Jang Young­sil, The Greatest Scientist in Joseon

Jang Young Sil 장영실 蔣英實 (alt spellings: Jang Yeong-Sil) Born: 1390 (Speculative) Died: sometime after 1442 (exact date unknown) As Seen On TV:  100 years before Nicolaus Copernicus, lived one of the WORLD’s greatest scientist and astronomers, Jang Continue Reading →