About the Author

Ray Spangenburg and Diane Kit Moser have been writing about science for more than 20 years. They are the authors of more than 50 books, including Facts On File's The History of Science set. Former journalists and editors, they have written for numerous magazines, including The Scientist, Science Digest, Space World, and Final Frontier.|||Harry Henderson is a professional writer specializing in technical and reference works for adults. Among his numerous publications are Privacy in the Information Age, Gun Control, and Capital Punishment, Revised Edition, all of which are part of Facts On File's Library in a Book series. He lives in El Cerrito, CA