Secrets of the Moon – Understanding & analysing the lunar surface (Fielder)

Gilbert Fielder is a name synonymous with those who were fascinated by lunar geology during the 1960s to early 1980s, and also for anyone who studied planetary geology at University College London at the start of that era, or up until recently at Lancaster University. Many lunar astronomers probably have his earlier books Lunar Geology and Structure of the Moon’s Surface in their collection, and perhaps might wonder what the author would make of modern spacecraft data. This book gives you the opportunity to find out, but also is an interesting planetary geology book in its own right.

The carefully sequenced chapters take you through the early career of the author, and then on to puzzles about the Moon. Career paths are often lacking in scientific books, so this was welcome to see, especially given the experience gained by Fielder from interdisciplinary research, and from working with famous people such as Urey, Kuiper and Lovell. A read through this work should hopefully inspire any wannabe early-career scientists.

Pioneering work on modelling crater formation is covered extensively. Lots of specific lunar formations are discussed too, such as Aristarchus, Aristillus, Copernicus, Rupes Recta, Mare Imbrium, Tycho, and many more.

Perhaps a controversial topic, for some, is the book’s discussion about the Lunar Grid System which, although not discovered by Fielder, was extensively researched by him. This system has fallen out of favour since, as there are other explanations for the orientation of lineaments on the Moon, such as concentric rings from overlapping impact basins. However, this book shows that it may not be such a clear-cut case. Carefully laid arguments are presented, applied to old and new data. The book is good at making you stop and think whether currently accepted theories are correct.

Some readers may find the format a little unusual in that it has very short chapters, but this is made up for by there being 45 of them over 228 pages, plus an excellent glossary of terms at the end. In the view of the reviewer, the book has been somewhat priced out of the range of many amateur astronomers. However, by looking online one can sometimes find significant price reductions, especially for electronic versions – so these are worth keeping an eye open for.

Secrets of the Moon teaches us to occasionally question current thinking about lunar geology, especially when statistical analysis shows us something that differs from what prevailing theories suggest. It also warns us not to assume that all craters are impact in origin, as a few circular structures – heavily eroded ghost craters, or some very small formations – could have endogenic origins, and this could affect age estimates of the lunar surface that rely upon counting small craterlets of impact origin. So, with the crewed return to the Moon in the near-term future, this book is very timely and packed with interesting ideas.

Dr Anthony Cook is Director of the Lunar Section of the BAA and a research lecturer at the Department of Physics, Aberystwyth University.