The cover of A More Perfect Heaven: How Copernicus Revolutionised the Cosmos by Dava Sobel

One of the first things the audience learnt in this engaging discussion between Robyn Williams and Dava Sobel, the author of Longitude and of Galileo’s Daughter among other books, is that Copernicus was a kind man. This is unlike Newton, who was a nasty person (a paraphrase of Robyn Williams’ one word description). Among Copernicus’ few surviving letters a number defend his housekeeper whom he was under constant pressure to send away. As well, during the three years he spent administering transactions among peasants he showed compassion, for example in one instance he reduced the rent of an elderly couple with no children and even gave them a horse.

Of course, Nicolaus Copernicus was the man who moved the Sun to the centre of the solar system at a time when the accepted belief was that the Earth was the centre and all celestial bodies revolved around it. This belief matched the observation that the Earth appeared to be a stable and motionless platform while the Sun, the planets and the stars rose daily in the east and set in the west and so were circling around the Earth. In addition, there were theological foundations to this belief: the Earth was considered a pit of change and decay, a real den of iniquity, while the heavens were perfect. So how could the Earth be placed into the heavens?

The new view of the Solar System with the Sun at its centre, from On the Revolutions of the Celestial Spheres by Nicolaus Copernicus. Courtesy Wikimedia Commons

Copernicus did not dare to publish his work as he was afraid of being criticised, especially by people using passages in the Bible against him such as the call by Joshua for the Sun to stand still – if the Sun were stationary why would Joshua ask it to stop moving? All this changed when Copernicus was visited by a young mathematician from Wittenberg, Georg Joachim Rheticus. Somehow during his two year stay Rheticus persuaded Copernicus to publish.

The records do not tell us what happened between the elderly Copernicus and the young mathematician who wanted to use the work of Copernicus to improve the practice of astrology. To fill in the gap, Dava Sobel includes a play in the book that imagines what happened between the two men. She told Robyn Williams that writing dialogue was much harder than writing ordinary text and had to be carefully refined.

I had enjoyed reading the play in the book as it was witty and it made Copernicus seem much more real than from just reading the historical facts. However, when two short extracts from the play were read by the two of them (Robyn Williams has acting experience from his student days) it took on an extra dimension that was most impressive.

Listening to the play and to the discussion generally it struck me what a big and difficult step that Copernicus had taken. To us with the advantage of hindsight and the knowledge of many scientific developments that have taken place since Copernicus’ time it is obvious which bodies are moving in relation which other ones. It was not so obvious at a time when there was no understanding of inertia or the dynamics of moving bodies that was to be developed later by the Italian scientist Galileo, who was born two decades after the publication of Copernicus’ famous book. Hence it must have been difficult for Copernicus to explain why we do not feel motion if it is the Earth rotating and revolving around the Sun. Or, even if the Earth moves, why there is no huge wind from a stationary atmosphere.

This fascinating discussion was recorded and maybe will be played in the near future on the ABC Science Show. Listen out for it and in the meantime read the book. It’s highly recommended.

The 'Transit of Venus' book cover

In 2012, on 5 or 6 June (depending on location) people across the globe will have the opportunity to witness one of the most famous of astronomical events, a rare transit of Venus. This event takes place when, as seen from Earth, Venus crosses in front of the Sun. It occurs in pairs eight years apart and there is approximately one pair during each century. The transit of 2012 follows the one in 2004 and will be the last chance in our lifetime to see a transit for there will not be another until 2117.

The Observatory’s former long–serving Curator of Astronomy, Dr Nick Lomb, has prepared a book (available for purchase online or at Sydney Observatory, Powerhouse Museum or good bookshops) that is the essential companion to the 2012 transit. It provides detailed information on when, where and how to observe this exciting event. More importantly, it explains its significance and relates the stories of the exciting and adventurous journeys undertaken by astronomers to observe transits in past centuries. One of these was that of Captain James Cook to observe the transit of 1769 from Tahiti, a journey that led to the European settlement of Australia.

Observations of Venus moving in front of the disc of the Sun in 1874, by Henry Chamberlain Russell, the director of Sydney Observatory. Powerhouse Museum Research Library

The book is extensively illustrated with rarely seen archival images of earlier transits plus stunning photographs from the 2004 transit. These are complemented by modern NASA images of Venus.

Description
The transit of Venus across the Sun in June 2012 will be the last chance in our lifetime to see this rare planetary alignment that has been so important in history.

Rich in historical detail and cutting edge science, along with practical information on how and when to view the transit, ‘Transit of Venus’ is the must-have companion to this extraordinary astronomical event.

An engraving of Captain James Cook who observed the 1769 transit of Venus from Tahiti. Brian Greig collection.

From Johannes Kepler’s first prediction of a transit of Venus in 1631, to Captain Cook’s 1769 transit expedition to Tahiti (which led to the European settlement of Australia), and on to our 21st-century quest to find distant Earth-like planets using the transit method, astronomer Nick Lomb takes us on a thrilling journey of exploration and adventure.

Endorsements
‘This is exactly what a great astronomy book should be: comprehensive, highly informative yet very accessible for lay readers, and beautifully illustrated to showcase the glory of the heavens.’
– Dr Kevin Fewster, Director, National Maritime Museum and Royal Observatory, Greenwich, UK

‘With this superb and lavishly illustrated book, astronomer Nick Lomb has provided the complete guide to Venus transits past and present. Essential reading for everyone.’ – Dr Professor Fred Watson AM, Astronomer-in-Charge, Australian Astronomical Observatory, Coonabarabran

‘Everyone should see the transit of Venus in June 2012,since it is the last chance until 2117. And everyone should read Nick Lomb’s fascinating book, which beautifully and dramatically highlights both the history and scientific importance of the transit of Venus.’— Professor Jay M. Pasachoff, Vice Chair, Historical Astronomy Division of the American Astronomical Society

Nick Lomb at the site in Goulburn from where a Sydney Observatory team observed the 1874 transit

About the author
Dr Nick Lomb was Curator of Astronomy at Sydney Observatory for thirty years (1979-2009). He continues to work as a consultant astronomer for Sydney’s Powerhouse Museum and for Sydney Observatory. He is the author of the ‘Australasian Sky Guide’, published annually by the Powerhouse Museum, as well as several books on astronomy including ‘Astronomy for the Southern Sky’ (1986) and ‘Observer & Observed: A pictorial history of Sydney Observatory and Observatory Hill’ (2001). He led Sydney Observatory’s observations and celebrations of the transit of Venus in 2004.

Details
‘Transit of Venus: 1631 to the present’
By Nick Lomb

Published November 2011
ISBN 9781742232690
NewSouth & Powerhouse Museum, 232pp, HB, 230 x 230mm
RRP AU$49.95
110 images, full colour throughout

Table of contents
Introduction
A spot of unusual magnitude: 1639
Frozen plains and tropical seas: 1761
Venus of the South Seas: 1769
Capturing the transit: 1874 and 1882
Space-age transit: 2004
Observing the 2012 transit
Glossary
Bibliography
Acknowledgements
Index

Nick Lomb’s beautifully designed and illustrated book brings the history and importance of the transit of Venus alive with his engaging and lively text. Available for purchase online or at Sydney Observatory, Powerhouse Museum or good bookshops.

A fascinating book to guide your exploration of the southern night sky

The ‘Australasian sky guide book’ is written by astronomer, Dr Nick Lomb, and produced annually by Sydney Observatory.

Each edition contains a wealth of information for keen stargazers, and includes monthly information for 13 months from December to December, inclusive.

It contains sky maps for each month making it the celestial equivalent of a street directory, as well as other astronomical information to add interest and understanding to your skygazing.

For every day of every month, there is information about:
- the rise and set times of Mercury, Venus, Mars, Jupiter and Saturn
- sunrise and sunset times
- moonrise and moonset times
- times of high and low tides

You can buy the ‘Australasian sky guide’ at good bookshops and at Sydney Observatory or the Powerhouse Museum for $16.95. You can also buy it online (additional charges apply).