Horizons

This revised and updated text has two goals: to show students their place in the universe - not just their location, but their role as planet dwellers in an evolving universe - and to show how science works, and how scientists depend on evidence to test hypotheses and build confidence in theories.

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This revised and updated 6th edition has two goals: to show students their place in the universe - not just their location, but their role as planet dwellers in an evolving universe - and to show how science works, and how scientists depend on evidence to test hypotheses and build confidence in theories. Essentially, the book can be understood by a principle, organizing theme: the interplay of evidence and hypothesis. Through a discussion of this interplay, it provides not just a series of facts, but a conceptual framework for understanding the logic of astronomical knowledge. A good example of this is how a survey of the solar system in chapter five leads to theories that explain the origin of the solar system, which is followed by further evidence in chapters six to nine that helps students test and generalize theories. At a different level, the paragraphs that discuss Jupiter's rings show how basic observations allow us to propose theories for the origin of the ring particles.