2025-08-03 –, Kuiper Space Sciences Lecture Hall (308)
The ability to efficiently detect faint fast moving asteroids requires a knowledge of the brightness of the night sky. We are using Sky Quality Meters (SQMs) located on Mt. Lemmon, Mt. Bigelow, Kitt Peak, the Cosmic Campground IDSS, and other locations to measure night sky brightness. We have developed techniques to detect clouds and thus select the best astronomically dark nights. These data are used to measure sky brightness changes due to increasing solar activity, periodic changes as the Earth orbits the Sun, as well as dynamic events caused by coronal mass ejections or other changes in the solar wind. An interesting new result is that there appears to be a sky brightness minimum a few weeks after the vernal equinox and a maximum a few weeks after the autumnal equinox.
Dr. Al Grauer is an observational astronomer with 52 years of experience. He has observed at professional observatories in Arizona, Hawaii, Chile, Australia, and Louisiana. He was a Professor of Astronomy at the University of Arkansas at Little Rock for 30 years and is currently employed by the Catalina Sky Survey at the University of Arizona. As a member of the Catalina Sky Survey team he discovered 2 comets and is co-discoverer of tens of thousands of asteroids. He has published more than 75 papers in peer reviewed scientific journals. His wife, Patricia A. Grauer, and he collected data and wrote the application which resulted in the Cosmic Campground becoming the first International Dark Sky Sanctuary in North America. He continues to study night sky brightness and has published two scientific papers on the subject. His podcast “Travelers In the Night” has aired more than 6,600 times on more than 60 radio stations. It has more than 860,000 plays on the internet.