The 56th Emperor Jossano was a starship of the Race's Conquest Fleet. It carried a large portion of the Fleet's explosive-metal bombs in an armored chamber in the vessel's heart. In 1942, when the Fleet invaded Earth, the ship landed in the southern Soviet Union, where it was destroyed by German heavy artillery battalion Dora. The armored chamber did not prevent the weapons from being destroyed by secondary explosives. (Fortunately, the weapons themselves did not detonate.) Large chunks of radioactive plutonium were scattered across the landscape. This plutonium was later captured in a raid by the SS and NKVD, and proved invaluable to human research into the making of atomic bombs.