The invisible plane, flying in the direction of the uranium mines. Uranium is a type of chemical element. The Pluto uranium mines were mines that were used for mining uranium. References ↑ As seen in the Super Friends Season 1 episode The Ultra Beam (1973). ↑ As seen in The Ultra Beam. External Links Uranium at Wikipedia Retrieved from "https://superfriends.fandom.com/wiki/Uranium?oldid=48189" Categories: Elements Community content is available under CC-BY-SA unless otherwise noted.