16th-century Chinese astronomers

Xu Guangqi or Hsü Kuang-ch'i (April 24, 1562– November 8, 1633), also known by his baptismal name Paul, was a Chinese agronomist, astronomer, mathematician, politician, and writer during the Ming dynasty. Xu was a colleague and collaborator of the Italian Jesuits Matteo Ricci and Sabatino de Ursis and assisted their translation of several classic Western texts into Chinese, including part of Euclid's Elements. He was also the author of the Nong Zheng Quan Shu, a treatise on agriculture. He was one of the "Three Pillars of Chinese Catholicism"; the Roman Catholic Church considers him a Servant of God. On April 15, 2011, Vatican spokesman Federico Lombardi announced the beatification of Xu Guangqi.

Zhu Zaiyu (Chinese: 朱載堉; 1536 – 19 May 1611) was a Chinese mathematician, physicist, choreographer, and music theorist. He was a prince of the Chinese Ming dynasty. In 1584, Prince Zhu innovatively described the equal temperament via accurate mathematical calculation.