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Stellar Evolution Microcosm of Astrophysics Nature Vol. 278 26 April 1979 Spring books supplement 817 soon realised that they are neutron contrast of the type. In the first half stars. It now seems certain that neutron Stellar of the book there are only a small stars rather than white dwarfs are a number of detailed alterations but later normal end-product of a supernova there are much more substantial explosion. In addition it has been evolution changes, particularly dn chapters 6, 7 realised that sufficiently massive stellar and 8. The book is essentially un­ remnants will be neither white dwarfs R. J. Tayler changed in length, the addition of new nor neutron stars but will be black material being balanced by the removal holes. Rather surprisingly in view of Stellar Evolution. Second edition. By of speculative or unimportant material. the great current interest in close A. J. Meadows. Pp. 171. (Pergamon: Substantial changes in the new binary stars and mass exchange be­ Oxford, 1978.) Hardback £7.50; paper­ edition include the following. A section tween their components, the section back £2.50. has been added on the solar neutrino on this topic has been slightly reduced experiment, the results of which are at in length, although there is a brief THE subject of stellar structure and present the major question mark mention of the possible detection of a evolution is believed to be the branch against the standard view of stellar black hole in Cygnus X-1. of astrophysics which is best under­ structure. There is a completely revised The revised edition of this book stood. Because most parts of physics­ discussion of the evolution of low mass remains a very good non-mathematical such as nuclear physics, atomic physics, stars following the helium flash, the introduction to stellar evolution and the thermodynamics and statistical physics, explosive onset of the conversion of paperback edition is very reasonably electromagnetism and gravitation-are helium into carbon. The major change priced. 0 involved in determining the structure concerns stellar old age and death. of a star, it is a very suitable topic in Shortly after the first edition appeared, R. I. Tayler is Prof,r.vsor of Astronomy at was applied physics to introduce to under­ pulsars were discovered and it the University of Sussex, Brighton, UK. graduates. It is also possible to present the subject to an audi,ence with a often do not succeed in presenting the slighter knowledge of physics and this of more serious aspects of the subject, and is the concern of Professor Meadows. Microcosm their readers might not realise the im­ When the first edition of this book portant part which is played by astron­ was published in 1967, it received a astrophysics omy in postgraduate physics education. warm welcome because of the manner Mitton is a physicist, and emphasises in which it bridged the gap between F. Graham Smith the basic physics throughout, but his very superficial discussions of stellar book is nevertheless a popular book. and evolution in books for He eschews mathematics, and uses not structure The Crab Nebula. By Sill)on Mi.tton. the layman and complex mathematical a single equation. The reader need Pp. 194. (Faber and Faber: London; texts for the professional astronomer. only be moderately numerate, so that Scribners: Totowa, New Jersey, 1979.) Twenty years earlier George Gamow's he can apprecia.te the large powers of £6.50; $14.95. book The Birth and Death of the Sun ten involved in any branch of astro­ had served a similar purpose, but by physics. 1967 this was seriously out of date in THE 900th birthday of the Crab Nebula The decision to exclude mathematics detail. The first edition of Meadows' was celebrated by radio astronmers in reduces the astronomy of the Crab to book gave a clear account of the July 1954. At that time it was almost less than half of the total of astronomy; observed properties of stars and the the only celestial object, apart from the and further choices have been made. manner in which they are obtained. It Sun, where a close link between optical Mitton has chosen to make the book then discussed the principles under­ and radio astronomy had emerged. In readable, straight through, for anyone lying the structure of stars, the source these days, when such links have ap­ with an undergraduate level of physics of the energy radiated from stellar sur­ peared throughout astronomy, the or astronomy. Others, with less expert faces, the manner in which this energy Crab still has a unique importance, and knowledge, will enjoy at least the his­ travels from the centre to the surface annual celebrations of the supernova torical accounts of the supernova of a star, and the physical state of the explosion would still be appropr-iate. explosion, gleaned from Chinese and matter inside stars. The remainder of Geoffrey Burbridge once said that Japanese records of the "guest star", the book was concerned with the evolu­ astronomy could be divided into two and the more recent history of dis­ tion of stars from their birth as dense parts : the astronomy of the Crab coveries-notably of the pulsar which condensations in interstellar gas clouds, Nebula and the astronomy of every­ remains the centre of the nebula, pro­ through the major part of their life as thing else. There are indeed links viding the powerhouse for the energy main sequence stars (the present state between the Crab and almost every­ to keep the nebular shining. For the of the Sun) and subsequently as red thing else in astronomy, so that a dis­ physicist, the -exposition of the basic giants, to their death as white dwarfs, course on the Crab can he used as an concepts of degeneracy in white dwarfs possibly after a supernova explosion. introduction, for example, to astron­ and neutron stars, and of superconduc­ It was then difficult to see how our omy, stellar evolution, cosmology and tivity, will have a strong appeal, as they knowledge of stellar evolution could be interstellar matter; including the Crab show most clearly the connection be­ treated in a significantly clearer manner Pulsar extends the list to the physics of tween terrestrial and celestial solid­ without the introduction of mathe­ condensed matter, high energy electro­ state physics. matical detail, which was completely dynamics, superconductivity, and many Mitton is an enthusiast. In conveying absent frt'm Meadows' book. other aspects of quantum physics. his enthusiasm he does sometimes over­ The first edition has now been This microcosm of astrophysics can step the mark, in such purple passages revised to take account of developments therefore he used as a general introduc­ as his description of synchrotron radia­ in the suhject. Most of the book has tion to astronomy, which should appeal tion : "photon screeches from very been photographically reproduced from to any scientist and which may per­ energetic electrons as they wrap them­ the first edition and in most places it is suade some that astronomy is a very selves round the ambient magnetic possible to sec where ,·hangcs have been useful means of education in basic field". He refers -to the giant pulses made hrcause of a slight variation in physics. Popular books on astronomy from the pulsar as "jumbo", he tells us IC Macmillan Journals Ltd 1979 .
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