During "Galileo's" encounters with Io between October 1999 and October 2001, the spacecraft observed Pele on three occasions using its camera and infrared spectrometers while the volcano was on Io's night-side. The cameras revealed a curved line of bright spots along the margin of the Pele patera (a term used for volcanic depressions on Io, akin to calderas). Within the east-west dark band along the southeastern portion of the patera, a large amount of thermal emission was observed, with temperatures and distribution consistent with a large, basaltic lava lake.