20 Facts About the Animals We’ve Sent Into Space

The first animals deliberately launched into space and recovered alive were fruit flies, sent aboard a V-2 rocket in 1947. They were small, easy to study, and useful for assessing the effects of high-altitude radiation on living tissue.

In 1949, a rhesus monkey named Albert II became the first primate to go into space. His flight took him about 133 kilometers above Earth, but the capsule’s parachute failed during recovery. The mission yielded valuable biological data, even though Albert II did not survive.

The Soviet space program used dogs in part because researchers believed they were calmer than monkeys in confined spaces. Female dogs were often preferred because their anatomy was better suited to the tight quarters required in a space capsule.

In 1951, the Soviet dogs Dezik and Tsygan became the first canine space pioneers by completing a suborbital flight from which they returned alive. Their mission made it possible to test recovery systems, animal-specific cabins, and the fundamental effects of short-duration spaceflight on large mammals.

Laika, a stray dog from Moscow, became the first animal to orbit the Earth in 1957. Her mission was not designed to allow her to return home, and later reports revealed that she had died after only a few hours in orbit. Her story remains one of the most famous and poignant chapters in the history of spaceflight involving animals.

Laika’s flight demonstrated that a living being could survive launch and reach orbit, but it also highlighted the heavy toll taken during the early space tests. The public’s perception of her fate has evolved over time, as more precise details have come to light. Her mission is still regarded today as both a scientific milestone and a tragedy.

In 1958, a squirrel monkey named Gordo was launched aboard a Jupiter rocket and reached an altitude of approximately 965 kilometers. His capsule was lost after splashdown due to a failure of the flotation system. Despite this, measurements of his breathing and heart rate suggested that a human could survive a similar flight.

In 1959, Able, a rhesus monkey, and Baker, a squirrel monkey, were the first American animals to travel into space and return safely. Able died a few days later during a medical procedure, while Baker lived until 1984. Their successful return made them the first space celebrities.

Some of the early missions involving mice ran into problems even before takeoff. In one instance, the mice chewed through materials inside their cages and died before launch. In another instance, a humidity alert was triggered by a sensor placed under a mouse’s cage, which mistook urine for condensation inside the capsule.

In 1960, the Soviet dogs Belka and Strelka became the first animals to orbit the Earth and return alive. They were not alone on board, however. Their spacecraft also carried smaller animals, insects, plants, and other biological samples, making this mission a major step toward manned orbital flight.

After returning from space, Strelka gave birth. One of her puppies, named Pushinka, was given to President John F. Kennedy’s family. It was one of the most unusual episodes of the Cold War: a puppy sired by a Soviet space dog living in the White House.

Ham, the chimpanzee, flew on a spacecraft in 1961 and was trained to respond to signals by operating levers. His mission demonstrated that not only could primates survive the journey, but they were also capable of performing tasks despite the stress of spaceflight. 

Later in 1961, Enos became the first chimpanzee to orbit the Earth. His flight was originally scheduled to include three orbits, but it ended after two orbits due to technical problems. He returned in good health, paving the way for a manned orbital mission in the years that followed.

In 1963, a French cat named Félicette became the first cat to travel into space and return safely. She took part in a suborbital mission, was recovered unharmed, and provided neurological data from the flight. A second feline mission followed a few days later, but unfortunately, the second kitten did not survive. 

In 1966, the Soviet dogs Veterok and Ugolyok spent 21 days in space. Their mission was to study the effects of long-duration spaceflight and radiation exposure on living organisms. Their time in orbit remains, to this day, the longest spaceflight ever undertaken by dogs.

In 1968, two steppe tortoises orbited the Moon aboard a Soviet spacecraft before returning to Earth. They made this journey before any human being, making them among the least well-known lunar travelers in history.

As space research matured, missions involving animals shifted their focus away from spectacular “firsts” and toward specific biological questions. Subsequent experiments involved insects, fish, frogs, fungi, quail eggs, newts, seeds, cells, and other small organisms. The focus then shifted to development, homeostasis, radiation, reproduction, and long-term survival.

The last manned mission to the Moon also carried five pocket mice as part of an experiment on cosmic rays. Researchers wanted to determine whether the high-energy particles present in space could cause visible damage to the brain or eye tissue. These mice were small, seemingly forgotten passengers aboard one of the greatest missions in history.

In 1973, two spiders named Anita and Arabella were sent into space to see if they could spin webs in zero gravity. They had a hard time at first, but they eventually managed to spin webs in microgravity.

In 2007, tiny tardigrades, also known as “water bears,” were exposed to the hostile environment of space. Some survived the vacuum, dehydration, and cosmic radiation during the experiment. Their resilience pushed the boundaries of survival beyond the confines of spacecraft cabins and into the extreme conditions of space itself.