9781422283356

Astronomy , the study of all that lies beyond the Earth’s atmosphere, may be the most ancient of the sciences. Its roots lie in our desire to order and understand our lives. Almost certainly you will have looked up at the night sky at some time or another and thought about what you could see there. In doing so you are no different from the very first people, who must also have looked with wonder on the twinkling, unreachable lights far above their heads. The path towards an understanding of what goes on beyond our tiny planet has been a long one and we haven’t reached its end yet. In this book we will retrace that path and try to see where it may be leading. Many great people have walked it, all of them pushing our knowledge of the Universe further and further out. Today, we are reaching for the beginning of time and the edge of space. HEAVENLY CLOCKS Before people could write down their ideas they knew about the phases of the Moon and the changing positions of the Sun and stars. The constant regular motion of the Sun, Moon and stars were our ancestors’ clocks, and because they were so important they were thought to have great powers. For the peoples of many societies these heavenly bodies were gods. Six thousand years ago, for example, people in northern Europe built long graves, called barrows, which were aligned towards the point on the horizon where bright stars were known to rise. The positions of the stars guided people in their day-to-day lives. Science and religion were linked in the ancient world and an astronomer-priest was a powerful man in his society. By closely observing the sky he could appear to foretell the future. When the star Sirius rose in the east just before dawn, for example, the Ancient Egyptians knew that the River Nile was about to flood. Chapter HIGHWAY TO THE UNKNOWN

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