Astronomy 1021 Study Guide - Radio Astronomy, Subatomic Particle, Adaptive Optics
Document Summary
Light waves slow down when they hit your eye because light generally travels more slowly through denser matter than through air: the change in speed causes the wave the bend, this is known as refraction. The place where the image appears in focus is called the focal plane of the lens. Any device that records light is called a detector. The light collecting area tells us how much total light the telescope can collect at one time. Angular resolution is the smallest angle over which we can tell that two dots or two stars are distinct. The ultimate limit to a telescope"s resolving power comes from the properties of light: since light is an electromagnetic wave, beams of light can interfere with one another like overlapping sets of ripples on a pond. The interference limits a telescope"s angular resolution even when all other conditions are perfect. Most observations fall into one of three basic categories : imaging.
