Life on Mars, the Star of Bethlehem, & Other Milky Way Mysteries

In 12 delightful chapters, astronomer Kidger takes us on a tour of the solar system, addressing an array of fascinating questions, not all of which he can answer. For example, Kidger is unable to conclude for what ultimate purpose Stonehenge was built, noting that since construction occurred over a 1,500-year period, the purposes no doubt changed over the centuries. (He does deftly debunk some common myths about the site.) The author thoroughly entertains while providing a great deal of intriguing material on the Star of Bethlehem, the possibility of life on Mars and whether Pluto should be considered a planet or merely a trans-Neptunian object. Kidger is also superb at explaining how scientists can learn so much about astronomical objects without ever leaving home, and he writes eloquently about why we must continue to explore the heavens via manned space flight. Finally, he explains why we needn't worry—at least not for many hundreds of years—about a killer asteroid smashing into the Earth. What we probably should worry about, he says, is a runaway greenhouse effect fueled by human activity that might bring about planetary change similar to what probably happened naturally on Venus. Kidger's playful but informed style makes the book a joy to read. 63 four-color images not seen by PW . (June)