Viktor Amazaspovich Ambartsumian (Russian: Виктор Амазаспович Амбарцумян; Armenian: Վիկտոր Համազասպի Համբարձումյան, Viktor Hamazaspi Hambardzumyan; 18 September [O.S. 5 September] 1908 – 12 August 1996) was a Soviet Armenian astrophysicist and science administrator. One of the 20th century’s top astronomers, he is widely regarded as the founder of theoretical astrophysics in the Soviet Union. – Wikipedia