Ancient China had seen little Western contact before the 16th century CE, the language, culture and science all being allowed to develop independently of foreign influence. By the time European Jesuit missionaries arrived in the 16th century CE, Chinese science and astronomy were behind in terms of European technological advancement. The Jesuits eventually held important positions at Chinese institutions and introduced new texts, astronomical tables, a new calendar and several new scientific instruments. There is also, however, some debate as to the extent of the Jesuit scholars' influence and the limitations of their own knowledge placed on the development of science in China.
This is a companion discussion topic for the original content at https://www.worldhistory.org/article/1582/jesuit-influence-on-post-medieval-chinese-astronom/.