Today we remember two heroes whose bravery transcended the political rivalries of their time in service of all mankind. On July 22, 1951, Soviet pooches Dezik and Tsygan (“Gypsy”) became the first dogs to make a sub-orbital flight.

The European Society of Dog and Animal Welfare has a primer on the U.S.S.R.’s history of using dogs to test space exploration, launching some 57 pups in the service of science. They weren’t the first Earthlings, having been beaten by fruit flies in 1947, a monkey in 1949, and a mouse in 1950, but they were the first dogs. The Russians preferred strays, unaccustomed to the comforts of a home, and females exclusively, because of the way the suits were designed to collect urine.

Dezik and Tsygan were the first, both returning to Earth unharmed after reaching a maximum altitude of 110 kilometers. Tsygan was adopted by Soviet physicist Anatoli Blagonravov. Her companion adventurer, Dezik, was launched into another sub-orbital flight with a new partner dog, Lisa, in September of that year. Both dogs died on the journey. Godspeed, four-legged pioneers.