ASTR 1210 Lecture Notes - Lecture 1: Charge-Coupled Device, Yerkes Observatory, Diffraction
Document Summary
Speed of light = largest speed in the universe (300,000 km/s) Light is a particle called a photon, has no mass (that"s why it"s so fast) Light is the means of connecting us to cosmos/everything. Scientists want to collect more light- allows more to be seen. Seeing faint seeing far going back in time. Explanation: seeing fainter means you can see further away, and since things farther away take more time to be seen you"re basically looking back in time. Improves angular resolution (defined as the smallest angle over which we can tell two dots apart) The angle is proportional to the diameter over the distance (= ) Brittanica definition: the smallest angle between close objects that can clearly be seen to be separate. Diffraction limit smallest angle that a telescope can see is inversely proportional to the diameter of the telescope. Light-collecting power is proportional to the area of the telescope r^2 = (d/2)^2 = d^2)/4.