Register Log in

Scientific Method / Science & Exploration

Lives of the Planets: the good, the bad, and the gas giants

A compelling topic and approach is marred by odd gaffes.

Planetary science is a fast-moving field, especially in this era of Mars rovers, orbiting mappers, and long-lived exploratory probes. Even ground-based telescopes have made astounding discoveries, thanks to relatively new optical techniques. Our Solar System—and exoplanetary systems—have been opened to remote exploration, and intriguing discoveries are happening at an astonishing rate.

Knowing all this, I was excited to pick up the new paperback edition of Lives of the Planets, Richard Corfield's 2007 book on planetary science and the exploration of the Solar System. As I expected, a lot of the latest and greatest findings simply could not be included, making the book seem a trifle outdated. While a few new bits of data (including the loss of the Spirit rover) did make it into the paperback, these updates were spotty at best. I don't wish to criticize the book on these grounds, however, since a lot of new science has emerged since 2007.

That doesn't mean there aren't grounds to criticize it, though. Lives of the Planets has far more serious problems that make me hesitant to recommend the book.

Each chapter of the book focuses on a different part of the Solar System, starting from the center and working outward. In beginning with the Sun and ending with a few short words about exoplanets, Corfield's book truly is a grand tour. It covers a bit of stellar evolution, planetary formation theory, and the history of astronomy. The individual chapters include not only our scientific knowledge, but also the history of humanity's observation and exploration of the particular object.

Corfield's book has many good aspects: he has an obviously great love for planetary science and space exploration, which comes through strongly in the text. He also focused largely on how we know what we do about the Solar System: how the various space probes operate and how the data are turned into knowledge. These are the sorts of facts that end up context-free in many other popular science books. Much of the book is devoted to describing the design of probes, along with the political machinations that are often required to get the off our planet.

As a lifelong fan of the Voyager probes, I was especially fond of Corfield's coverage of those missions, which set the standard for exploration of the outer Solar System. (Voyager 1 traveled to Jupiter and Saturn, while Voyager 2 went to both those planets and continued on to Uranus and Neptune, the only probe ever to do so—and none are projected to retrace its steps.) He also provided a lot of detail about the Soviet Venera probes to Venus, some of which was new to me.

However, Corfield's attention to mission details sometimes seemed a bit misplaced. He spent more pages on the failed Beagle 2 probe than on many successful missions; while I understand his personal engagement in that project, I don't see how it supports his overarching points to linger over it as much as he does.

He also classifies the Viking Mars landers, which were extremely well-designed experiments, as failures—solely on the basis that their search for life gave null results. Failure obviously comes in many varieties: rockets exploding on the launchpad, instruments failing to deploy as planned, and so forth, but conflating Beagle 2's silence, which amounted to a terrible freak accident, to Viking not finding life seems to be a misunderstanding of how science operates.

Another odd misunderstanding of scientific practice is when Corfield discussed what constitutes a planet. At times (especially the concluding paragraph of Chapter 6), he almost seemed to espouse an absolute view of "planet," stating "we now know on the basis of other evidence that Pluto is not a planet." But oddly, he continues with, "What, then, of Neptune? Is that far guardian perhaps also a Kuiper Belt object?"

I have never read a planetary scientist assert that Neptune is a Kuiper Belt object—those are tiny bodies composed of ice and rock, while Neptune is a large gaseous planet composed of highly compressed water, methane, and other hydrogen compounds. Beyond that odd sentence, his logic seems strange to suggest Neptune may not be a planet on the grounds that Pluto is not. A "planet" is not an archetype, handed to us by the gods; it's a useful category with a definition that has evolved over the centuries, and may yet change again.

Things generally got worse when Corfield focused on the science instead of the exploration. The book has a number of errors, some of which are bizarre. The weirdest is his assertion in Chapter 3 that "whales evolved from land-dwelling animals related to turtles." I suspect this was an slip of the brain rather than a true conceptual error, since it's so obviously wrong, but why didn't an editor catch it?

As a more typical example, the author royally screws up stellar evolution, stating in Chapter 1 that stars move along the Main Sequence during their lifetime; in actuality, a given star sticks close to one spot on the Main Sequence (the period in which a star fuses hydrogen into helium in its core), which is predetermined by the star's mass. Only late in their history do they start to diverge from their location.

Beyond errors of this type, Corfield spent a lot of time on the Titius-Bode law, a formula devised in the late 18th century that proposed a mathematical relationship for the location of the planets. The Titius-Bode law had two noteworthy successes: it predicted the location of Uranus, discovered in 1781, and the discovery of the asteroid Ceres in 1801. But Neptune, Pluto, and other distant objects don't fit the model, and few astronomers think the equation has any connection to an underlying physical law for that reason. I'm uncertain why Corfield thought it is still relevant enough to justify 10 pages of material when planetary science has moved far beyond it.

Finally, Corfield comes very close to assigning equal blame for global climate change to sunspot activity: "At the present time, the data suggest that sunspot activity warms the Earth's surface to about the same extent as greenhouse gas emissions and on about the same timescale." (Emphasis in the original text.) While the role of solar activity on Earth's weather has mysterious aspects, most climate scientists are very clear: recent climate change is due mostly to human activity.

All in all, errors and confusions weaken Lives of the Planets so much that the book is untrustworthy. I found myself marking many pages simply because I'm bothered by the assertions printed on them. With so many problems I identified, I also wonder if I might have missed others—not a good feeling to have when reading a book intended to be authoritative in some sense. Ultimately, I think a good metaphor for the failure of Lives of the Planets is a noteworthy omission: there are no references, footnotes, or bibliography. I think Corfield could have used a little more fact-checking.

Expand full story

You must to comment.

You May Also Like

    Need to register for a new account?

    If you don't have an account yet it's free and easy.