Physicist and Human Rights Activist.
Andrei Dmitrievich Sakharov (May 21, 1921 – December 14, 1989) was a Soviet nuclear physicist, dissident and human rights activist. He gained renown as the designer of the Soviet Union's Third Idea, a codename for Soviet development of thermonuclear weapons. Sakharov was an advocate of civil liberties and civil reforms in the Soviet Union. He was awarded the Nobel Peace Prize in 1975. The Sakharov Prize, which is awarded annually by the European Parliament for people and organizations dedicated to human rights and freedoms, is named in his honor.
Sources:
1.) The World of Andrei Sakharov: A Russian Physicist's Path to Freedom. Oxford University Press. 2005. p. 356. ISBN 9780195156201. "Apparently Sakharov did not need to delve any deeper into it for a long time, remaining a totally nonmilitant atheist with an open heart."
2.) Todd K. Shackelford, Viviana A. Weekes-Shackelford, ed. (2012). The Oxford Handbook of Evolutionary Perspectives on Violence, Homicide, and War. Oxford University Press. p. 465. ISBN 9780199738403. "The Soviet dissident most responsible for defeating communism, Andrei Sakharov, was an atheist."