Chasing the Sun: The Epic Story of the Star That Gives Us Life

  • Richard Cohen
Simon & Schuster/Random House: 2010. 704 pp/608 pp. £30/$35 9780743259286 | ISBN: 978-0-7432-5928-6

To humankind, the Sun is the most important body in the Universe. It has been deified and associated with fecundity and eroticism, it pervades literature, art and film, and it influences our daily moods. Studies of the Sun motivated revolutionary changes in scientific thought in the twentieth century — including quantum mechanics and general relativity — and today its workings still constitute a most important branch of astronomy and astrophysics. To write yet another work about our nearest star is a formidable challenge that author Richard Cohen takes up with aplomb. Chasing the Sun paints a fascinating and far-reaching scene that incorporates nearly all aspects of solar phenomena.

Many dates owe their origins to the Sun's movements — even the start of the UK tax year.

Cohen touches on a range of histories of Sun-related myths, religions, superstitions and traditions. From Babylon, Egypt and Greece to China, Persia, India, Peru, Arabia and Japan, ancient cultures established observatories to chart the motions of the Sun, the Moon, planets and stars. Because the annual shift of the Sun's path across the sky is pertinent to the survival of agrarian societies, these cultures developed calendars to determine when crops should be sown.

Louis XIV of France named himself the Sun King to bolster his authority. Credit: AKG-IMAGES

The Sun was a god to many civilizations, and rulers often derived their authority by asserting that they were descended from it. Cohen describes the influence of the Sun on architecture, art, music, literature, poetry and even politics. He discusses how our understanding of the physical nature of the Sun has developed, and, to a lesser degree, how that knowledge has advanced our understanding of physics.

The Sun did contract from the gas and dust of the interstellar medium, but that took just 10 million years.

The narrative is liberally sprinkled with personal anecdotes, which is largely what makes the book so enjoyable. Cohen describes how, early in the morning of the summer solstice of 2005, he ascended Mount Fuji in Japan to see the sunrise with the words “You run and you run to catch up with the Sun” from Pink Floyd's song Time running through his ears. At the summit, he bathed in the colours of the rapidly changing skyline — indigo, purple, ochre — and, when the full glare of the Sun struck home, he understood why we say something 'dawns' on us. The book is also peppered with gems of information, such as the origins of the expressions high noon, high seas and plain sailing.

Much is said about time-keeping, and how many dates owe their origins to the Sun's movements: pagan festivals, Christian festivals, even the start of the UK tax year on 6 April. Cohen also goes into the dangers of sunlight; for example, he relates how, after the 1999 solar eclipse in England, doctors in a London hospital reported that they could pinpoint the precise phase at which a patient had stared at the Sun from the shape of the 'sickle' damage to his or her retina.

This book is no stolid scholarly treatise. Cohen is mainly a storyteller, who, after more than seven years of research, has amassed a prodigious amount of information and organized it into an entertaining narrative. However, in not wanting to detract from the main point of his tale, he occasionally oversimplifies matters — especially those scientific ones for which veracity is sometimes left behind. For example, at the start of the book the casual reader might be led falsely to believe that the Sun is now contracting, later to fade into a red giant. This is contradicted nearly 600 pages later by a paragraph offering a more accurate view. The Sun did initially contract from the gas and dust of the interstellar medium, but that took just 10 million years. Since then and for almost all of its existence — some 4.6 billion years so far — it has been expanding, and will continue to do so at a steadily accelerating pace for nearly 6 billion years more. It will then expand rapidly into a highly luminous red giant, albeit with a lower surface temperature, before finally condensing to a white dwarf.

Despite shortcomings such as these, Chasing the Sun is a marvellous read.