Penumbral Lunar Eclipse Tonight

by Anne Verbiscer

Anne Verbiscer is a Research Associate Professor at the University of Virginia. She studies the surfaces of icy bodies in the outer Solar System and has been involved with the Cassini mission to Saturn since 2007. Currently a visitor at Southwest Research Institute, she has been enjoying the past year living in the mountains above Boulder, Colorado.

At 8:37:51 UTC on July 7th, the Moon will be eclipsed, but just barely, by the Earth's penumbra for about two hours. This penumbral eclipse, the second of four lunar eclipses in 2009, will be so slight that the difference in brightness between the eclipsed and uneclipsed Moon will be invisible to the unaided eye.