Professor Neil F. Comins is on the faculty of the University of Maine. He earned a bachelor's degree in engineering physics at Cornell University, a master's degree in physics at the University of Maryland, and a Ph.D. in astrophysics from University College, Cardiff, Wales. Dr. Comins took over the authorship of Discovering the Universe in its Fourth Edition, following the death of William Kaufmann. He is also the author of Discovering the Essential Universe and Discovering the Universe: From the Stars to the Planets. Dr. Comins has also written bestselling books for general audiences, including What if the Moon Didn't Exist?, Heavenly Errors, The Hazards of Space Travel, and What if the Earth Had Two Moons?