Vermin of the sky and other worlds

Many books on astronomy are published every year. Most follow fairly conventional patterns, but these two books show special qualities, though in very different ways.

Our Worlds deals entirely with the members of the solar system. It consists of a series of eight more or less self-contained essays, each confined to one particular body and each written by an expert in that field.

For instance, the opening essay, "Exploring Mars", is written by Steve Squyers of Nasa, who has been closely concerned with recent probes to the planet; Ellen Stofen, one of the world's leading planetary geologists, deals with Venus, and presents the results of the latest research carried out by her and her colleagues.

"Moonlighting", by Carle Pieters, gives a graphic account of what a modern lunar astronomer is investigating; though men have been there (and will soon return) there is still a great deal about the moon that we do not know.

Asteroids and satellites? These were once dismissed as being unworthy of serious attention, but this is certainly not true today. Gone is the time when asteroids were even dismissed as "vermin of the skies".

Then there is Halley's comet, which returns every 76 years, and on the last occasion was greeted by a veritable armada of spacecraft. Titan, Saturn's senior attendant, has a dense atmosphere consisting largely of nitrogen. Io, which moves around Jupiter, has violently active volcanoes; Triton the one large satellite of remote Neptune, astounded astronomers when the Voyager 2 spacecraft showed that there were spouting geysers there. The solar system has provided plenty of surprises.

The most attractive feature of Our Worlds is that each author is obviously a genuine enthusiast. Moreover, there are personal touches not to be found in conventional books. Alan Stern has proved to be an expert editor, and the illustrations are excellent, particularly the colour section.

Our Worlds is a book not to be missed by anyone who has even a passing interest in our neighbour worlds. There is, however, one blemish; there is no index, and neither is there anything in the way of bibliography. No doubt these defects will be addressed in the next edition.

The Planet Venus is a very different book. It is written jointly by Mikhail Ya. Marov, of Moscow, and David H. Grimspoon of the University of Colorado and aimed at the serious student rather than the amateur. It is a massive volume, and much of the content is technical, though a large part is within the range of the reader with no more than modest background knowledge.

Only a few years ago, we knew almost nothing about Venus; we had no idea what lay beneath those obscuring clouds, and we were uncertain about whether the surface was dust-desert or aqueous. Now we know that Venus is a hostile world, but this does not make it any less fascinating.

Marov and Grimspoon present a comprehensive review of our present knowledge of the planet: its geology, its surface relief, its atmosphere, its origin and its evolution. Most of this information comes from the space probes, and here the Russians have played a major role. Results from the United States and what was the USSR have been skilfully combined, and the illustrations, including the half-tones, are fully adequate. The reference list is extensive, and so is the bibliography.

The information given here is completely up to date, and it is clear that the greatest care has been taken to ensure perfect accuracy. The result is a book that is an essential addition to any library dealing with solar-system astronomy.

No doubt it will need drastic revision in due course, but for the moment The Planet Venus must be regarded as a standard work and a great credit to both the authors and the publisher. In view of the importance of the book, the price cannot really be regarded as excessive.

Patrick Moore is the author of more than 60 books, mainly on astronomy.