From Fruit Flies to Tardigrades: Animals That Paved the Way for Human Spaceflight

For almost eight decades, a variety of creatures acted as the first explorers of space, allowing researchers to assess radiation, microgravity and other hazards. Early tests featured fruit flies launched on a V-2 rocket in 1947, followed by the first mammal, rhesus monkey Albert II, in 1949. The Soviet program introduced dogs such as Tsygan, Dezik, and the iconic Laika, while the United States sent monkeys like Gordo, Able and Baker, with mixed survival outcomes.

Successful orbital flights came with Soviet dogs Belka and Strelka in 1960 and later with French cat Félicette in 1963. The 1960s also saw chimpanzees Ham and Enos demonstrating task performance in orbit. In the late 1960s, Soviet tortoises on Zond 5 completed a lunar loop, and subsequent missions carried mice, spiders, and, in 2007, tardigrades that endured vacuum exposure. Today, animal research continues aboard the International Space Station, focusing on bone loss and muscle atrophy, cementing these “unsung heroes” as essential contributors to modern space travel.