Over the Moon

It’s much too thin for us to breathe, but there is an atmosphere on Saturn’s icy moon Rhea. For the first time a spacecraft, NASA’s Cassini, has captured molecules from an atmosphere other than the Earth’s. Ben Teolis (Grad ’07), who earned his doctorate in engineering physics from UVA, and professors Raul A. Baragiola and Robert E. Johnson found that Rhea’s atmosphere is infused with oxygen and carbon dioxide—though the atmosphere itself is about 5 trillion times less dense than Earth’s. “The new results suggest that active, complex chemistry involving oxygen may be quite common throughout the solar system and even our universe,” Teolis says.