Now in a beautifully redesigned, two-color landmark 20th edition, this combination star atlas and reference guide has no match in the field.First published in 1910, prompted by the appearance of Halley's Comet, Norton's owes much of its legendary success to its unique maps, arranged in slices or gores, each covering approximately one-fifth of the sky. Accompanying and complimenting the charts is a succinct descriptive and tabulated accounting of astronomical knowledge and data.In this new edition the text and tables have been revised and updated to account for the new and exciting developments in astronomy. The star maps themselves were plotted using advanced computer techniques, yielding outstanding accuracy and legibility. Every celestial object visible to the naked eye is included--stars to magnitude 6, star clusters, and galaxies, as well as other celestial objects. Presented with an authority that has stood for generations, observation hints, technical explanations, and pointers to specialized information sources, make this the only essential guide to the night sky.