Atropos was a planet in the Milky Way galaxy, which held a Stargate. The Goa'uld empire enslaved the race of the planet and addicted them to a drug known as roshna, which kept them subjugated. (SG1: "Siren Song")
The Planet was prievouslly under control of the Goa'uld Sobek, who was overthrown during SG-1's visit to the planet in 2007. The planet is now under the control of the Ilempiri people.