A comprehensive book explaining the use of the 2102D star finder, and the many applications it offers in planning navigation. Its numerous examples and diagrams make it a most definitive treatment. In addition to a description of the star finder and its basic use, the book covers: brightness and color of stars, planet identification, choosing optimum star-moon-planet combinations, choosing time between sunlines and running fixes, and emergency steering. This book is an indispensable companion to the star finder itself.