For nearly 80 years, fruit flies, dogs, monkeys and even tortoises have served as humanity’s test pilots in the void beyond Earth.
The cosmic menagerie began in 1947, when America launched fruit flies aboard a V-2 rocket to an altitude of 68 miles. Scientists wanted to study radiation effects on living tissue. Every fly survived the parachute ride home, making them the first animals to complete a space mission and live.
Two years later, Albert II, a rhesus monkey, claimed a darker milestone. He became the first mammal to reach space but died when his parachute failed on descent. The hazard would plague early missions for more than a decade.
The Soviet Union answered with canines. Tsygan and Dezik reached space and returned safely in 1951, becoming the first dogs to survive the round trip. Their success made them instant celebrities in Moscow.
Then came Laika. The stray dog plucked from Moscow streets became the first animal to orbit Earth aboard Sputnik 2 in 1957. The technology to bring her back did not exist. She died within hours, alone in her capsule, and her sacrifice galvanized global attention on the cost of space exploration.
America’s response came in 1958 with Gordo, a squirrel monkey who endured launch, weightlessness and reentry only to perish when his parachute failed. His capsule sank into the Atlantic, unrecovered.
Breakthrough arrived the following year. Miss Able and Miss Baker became the first monkeys to survive spaceflight intact. Able died four days later from complications, but Baker thrived. She lived until 1984, drawing crowds at Alabama’s US Space and Rocket Center, where visitors still leave bananas at her grave.
The Soviet program scored its own recovery triumph in 1960. Dogs Belka and Strelka orbited Earth and returned safely, proving that living creatures could withstand extended weightlessness. Strelka later had puppies, and Soviet leader Nikita Khrushchev gave one, Pushinka, to President John F. Kennedy’s daughter Caroline as a Cold War diplomatic gift.
Ham the chimpanzee rewrote the mission playbook in 1961. Trained to pull levers during flight, he proved that a passenger could think and perform tasks while weightless. His success helped clear the way for Alan Shepard to become the first American in space months later. That same year, Enos became the first and only chimp to orbit Earth.
France entered the space race in 1963 with Félicette, a black-and-white Paris street cat who became the first and only feline astronaut. She survived her mission but was euthanized two months later so scientists could study her brain.
The lunar era brought stranger travelers. In 1968, two Soviet tortoises aboard Zond 5 became the first Earth creatures to circle the Moon and return alive. Apollo 17 carried five mice — Fee, Fi, Fo, Fum and Phooey — around the Moon in 1972. The following year, spiders Arabella and Anita aboard Skylab demonstrated that webs could be spun in weightlessness.
The ultimate survivors emerged in 2007. Microscopic tardigrades, nicknamed “water bears,” endured direct exposure to the vacuum of space, reviving afterward as if nothing had happened.
Today’s animal astronauts live at the International Space Station, housed in specialized drawer-like habitats. Rats, mice, insects and sea creatures help researchers study bone loss and muscle wasting in weightlessness. They are tracked by numbers, barcodes or experimental groups rather than personal names.
NASA calls these pioneering creatures the “unsung heroes of animal astronauts.”
