For 12 years, the people of Talthus knew that a dark star would pass close enough to their sun to cause it to flare and engulf their world. They built three ships, including the Stromos, to carry survivors in stasis to a new homeworld called Ardena, a journey that would take hundreds of years. A lottery was held to select the passengers that would preserve the last of their race. When the Stromos crashed on P2A-347, SG-1 helped to restore its power and to revive and relocate the last survivors of Talthus.
Episode Reference: Lifeboat