Earth’s southernmost active volcano may also be its most remote. Rosaly Lopes and Michael Carroll recently spent a few frigid days on the slopes of Antarctica’s Mount Erebus. What they learned may help us understand volcanoes on other worlds. Emily Lakdawalla shows us stunning new, close-up images of Saturn’s rings. Bill Nye says a LightSail solar sail prototype has gone on display in a London museum. How could black holes help answer a space trivia contest question about Earth and Saturn? Also, an encore presentation of a visit with the late Gene Cernan, last astronaut to walk on the moon.