Though far less famous than later non-human astronauts, the first animals in space were a group of fruit flies, launched to an altitude of 42 miles at the tip of a Nazi-designed V-2 rocket by American military scientists on February 20, 1947. The flies, members of the often-studied species Drosophila melanogaster, made their journey alongside packets of rye and cotton seeds as part of an experiment to study the effects of cosmic rays on living organisms. The flies’ container parachuted to the ground and the insects were retrieved in perfect health.

The first vertebrates sent into space were a series of ill-fated monkeys and mice launched between 1948 and 1951 by American researchers. On June 14, 1949, a Rhesus monkey named Albert II blasted to an altitude of 83 miles in a V-2, surviving the flight but dying on impact. A year later, the U.S. launched a mouse and photographed its behavior in a weightless state, although it too was not recovered alive.

The Soviet Union had better luck, launching (to 62 miles) and recovering a pair of dogs, Tsygan and Dezik, on July 22, 1951. Two months later, the U.S. launched and retrieved an anesthetized monkey named Yorick along with 11 mice. Alas, poor Yorick died after his capsule overheated in the New Mexico sun while awaiting recovery, though nine of the mice survived. Six years later the Soviet Sputnik II probe carried the first animal into orbit, a former stray dog named Kudryavka (“curly”) but later known to the world as Laika (“barker”). She died in her orbiting capsule—no provisions had been made to return her to earth alive—sparking debate in the West over the ethics of sacrificing animals to advance science. In 1960, the Soviet’ Sputnik 5, carrying two dogs as part of its animal-laden cargo, was successfully recovered after orbit. The following year, despite Cold War tensions, Soviet Premier Nikita Khrushchev gave the puppy of one of Sputnik 5’s dogs to young Caroline Kennedy. Pushinka, as she was known, eventually gave birth to four puppies of her own, which President John F. Kennedy referred to as the “pupniks.”