Here is a unique and fascinating reference book for every serious deep-sky observer! Entries for each of more than 500 deep-sky objects provide far more than the usual astronomical data ? they also detail, in every case, the most interesting facts. Physical factors, astrophysical information, evolution, unusual features, the list is endless. The objects are all listed in NGC order.  Astronomers can now get an insight into exactly what they are looking at, to add a new level of insight and enjoyment to deep-sky observing.