Unit 2
Tools of the Astronomer

Astronomers can rarely interact directly with the objects they study. Instead, most astronomers can observe only at a distance (and that distance is usually very great) the electromagnetic radiation emitted by the objects they wish to study. Consequently, astronomers must be able to understand and interpret the information carried by electromagnetic radiation. This unit will introduce you to the properties of electromagnetic radiation, and the instruments astronomers use to detect and amplify it.