SLAS Regular Meeting
Friday, March 18, 2011
7:30pm
McDonnell Hall
Washington University

A Daylight Comet Next September? What Makes A Comet Bright?

by

Dr. Joseph Marcus, M.D.

A new comet has been discovered that will pass between the Earth and the sun at the end of September 2011. If the right conditions develop, the comet could become bright enough to be seen during the daytime. But the brightness of new comets has been notoriously difficult to predict accurately. Dr. Marcus will explain what makes a comet shine and what factors determine how bright a comet will become. He will also discuss something about the composition of comets. He will explain how we can tell what a comet is made of, from a distance typically millions of miles away.

Dr. Marcus is an avid astronomer with particular interest in the study of comets. In addition to observing them, he was editor of The Comet News Service, a quarterly and special-edition publication of the McDonnell Planetarium in the mid-seventies and early eighties.