My purpose here is to provide some pages to explain some astronomical matters that may not be understood by everyone. They are based on talks I have given to the Doncaster Astronomical Society or the Mexborough and Swindon Astronomical Society, short articles in the latter society's magazine, and some original pieces.
Large Numbers
I need to defend my attitude to the use of words denoting large numbers, particularly the words Billion and Trillion. These along with Million and higher numbers are evidently based on the numbers (admittedly a mixture of Latin and Greek), so Billion is Bi-illion and must mean two of M-illion, in other words million to the power of 2 or two millions multiplied together. There is no way it can mean three thousands multiplied together (or a thousand to the power of 3) as used in American English. In addition there is a perfectly good English word for a thousand million which is Milliard. For reasons I do not understand, that word does not seem to be well known in the UK, so I will generally use the cumbersome phrase thousand million.
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This paper describes how the cardinal points are defined in the sky. | 
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The Lunar Month (Can you spot the two major errors in my simulation of the Moon's motion here?) |
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The Origin of the Moon from the very beginning. | 
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Bode's Law is an empirical relationship between the distances of the major planets from the Sun. | |
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The way in which planets move in orbit around the Sun is described by three laws discovered by Johannes Kepler in the early 17th century. |