Lecture 22: Light the Messenger
b'What is light? Most astronomical objects are too far away to measure\\ndirectly. Light is the messenger of the Universe, carrying with it\\ninformation about objects as near as the Moon and as far away as the\\nmost distant objects in the visible Universe. In this lecture we will\\nreview the basic properties of light, the electromagnetic spectrum, the\\ninverse square law of brightness, and the Dopper Effect. Recorded 2007\\nOct 22 in 1000 McPherson Lab on the Columbus campus of The Ohio State\\nUniversity.'