Ary Abramovich Sternfeld

Ary Sternfeld (14 May 1905 – 5 July 1980) was co-creator of the modern aerospace science. He was a Polish engineer of Jewish origin, who studied in Poland and France. From 1935 until his death he worked in Moscow.

He was the first person to describe the bi-elliptic transfer technique of changing orbits, in 1934.

In 1934, Sternfeld won the Prix REP-Hirsch (later known as the Prix d'Astronautique) of the French Astronomical Society for his book Initiation à la Cosmonautique. He is thus credited with introducing the word cosmonautics in the language of science and engineering.