Red Sky

SG-1 travel to K'Tau (P39-865) and discovers that the sun has been shifted to the infrared end of the spectrum. All life on the planet is doomed, and SG-1 are responsible. The planet's inhabitants are Norse people and worship the Asgard, and believe that the reddening sky is a sign from their Gods. In reality, the event is a solar reaction caused by SG-1's wormhole that spells death for the planet and its people.