P9Q-281 was among the planets entered into the computer by O'Neill when he was carrying the knowledge of the Ancients from the Ancient repository. A pedestal near the stargate was inscribed with symbols matching the language of the Ancients. Believing it may hold the key to help O'Neill, SG-1 was joined by Major Castleman on the mission to the planet. However, they found no indigenous life, and two suns which caused temperatures to rise above 200F during the day. When the DHD seized up, the team relied on schematics drawn by O'Neill from the Ancient knowledge database, enabling them to repair the DHD and return home.

Cross Reference: Ancients, Ancient Repository

Episode Reference: The Fifth Race