“The most beautiful sight one can see in a telescope” is the way Isaac Asimov describes the planet Saturn. What astronomers saw through the primitive telescopes of the 1600s was so startling that they did not dare announce it: Galileo and Huygens saw the mysterious rings, but the news of their discovery was hidden in secret code.
In Saturn and Beyond, Isaac Asimov relates this fascinating episode and the steady stream of amazing discoveries about the region beyond Saturn, which was once thought to be the limit of the visible solar system. As told by this supurb science writer, the story of Saturn and the outer planets—Uranus, Neptune, and Pluto—and new findings such as Pluto’s moon demonstrate how exciting astronomy can be.
With complete information about Saturn and the farther reaches of our solar system, this book is the perfect preparation for the new revelations from our Saturn probes.
This book is a member of the series which started with Jupiter, the Largest Planet and has all the strengths and weaknesses of the earlier volume. It’s a little less thorough in its examination of its subjects, of course, because there are four of them, not one, but it still has a complete examination of various physical properties of planets and lots and lots of interesting statistics to see how Saturn, Uranus, Neptune, and Pluto stack up.
It does, however, suffer rather badly from the passage of time, just as does Jupiter, the Largest Planet. The Voyager probes have passed Saturn, Uranus, and Neptune, and Cassini has been doing a bang-up job around Saturn. Huygens and Cassini have taught us enough about Titan to warrant an extra chapter. Although Pluto has yet to be visited by a human spacecraft, the years spent near perihelion made it possible for our knowledge of the erstwhile ninth planet to expand tremendously. (At least the existence of Uranus’ rings and Charon was known at the time the book was published. Neptune’s rings were still unknown.)
The real omission, in modern terms, is of the numerous smaller bodies beyond Pluto, including the three other dwarf planets: Eris, Haumea, and Makemake. The decision to create the “dwarf planet” categorization and demote Pluto deserves a chapter in and of itself, as well as the Kuiper belt and plutinos in general. Of course, Asimov would have had to have been pretty prescient to have anticipated all that in 1979—but he does include the sentence, “It is hard to think of Pluto as a planet now. Perhaps it is one more of the Chiron-like bodies that may fill the outer solar system.”
Not bad, actually.
(An aside: I don’t feel bad for Pluto on account of its “demotion,” because there is precedent. The first asteroids to be discovered were counted as planets through the first half of the nineteenth century, until astronomers realized that there really were an awful lot of them. One of the definitions of “planet“ suggested in 2006 would have promoted Ceres back to planetary rank, in fact. It’s poor Ceres I feel sorry for.)
I would, therefore, once again give it an unqualified and enthusiastic recommendation to the general Asimov fan and a more guarded recommendation to someone who wanted to use it as a source for information about the outer planets. While the information it contains is still accurate, there’s enough that it leaves out that one has to be a bit cautious in using it.