Explores the speed of light, time dilations, the twin paradox, equivalence of acceleration and gravity, and the curvature of space-time. The Tools of Astronomy Astronomers are the only scientists who do not possess and manipulate the objects they study. An overview of the electromagnetic spectrum, from gamma rays to radio waves, and the types of information provided by individual bands is presented. The program focuses on the major types of telescopes used by astronomers. Explains the spectrograph, which enables astronomers to determine a star's composition.
Astronomers explain how the strength of spectral lines is related to stellar temperatures.
Through the Doppler effect, a star's spectrum reveals clues about its motion with respect to Earth and its rotation rate. The Sun Explores how differently we study the sun than other stars. Discussed are the space-based observatories and how much has been discovered about the sun, its core, and the various zones and how the layers actually get hotter as they go upward from the core of the sun. Explains helioseismology, the study of vibrations in the visible surface of the sun that reveal the underlying hidden structure. 9 Stellar Properties Explains the basic technique of parallax and how it is used to measure distance.