Janus' outpost was a planet in the Milky Way galaxy which has a Stargate. Ten thousand years ago, the Ancient scientist Janus had an outpost on the planet where he also stored his his time travel technology. In the future, the Tau'ri found the outpost and also discovered Janus' technology. They locked the planet's Stargate so that Stargate Command in the current timeline would not come to the planet. (SG1: "Relativity")
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