Key Ideas and Terms

2-1 Light Travels through Empty Space at a Speed of Nearly 300,000 km/s

2-2 Glowing objects, like stars, emit an entire spectrum of light

2-3 An object’s temperature is revealed by the most intense wavelength of its spectrum of light

2-4 An object’s chemical composition is revealed by the unique pattern of its spectrum of light

2-5 An object’s motion through space is revealed by the precise wavelength positions of its spectrum of light

2-6 Telescopes use lenses, mirrors, and electronics to concentrate and capture incoming light for study