Laurence Marschall, Ph.D., is the W.K.T. Sahm Professor of Physics at Gettysburg College where he teaches courses in astronomy, physics and science writing. He received his bachelor’s degree at Cornell University and his doctorate at University of Chicago. He writes a regular column on science books of note for Natural History magazine and is a contributing editor of Smithsonian Air and Space. He also contributes annual astronomy updates to the World Book Encyclopedia. He serves as deputy press officer of the American Astronomical Society. In addition to more than 40 articles in professional journals, Marschall has written for publications such as Sky and Telescope, Astronomy, Natural History, Discover, Harper’s, Newsday and the New York Times Book Review.