A three-stage North Korean expendable liquid-fuelled rocket that possibly derived from a two-stage ballistic missile known as Taepo Dong in the West. After three known unsuccessful launch attempts beginning in 1998, a 30-m-tall 91-tonne Unha-3 rocket successfully delivered the Kwangmyŏngsŏng-3 Unit 2 satellite into a Sun-synchronous orbit in December 2012. Unha had a repeat success in February 2016, launching Kwangmyŏngsŏng-4 into Earth orbit.