21. There is also a Celestial Navigation Course for instruction in navigating by the stars. 22. The term chronometer is also used to describe a marine chronometer used for celestial navigation . 23. It may involve water temperature, currents and celestial navigation . 24. The navigation devices also malfunctioned, but Perka's Navy training allowed him to use celestial navigation . 25. Fifty-eight selected navigational stars are given a special status in the field of celestial navigation . 26. In 1984, along with Geoffrey Lewis and David Campbell, Levin created the story-telling group Celestial Navigations . 27. However, with the advent of GPS, student navigators were no longer taught celestial navigation or LORAN. 28. For navigators near the equator celestial navigation is simplified since the whole celestial sphere is exposed. 29. Before the introduction of the compass, celestial navigation was the main method for navigation at sea. 30. "I teach them celestial navigation , " he says.
