English: The detection of very-high-temperature volcanism—hotter than any terrestrial lavas currently erupting—is one of the most spectacular discoveries by the Galileo mission at Io. The images are of an area called Tvashtar and show curtains of lava fountains erupting on the surface. They were taken by the Galileo spacecraft on November 26, 1999. The active region is approximately 25 km (15.5 miles) long and 1 km (0.6 mile) high. The radiant energy emitted from the lava curtain was so intense that it overpowered the camera's detector and it is registered only in white.