Taranis

Taranis is a planet in the Pegasus galaxy. It was a former colony of the Atlanteans, as evidenced by the outpost left behind with a Dialing Device like the one used in Atlantis, and possessing a shield being powered by geothermal energy. During the War with the Wraith, Taranis served as a drydock for the Ancient fleet, with one ship, the Hypafaralkus, being left behind after the Atlanteans fled back to Earth. Eventually, Taranis was repopulated by Humans who began to study the Atlantean technology left behind, and using the shield to protect themselves from the Wraith. However, the shield's use of geothermal energy caused the dormant supervolcanoe the base was in to become active. The Atlantis Expedition came to Taranis, and help most of the people escape, but the Stargate was destroyed, and a massive dust cloud emerged from the volcanoe, rendering the planet uninhabitable for many years.