An unusual series of episodes, in which the lower (and perhaps all) latitudes of the Earth were covered by snow and ice, has geologists rather puzzled. The duration of the interval in which these events occurred was only some 200 million years of Earth history in the late Precambrian, making the occurrences rather unique. The evidence for these low-latitude glaciations and some of the implications for Earth's climate, atmospheric, and celestial-orbital history will be presented.

After the lecture, at 9:00, the Student Astronomical Society will hold a free open house including telescopic viewing from the Angell Hall observatory and planetarium shows on the third floor of Angell Hall. For more information click here .