Altair VII

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Altair VII is the seventh planet in orbit of Altair, in the Altaire Starzone of the Galactic Empire. It was the site of the Imperial Labor Camp that Arle Heinessen was sent to, and from which he later escaped after the construction of the Exodus Fleet.

While lacking in water, Altair VII was rich in other resources, like molybdenum (which was mined by the colonists) and dry ice. (Legend of Galactic Heroes Volume 1: Dawn)