More scope for star-hoppers

There was a time not so long ago when even the leading amateur was equipped with nothing more than a moderate-sized telescope, a set of star maps and a camera. Things today are very different. Electronic instruments have come to the fore and computers have, to a large extent, taken over. Consequently, the results obtained by skilled amateurs can match those produced by professional observatories in the recent past.

Michael Covington is not a professional astronomer, and his main degree is in linguistics, but he is a leading amateur and author of a widely read book on astronomical photography. His two new books are complementary, and will be of great value to amateurs who are getting to grips with modern-type equipment. Each book is self-contained but their value is enhanced if they are taken together.

How to use a Computerized Telescope describes telescopes of all types, and introduces computerised equipment. The author has one very significant comment to make at the outset. It has been suggested that computers make observing too easy and "take all the fun out of it", but this is not true.

A properly set-up computerised telescope will find objects at once, without the need for tedious searching, but this does not rob astronomy of its challenge or entertainment: "Suddenly, I was spending my time looking at objects instead of for them. No longer preoccupied with 'star-hopping', I could spare the time and attention to study the celestial objects themselves."

It is true that if a computerised telescope is to be used, the beginner must have at least a rudimentary knowledge of the way in which a computer works, but by now most people do have this, and Covington goes "back to basics" as far as possible. He writes clearly and the text is presented in an orderly manner, so that the reader is unlikely to become confused.

Following the author's instructions, setting up the computerised telescope is not nearly so daunting as might be expected. There are, however, pitfalls, and a useful section of the text deals with how to solve some of the problems that are almost certain to be encountered at one time or another. Moreover, the newcomer will be relieved to find that once the telescope is properly set up, operating it is not difficult.

The first part of the book is headed "Telescopes in general" and deals with all aspects, from the choice of equipment to observing sites, types of mountings, image orientation and much else. Astrophotography is not neglected; old-fashioned plates are rapidly giving way to electronic means such as charge-coupled devices.

The most important part of the book deals with the setting up of computerised instruments, and the author has wisely tackled this by detailed discussions of "three classic telescopes": the Meade LX200, the Celestron NexStar 5 and 8, and the Meade Autostar ETC and LX90. Even with no more than a very basic knowledge of computers, the instructions given here will enable the newcomer to use a modern-type telescope to real advantage.

The companion book, Celestial Objects for Modern Telescopes , will appeal equally to amateurs using what may be termed "old-fashioned" equipment.

There are sections on night vision, limiting magnitudes, seeing conditions and much else. Observations of the Moon and planets are discussed in detail, and there is a long section about the Sun (there might be a case here for extra stress on the dangers of solar work, for example by the use of inadequate filters, but this is largely a matter of common sense). There is a good introduction to general astrophysics, with notes on modern star catalogues, variable stars, binaries, star clusters and novas.

Rules for pronouncing astronomical names are given, though different authorities have different ideas about these, and the average telescope owner will not care greatly about correct pronunciation.

There is a list of 200 objects suitable for observation, all within the range of an 8in (20cm) telescope under average conditions; the list has been very carefully compiled and each object is described. This is where the computerised telescope comes into its own, because some of the objects are elusive, and searching for them by the old star-hopping method would be time-consuming even for the experienced observer. It is clear that the author has carried out a tremendous amount of personal observation and anyone working through the list will end up with a good knowledge of the night sky.

The illustrations in both books are satisfactory and the writing is pleasingly clear and fluid. There is only one real problem, and this is certainly not the author's fault; most of the references are American and, in some cases, unavailable in Europe. In the next editions, there is a case for adding European equivalents wherever possible.

Author and publisher are to be congratulated; Michael Covington's guidance is both timely and skilful. No amateur astronomer should be without these two excellent books.

Sir Patrick Moore has presented the BBC's The Sky at Night for more than 45 years.