Uses a discovery approach which encourages readers to be active rather than passive learners. Organized in the way astronomy developed-from observations to an understanding first of the solar system and later of stars and galaxies. A separate Activity Kit features experimentation and measurement projects in order to obtain direct experience in the scientific gathering and analyzing of data. In this edition, the art program has been expanded to include full color photos plus computer generated multicolor diagrams which help clarify complex concepts. Contains a completely rewritten and updated discussion of the planets and a new Earth/Moon chapter.