Call me a sucker, but I can’t seem to stay away from popular science books. When they’re good, they’re excellent (Outliers; the often-cited A Short History of Nearly Everything); when they’re bad, they can run the gamut from underwhelming (Physics of the Impossible) to “pretty damn bad” (Electric Universe).
I’m pleased to note, before getting to any discussion of substance, that Plait’s Death From the Skies! falls firmly in the former category.
When I was a young lad, I became enamored of a series of books called The Encyclopedia of Danger, which was a series of books devoted to things which could kill you. I began with Dangerous Insects, moved to Dangerous Mammals, and finally on to entries whose subject matter may seem more at home on TLC, such as Dangerous Professions. I tell you this not necessarily because I think you should read these books, but because it’s important that you understand some of the psychological currents at work in my delight at Death from the Skies. This kind of morbid fascination is, I would agree, universal in some degree, and the impetus behind everything from snuff films to horror movies to simple gossip.
Philip Plait, Ph.D.1 proposes to scare you (First line in the book: “The universe is trying to kill you.“), but almost always pull you back from the precipice at the last moment, usually by pointing out the literally astronomical odds of these sorts of cataclysms occurring. The flow of chapters goes from the most likely (being hit by asteroids or meteorites) to the least likely (being fried by a gamma ray pulse) or least relevant (heat death of the universe).
Each chapter begins with an italicized section narrating the horror in potentia: movie trailer-like, the scene begins with little girls playing hopscotch and kittens being precocious, and suddenly an asteroid six miles long slams into the continental United States, instantiating a tremendous shockwave that circumnavigates the globe (twice!), blasting away humanity in a sudden rage of heat and pressure. Whoever or whatever left alive after the initial tempest will surely die as the thrown debris blots out the sun and devastates the food chain from the bottom up.
Giving more credit to Michael Bay than is probably due, Plait serious considers the idea of landing a rocket on such an asteroid, provided we have advance warning of it. In fact, he runs through a number of scenarios, all of whose efficacy varies depending upon the state of our technology, the orbit of the damnable rock, and the amount of time we know in advance. Ten years is best, he says, though often we don’t see such things until they pass us by (!). But these impacts, though still rare on any scale to arouse alarm2, are more or less guaranteed to happen (evidence shows that they already have in appreciably recent history, the most recent being the Tunguska Event in 1908). But they are also the sort of event we have the most power to predict and counteract (and also they give us the most chance of survival).
By the time Plait is talking about supernova, the likelihood of the doomsday scenarios he describes are infinitesimally small: in any given lifetime, you’ve got a 1 in 10,000,000 chance of dying from a supernova; even that seems relatively low. The odds of us being swallowed up by a black hole that wanders too close (or our solar system dropping too close to the relatively tiny black hole at the center of the Milky Way) are approximately 1 in 1,000,000,000,000. These phenomena as real dangers are an academic exercise; we can make vague predictions about the damage to the Earth based on estimated energy output or gravitational effect, but Death From the Skies is not a real-life encyclopedia of danger. In that case, it didn’t appeal to any sense of pornographic morbidity that I may harbor.
No, what made this book so compelling is that there is nothing more humbling than reading about astronomy. The sheer scale here is more than any of us can really appreciate. A red giant star, for instance, when going supernova, can easily—in an instant—release an amount of energy equivalent to our humble sun’s entire lifetime out of energy; or, to put it another way, the output of one hundred billion billion (that’s two “billions”) of our sun at a given moment in time. That’s massive; it’s really beyond our ability to appreciate. I sunburn after ten minutes in July, for goodness’ sake.
Much of the book is filled with this: Plait takes astronomical phenomenon as a narration, stepping us through the stages of cataclysm that lead to an exploding star or a gamma ray burst or the collapse of a star into a supermassive black hole. Most humbling yet is his final chapter, which, though hardly related to prescient warnings of asteroids or solar flares, is the eventual heat death of the universe, which is an extrapolated event based on somebody’s mathematical equations, wherein all matter is ultimately dissipated and there is zero activity in the entire universe. If that makes you a little queasy, don’t worry: it’s not supposed to happen for 1092 years3. Speculative, sure, but it’s the sort of writing that makes you want to go pour yourself a drink.
Death From the Skies is, in my view, the very definition of popular science writing. It isn’t afraid to pull our scary numbers or reference quantum mechanics, but all along it manages to be abstracted enough to appeal to those of us without doctorates in astronomy. Despite its somewhat lurid title, it is solid science writing, and manages to be wholly engaging the entire time. Plait has created a real gem here; I would recommend it to any and all comers.
- Doctorate in Astrology, 1994, University of Virginia; his thesis was (what else?) about a supernova[↩]
- The earth is hit with millions of tons of debris, but it all breaks apart into dust in our atmosphere[↩]
- That’s 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 years; I guarantee that is a longer span of time than you could ever imagine, even with the greatest of pharmacopeia[↩]