Preface and AcknowledgementsPosted: March 16, 2013
Astronomy, the study of the heavens, and your Spectrum are just made for each other! The excellent graphic potential of the Spectrum means that dusty subjects like Kepler’s or Bode’s Laws can be brought to life.
This book emphasises the visual side of computing and astronomy: in doing so it may displease some purists who only wish to see astrocomputing as number crunching to the nth decimal place. However computers are in the business of communication. Just as BASIC is an acceptable computer language, so a graphic display, in addition to pure numbers, is an important aid to the rapid assimilation of facts and concepts.
This book is not specifically directed at astronomers but at Spectrum owners who wish to expand their computing interests into other fields. I’ve kept explanations of the mathematics or trigonometry used in some of the programs to an absolute minimum. You don’t need to know about such subjects to RUN the programs — simply key in and RUN. I’ve also explained the general working of each program, in full, where appropriate and included relevant information about astronomy.
There is a commonly held impression that everything which happens in science is happening today. In many ways this is a good thing as it means that so many people are interested in what goes on. But astronomy has a long history and standards, formulae and computing devised centuries ago, even before the telescope was invented, are still in common usage. (A classic example would be Hipparchus’ stellar magnitude scale — still in use after 2110 years.) Not only is astronomy an ancient science, computing is older than you might think!
We are all prisoners on this beautiful island Earth — a tiny speck sailing through the cosmos. It is hoped that some of the programs included in this book will entice the user to flights of fancy to other worlds and so widen an experience of the mind.
Grateful thanks are due to Dr Peter Duffett-Smith for his published algorithms used in the two planetary ephemeris programs and to James Weightman who wrote the bulk of the Jovian satellites program for this book, based on an algorithm by Jean Meeus.