Doug Taron, PhD, Curator of Biology and Vice President of Conservation and Research at the Peggy Notebaert Nature Museum, talks about several Midwest species of butterflies--including monarchs--that have seen their numbers decline. Audrey Fischer from the Chicago Astronomical Society, Mark Hammergren from the Adler Planetarium, and David Blask of Tulane University School of Medicine explain why light pollution not only keeps us from seeing the stars at night, but could be harmful.