Catholic clergy scientists

Georges Henri Joseph Édouard Lemaître ( lə-MET-rə; French: [ʒɔʁʒ ləmɛːtʁ] ; 17 July 1894 – 20 June 1966) was a Belgian Catholic priest, theoretical physicist, mathematician, astronomer, and professor of physics at the Catholic University of Louvain. He was the first to theorize that the recession of nearby galaxies can be explained by an expanding universe, which was observationally confirmed soon afterwards by Edwin Hubble. He first derived "Hubble's law", now called the Hubble–Lemaître law by the IAU, and published the first estimation of the Hubble constant in 1927, two years before Hubble's article. Lemaître also proposed the "Big Bang theory" of the origin of the universe, calling it the "hypothesis of the primeval atom", and later calling it "the beginning of the world".

José María Albareda Herrera (Caspe, 15 April 1902 - 26 February 1966, Madrid) was a Spanish soil scientist and science administrator. From its 1939 creation by Francoist Spain to his 1966 death, he was the secretary general and head of the Higher Council of Scientific Research (CSIC), the main Spanish scientific institution.
He was one of the first numerary members of the Opus Dei (from 1937) and was a close friend of its founder, Josemaría Escrivá. He was ordained a priest in 1959. In 1960, he was appointed the first president of the University of Navarra.

Fernando Ocáriz Braña (born 27 October 1944) is a priest of the Catholic Church who has been the prelate of Opus Dei since 2017. Ocáriz is the fourth person to head Opus Dei since its founding in 1928. He is widely published in philosophy and has been a consultor of the Congregation for the Doctrine of the Faith since 1986.

Jean Baptiste Carnoy (11 January 1836 – 6 September 1899), born in Rumillies (Belgium), was a Roman Catholic priest and a scientist in the field of cytology. He made the initial explanation of the real nature of the albuminoid membrane, and conducted noted experiments on cellular segmentation.