Cosmic Girls (Hangul: 우주소녀; RR: Uju Sonyeo; Chinese: 宇宙少女; pinyin: Yǔzhòushàonǚ), also known as WJSN, is a South Korean-Chinese girl group formed by Starship Entertainment and Yuehua Entertainment which debuted in 2016. Their first extended play Would You Like? was released on February 25, 2016. Starting in December 2015, Starship Entertainment began releasing information about the band members in their four units. On December 21, Cosmic Girls released a Christmas cover of "All I Want For Christmas Is You" by Mariah Carey. Cosmic Girls debuted on February 25, 2016 with the release of their debut mini album Would You Like?, including the title tracks "Mo Mo Mo" and "Catch Me".The group held their debut stage on the February 25th episode of M Countdown with "Catch Me" and "Mo Mo Mo".

On July 11, Starship Entertainment confirmed that I.O.I's Yoo Yeon-jung would be joining the group. In August 2016, SeolA, Exy, Soobin, Eunseo, Cheng Xiao, Yeoreum, and Dayoung teamed up with label mate Monsta X to form the unit "Y-Teen." Y-teen is a project unit group that will be promoting as CF models for KT’s phone fare service, and will release EPs, music videos, and various entertainment content. On August 17, Cosmic Girls released their second mini-album The Secret with all 13 members. On January 4, 2017, Cosmic Girls released their third extended play From. WJSN. On June 7, Cosmic Girls released their first full length studio album Happy Moment. - Wikipedia