This book gives a clear, up to date description of our star and our solar system, which is why I think any amateur astronomer should include this book in their own collection. 

This is a must-read for anyone who is interested in how the sun works from nuclear fusion to protection of the solar system. 

Dr Lucie Green also teaches you the history of how we gained our knowledge and explains the basics before jumping into too deep information.

While I’m a keen pursuant of the underpinning science of our hobby, I’m certainly no ‘mathematician’. Ian Stewart on the other hand, IS an accomplished mathematician, science writer, presenter and recipient of the Michael Faraday Prize and Christopher Zeeman Medal. So it was with some trepidation that I picked up ‘Calculating the Cosmos: How Mathematics Unveils the Universe’.

A quick flick through the 300 or so pages reveals almost no ‘equations’ as such. So for those looking for a comprehensive textbook of the mathematical equations which steer the Universe through its life - this isn’t it. Instead, the author includes many diagrams and graphs which illustrate the principles being discussed and these are well described in the text. The aim of the book is to impart a general understanding of how the behaviour of the observed universe is defined and embodied in the underlying physics and mathematical principles without burdening the reader with what would undoubtedly be some formidable math.

However, while the author spares us the detail of the mathematics, he does not limit the scope of the book in terms of its coverage of the evolution of the universe. The book starts with a quick review of the history of our understanding of gravity - Kepler, Newton, Einstein et al. - uses these to illustrate how the principles are embodied in star and solar system formation. He piles in the detail of how we have arrived at the current distribution of planets in our solar system and then goes up a gear to look at the dynamic behaviour of the asteroids and how Lagrangian mechanics results in the behaviour of the Greek and Trojan asteroids. He uses this as a springboard to go on to discuss how orbital mechanics governs everything in our solar system from the motion of the planets, their moons and how we employ these to more efficiently boost the trajectories of man-made objects to the outer planets. 

The book progresses with a brief discussion of stellar formation, the behaviour of the Cepheid variables and their importance as ‘standard candles’ in contributing to interstellar distance measurement. The author has a brief dalliance with our own galaxy, galaxy formation in general and also of the hunt for exoplanets, examining the mathematical tools employed in these areas.

From here on things become very much more ‘cosmological’ as the author looks at black holes and their theoretical properties. He also embarks on discussion of the various theories of the formation of the universe - creation from nothing, its early life and subsequent expansion to our vision of it today. Inevitably he goes on to discuss the ‘missing mass’ conundrum, dark matter and dark energy.

But there is a notable divide in this book. To anyone who has studied at least some basic astronomy theory, the subject matter of the first two thirds feels comfortably solid and believable. But it’s in this last third of the book that things start to feel unnervingly ‘fluid’. The author describes multiple theories for how things like the structure of the universe might be explained by a variety of emerging theories in particle physics and quantum mechanics. Similarly you know you are in trouble when the book concludes with a discussion of ‘multiverses’, of which Ian Stewart points out that ‘mathematical physicist, Brian Greene describes nine different types of multiverse’ of which the author goes on to discuss just four.

And it’s at that point, I for one, invoke the old adage that while there are several theories for how something works, you cant draw any conclusions as to which one (if any) is right. 

Notwithstanding this inevitably squishy ending, the book was an enjoyable read.

John Neal

The Yearbook of Astronomy was started in 1962 by John Guy Porter, who presented the “Night Sky” on radio which predated “The Sky at Night” on TV (his programme was the last thing my mother heard before going into hospital to give birth to me). He was assisted by Patrick Moore who soon took over as editor. The Yearbook survived the death of Patrick Moore in December 2012, but was suddenly dropped by Macmillan in 2017. Brian Jones and Richard Pearson produced an “emergency” edition in 2017 funded by a small group of subscribers.

Given a new berth by the publishers Pen and Sword, the Yearbook is now back to its usual size. It consists of three sections: monthly notes, an article section and a back section which covers variable stars, double stars, deep-sky objects and astronomical organisations. The monthly section has all the details one would expect in such a section (planets and such like), but each month also has an article attached. This is a departure from the older version and while the articles are often interesting I find them a distraction – they should be in the article section and the monthly notes should be longer. I also find it disappointing that the list of double stars has been reduced from five pages to just over a page. Given the increasing interest in imaging by amateur astronomers, it is a pity that there is little for imagers in the volume.

However the Yearbook remains a useful tool for visual observers and also provides interesting reading for cloudy nights.