I had a vested interest in Meeus's latest book. In 1999 I bought his 'Mathematical Astronomy Morsels' and was immediately delighted by a mouth-watering selection of mathematical astronomy tidbits. It immediately begged me to ask some pertinent questions and will, no doubt, prompt a similar response from any intelligent observer.

I am certainly no mathematician but I am interested in the way the solar system works, and to appreciate it fully there is an advantage in having mathematical explanations. Previous books by Meeus have been aimed at the mathematically minded astronomer who wants to understand the solar system from this point of view as a basis of working with the dynamics. But Morsels and now his new book, More Morsels, are subtly different and a much lighter read for the astronomer who isn't necessarily interested in the maths for its own end but who appreciates a fuller explanation of predictable astronomical events and observations without having to take onboard the deep understanding of the mechanics. As they say, ask a silly question….

In January 1982 I saw a totally eclipsed moon occult the 10th magnitude Eskimo Nebula. So having read his first Morsels, I e-mailed Meeus with the question, how often can the totally eclipsed moon be see to occult a deep sky object? The initial response was not very encouraging, in fact rather dismissive, but then a flurry of e-mails from Meeus over the next few days resulted as the implications of the question obviously sank in. Occultations of faint deep sky objects can only be seen when the moon is totally eclipsed. The answer (I was sworn to secrecy for over two years) was the subject of six pages in section 27 in More Morsels. The answer is, not very often!

This is the sort of mathematical curiosity Jean Meeus elucidates so brilliantly. Such questions have absolutely no scientific use but for the observer who may need to know when the brightest Full Moon is visible, or the times when Jupiter can be seen without it's retinue of Galilean satellites or, for a given place, what day of the year has the shortest twilight, then this latest book and his previous one, is a mine of useless information impossible to find elsewhere. I unreservedly recommend both books.

Kevin Kilburn, F.R.A.S.