BOOK REVIEWS

THE PLANET NEPTUNE

P A T R I C K M O O R E Ellis Norwood £19.95 144 pages

This book gives a valuable account of the discovery of planet Neptune and a summary of our

present knowledge about this member of the Solar System; it concludes speculatively on the post

sible existence of other remote planets even more distant from the Sun. Since much revision of

our ideas will undoubtedly take place following a successful Voyager 2 fly-past in August 198q one

suspects that the book may well be rapidly confined to an upper shelf in the astronomer's bookcase,

save for its historical value. However, this is partially unfair. The more interesting and

lasting aspects of the book include a detailed recounting of the story of the discovery of Neptune

with details of the events both bearing up and subsequent to the Berlin observations in 1846,

arguably the final jewel in the crown of Newtonian gravity. There is indeed more to this episode

of history (and politics) than is commonly known, and many other popular treatments of this often

brush over a fascinating and salutory story.

The book also serves to emphasize the limitations of our ground-based observational knowledge

of the Solar System by recalling various claims about ring and satellite systems which failed to

stand the test of time, and demonstrates how such Voyager-type missions are essential for the

enhancing of our understanding about the Solar System.

Roughly half the text is devoted to the historical aspects and includes reproductions of the

relevant correspondence from the epoch of discovery which are of great interest, especially to

historians of astronomy. In particular the part played by the Astronomer Royal, Sir George Airy,

that giant of the nlneteenth-century astronomical world, is fully documented.

The last part of the book is concerned with our knowledge of the physical nature and pro-

perties of neptune and its satellites; these chapters are short in length, containing data and

ideas surely to be improved upon by the end of 1989. It is to be hoped that this first edition

will quickly be followed by a second embodying these new results.

Fraser G o r d o n

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