Did you know that sunlight travels to us at 186 thousand miles per second, or that on Mercury, a day is twice as long as a year? Or that the Aztecs saw Venus as the twin brother of the sun and that a single carat of moon rock sold at auction for more than four hundred thousand dollars?
Jenni talks to Dava Sobel, author of Longitude and Galileo's Daughter about her new book: The Planets.
The Planets by Davd Sobel, published by Fourth Estate Ltd - ISBN:1857028503
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