the exploration of the outer solar system, but also includes vignettes of visits to almost all of the astronomers currently active in the field. Most of those visits occurred while the discoveries and controversies were still fresh and unsettled. Though there will likely be subsequent retellings of this bit of history, Schilling’s account will be the only one from a journalist embedded amongst astronomers—I was one of them—as it happened. It was interesting to read what my colleagues and I said to him before we knew the final outcome of the searches in the outer solar system and how the arguments about planethood would eventually play out.

My favorite part of Schilling’s book, I must admit, is the chapter he devotes to Nibiru, a rogue planet that will supposedly collide with Earth in 2012. Haven’t heard of that one? That’s okay: It exists only in the minds of pseudo-scientists and conspiracy theorists. I get questions about Nibiru all the time, but I’ve never read a coherent explanation of what it is supposed to be, where the myth originated, and why people still talk about it. Schilling’s many reasons why Nibiru makes no sense will never change the minds of those devoted pseudoscientists because now, of course, Schilling has simply become part of the cover-up. But, finally, I have a book to hand people when they ask me whether I think the world is going to end in 2012. “Read this chapter and tell me what you think,” I’ll say. And then I’ll put on my headphones and go back to thinking about how to find the real Planet X.