Aldan-3 is a planet in the Milky Way galaxy. Vala visited Aldan-3 in order to retrieve a data disk from Arvold's home. There she was attacked by Arvold and Grag, but managed to escape. The planet is very similar to Earth, in the fact that the houses of those who reside there are very similar to Earth's population's homes. (SG1: "Vala Mal Doran 1")