Epsilon 119 was a star.
All nuclear fusion in Epsilon 119 had stopped by the 24th century and the star was considered dead. In 2370, Gideon Seyetik and the crews of Deep Space 9 and the USS Prometheus planned to ignite protomatter on Epsilon 119, with the hope that the protomatter cascade effect would transform carbon and oxygen into elemental hydrogen and restart Epsilon 119's nuclear fusion. Seyetik later piloted a shuttlepod carrying the protomatter, killing himself in the crash, but successfully reigniting Epsilon 119. Benjamin Sisko noted that Epsilon 119's rebirth was a fitting tribute to Seyetik and his brilliance. (DS9 episode: "Second Sight")