Father Ferdinand Verbiest (9 October 1623 – 28 January 1688) was a Flemish Jesuit missionary in China during the Qing dynasty. He was born in Pittem near Tielt in the County of Flanders (now part of Belgium). He is known as Nan Huairen () in Chinese. He was an accomplished mathematician and astronomer and proved to the court of the Kangxi Emperor that European astronomy was more accurate than Chinese astronomy. He then corrected the Chinese calendar and was later asked to rebuild and re-equip the Beijing Ancient Observatory, being given the role of Head of the Mathematical Board and Director of the Observatory.