What is light? Most astronomical objects are too far away to measure
directly. Light is the messenger of the Universe, carrying with it
information about objects as near as the Moon and as far away as the
most distant objects in the visible Universe. In this lecture we will
review the basic properties of light, the electromagnetic spectrum, the
inverse square law of brightness, and the Dopper Effect. Recorded 2007
Oct 22 in 1000 McPherson Lab on the Columbus campus of The Ohio State
University.