Shaikh Mohammad Razaullah Ansari (8 April 1932 – 25 February 2023) was a distinguished Indian historian of science, physicist, and astronomer. After earning his B.Sc. and M.Sc. in Physics from Delhi University in the 1950s, he pursued a D.Sc. in Mathematical Physics at Eberhard Karl University in Tübingen, Germany, supported by a prestigious Humboldt Fellowship. In 1969, he joined Aligarh Muslim University, where he founded an astrophysics research group, earning international recognition as a Fellow of the Royal Astronomical Society (1972) and a member of the International Astronomical Union (1973). His later passion turned to the history of astronomy, leading him to become the first Indian/Asian President of the IAU's Commission 41 (History of Astronomy) from 1994 to 1997, during which he organized a notable symposium on Oriental astronomy in Kyoto. After retiring in 1994, he dedicated himself to researching medieval Indian and Islamic scientific history, leaving behind a substantial body of published work before his death at age 90.