Sven "Buttercup" Hansen was a Human prize fighter who lived during the 22nd century. He was an ancestor of Magnus Hansen, Irene Hansen and Seven of Nine. (VOY episode: "11:59") The captain of the ECS Bjarni Herjolfsson was a great fan of Hansen and, consequently, named Hansen's Planet after him when his ship discovered it at some point prior to 2163. (ENT - Rise of the Federation novel: A Choice of Futures)