超新星 (Cho Shin Sei) is six member South Korean boyband: 초신성 (Cho Shin Sung) They made their Japanese debut in September of 2009 with three singles. Their first Japanese album 'hana' was released on the 21st of October, 2009. Official Site: www.choshinsei.com Members: Yunhak Stage Name : Spica Yunhak | Yunhak | ユナク (윤학 or 允鶴) Name: Jung Yunhak (정윤학, 鄭允鶴) Birthdate: December 2, 1984 (1984-12-02) (age 26) Position: Leader, Vocalist