Red Sky

Red Sky is the fifth episode of the fifth season of Stargate SG-1.

Plot
SG-1 has a rough landing when they dial to K'tau: Carter explains she had to override the safety protocols of the dialing computer when the Gate wouldn't lock on. They meet a 16th century (or similar period) society that worships the god of the sun and rain Freyr, one of the Asgard. Village elder Elrod is happy to meet SG-1, but one citizen, Malchus, is suspicious. The "elves" (as they are called since they came through the Gate, here called an Annulus) might as well bring mischief. Seconds later, the sun goes red. Carter realizes the sun (referred to as the "Eye of Odin") of the planet has been passed through by the wormhole, which picked up traces of a heavy element and deposited it in the sun's mass, shifting the light emitted towards the infra-red end of the spectrum. Suddenly, photosynthesis has become impossible and the plants will die soon, which is certain destruction for the life on that planet. SG-1 go to a worship service, where the two elders are beamed to a cave by an obelisk and are told by a hologram version of Freyr that the town should prepare for Ragnarok, the end of the world. O'Neill tries to interfere and convince them to take their fate into their own hands, but concedes to Daniel's warnings not to try. Instead, all but Teal'c go back to the church and the cave, where Carter finds a board to switch the hologram into a "phone" (O'Neill's term) to "call" Freyr.

SG-1 contact Freyr, but apparently he cannot help because the planet is protected by a treaty which protects many planets from Goa'uld invasion, including Earth. Also, the decision isn't entirely Freyr's, so he suggests O'Neill step onto the hologram platform to face the Asgard High Council. The meeting does not go well: Interfering with the sun would be interfering with the natural development of the planet, and be a violation of subsection 42 of the "Protected Planets Treaty".

Carter comes up with a plan to bring an artificial element much heavier than plutonium to bond with the plutonium into the sun to restore the natural nuclear processes within the star. The inhabitants of the planet, meanwhile, refuse any assistance, saying that if the gods wish them to die, they accept their fate. Hammond is convinced to bring a rocket ready for launch (mentioning the high price of rockets) to K'Tau. A friend of Carter's, Professor MacLaren, provides the kind of element they need, HU-2340; he is flattered when Carter names the element "Maclarium". Village elder Malchus convinces two suicide attackers to blow up the rocket, killing two members of SG-6. O'Neill is furious about the ignorance, arrogance and hypocrisy of Malchus, and orders his people to leave K'tau to its fate. It takes Daniel and Carter to convince him otherwise. When Daniel still can't get the village to listen, O'Neill rushes into the argument, claiming the Asgard are not gods, but aliens with spaceships.

The K'tau people don't believe him. Carter thinks that if she shuts down the gate at a precise time, a wormhole could still deliver the element into the sun. It doesn't seem to work, but when Daniel joins in a prayer to say sorry and goodbye and that they may still evacuate, suddenly the light shifts to normal.

Carter suspects it might have been the Asgard, now able to shift the sun back without the Goa'uld knowing, being able to claim it was just a success of Carter's wormhole plan. Daniel ends the episode, saying "We'll never really know for sure, will we?"

Notable Quotes
O'Neill: Carter, what just happened?

Elrad: The Eye of Odin grows dim.

Carter: Some sort of shift in the light frequency.

O'Neill: Good. I thought I was having a stroke.

After the sun regains its original colour

O'Neill: Carter, am I having a stroke?