Manuel Dias the Younger (1574 – 4 March 1659)^[1] was a Portuguese Jesuit missionary.

Manuel Dias the Younger (Latin: Junior) acquired his epithet to distinguish him from Manuel Dias the Elder (c. 1561–1639).^[2] He is also known as Emanuel or Emmanuel Diaz. His name was sinified as Yang Manuo (陽瑪諾), and he was also referred to by his courtesy name Yanxi (演西).

Dias arrived in China in 1610, reaching Beijing in 1613. He introduced the telescope into China just a few years after it had been developed in the Netherlands (1608). The telescope was first mentioned in his Tian Wen Lüe (Explicatio Sphaerae Coelestis in Latin or Summary of Astronomy in English) in 1615.^[3] In the Tian Wen Lüe he presented the latest European astronomical knowledge in the form of questions and answers. The book was studied and published until the 19th century.

• Wenceslas Pantaleon Kirwitzer

• Saraiva, Luís; Jami, Catherine (2008). The Jesuits, the Padroado and East Asian science (1552-1773). Singapore: World Scientific. ISBN 978-981-277-126-1. OCLC 262555689.
• Liam Matthew Brockey, "Journey to the East: the Jesuit mission to China, 1579–1724", Harvard University Press, 2007, ISBN 0-674-02448-6
• Joseph Needham, "Chinese astronomy and the Jesuit mission: an encounter of cultures", China Society, 1958
• Francisco Rodrigues, "Jesuitas portugueses astrónomos na China, 1583–1805", Tipografia Porto Medico, 1925
• Joseph Needham, Ling Wang, "Science and Civilisation in China", ISBN 978-0-521-05801-8