Stephen James O'Meara is author of several highly acclaimed books, including others in the celebrated Deep-Sky Companions series. He is well known for his precise drawings of astronomical objects as seen through the telescope, his engaging and informative writing style and for his remarkable skills as a visual observer. Steve spent much of his early career on the editorial staff of Sky and Telescope, before joining Astronomy magazine as its Secret Sky columnist and a contributing editor. An award-winning visual observer, he was the first person to sight Halley's Comet on its return in 1985 and the first to determine visually the rotation period of Uranus. One of his most distinguished feats was the visual detection of the mysterious spokes in Saturn's B-ring before most spacecraft imaged them. Amongst his achievements, Steve has received the prestigious Lone Stargazer Award, the Omega Centauri Award and the Caroline Herschel Award. Asteroid 3637 was named O'Meara in his honor by the International Astronomical Union. In his spare time, Steve travels the world to document volcanic eruptions. He is a contract videographer for National Geographic Digital Motion and a contract photographer for the National Geographic Image Collection.

David H. Levy is one of the most successful comet discoverers in history. He has discovered 22 comets, nine of them using his own backyard telescopes. Together with Eugene and Carolyn Shoemaker at the Palomar Observatory in California he discovered Shoemaker-Levy 9, the comet that collided with Jupiter in 1994 producing the most spectacular explosions ever witnessed in the solar system. He is involved with the Jarnac Comet Survey, and Science Editor for Parade magazine, and contributing editor for Sky and Telescope. He has been awarded five honorary doctorates, and asteroid 3673 (Levy) was named in his honor. His other recent books include David Levy's Guide to Observing and Discovering Comets and David Levy's Guide to Variable Stars (Cambridge University Press).