Lesson Three : Types of Radiation
Our eyes observe electromagnetic radiation when it is emitted from sources of visible light. Every object in the universe emits some form of electromagnetic radiation. Just as we use our eyes to perceive and gain information about the world around us, astronomers study the radiation emitted by various objects in space to learn about the objects themselves.Radio waves are one of the most useful forms of radiation coming to us from space. These waves tell us many things about space, but before we can understand what they tell us, we must understand how they are produced and what produces them.