Space Research
Chimpanzee, name unnown, strapped for “training”

Nonhuman animals have been used to determine the “impacts of spaceflight upon the human body.”[1] “Initially, animals were used as surrogates to test the suitability of the space environment for human habitation. Once it was determined that complex biological organisms could live in space, humans ventured into space, and took animals along as experimental subjects.”[2] This practice continues today.

Starting in the U.S. in 1935, animals were first used in “in ground-based altitude and acceleration experiments.” These studies lead to the “the first sub-orbital rocket-powered animal flight” in 1948 involving a rhesus macaque named Albert. Afterward, several more flights occurred with nonhuman primates and mice; however, it wasn’t until 1951-52 that the animals on board survived the flight and were “successfully recovered,” deeming them “the first living creatures to survive the test program.”[3] In prior experiments, animals died from dehydration or starvation during the flight, in explosions on board the shuttle, when plummeting into the water after reentry, or were simply “lost at sea.” In the early 1950s, the U.S Air Force captured 65 young and infant chimpanzees from Africa and established an aeronautical research facility at the Holloman Air Force Base in Alamogordo, NM. Until the mid 1960s, the Air Force used these chimpanzees to test the forces of gravity, the effects of high-speed movement, and other conditions anticipated in space travel.

During this same time, the Soviet Union began sending “mice, rats and rabbits as one-way passengers for their initial tests.”[4] Later, dogs became the preferred species choice for their space research, and in 1957 the Soviet Union launched Sputnik II into orbit, carrying a dog, named Laika. This lead to the “space race” between the U.S. and the Soviet Union, in which “American and Russian scientists utilized animals—mainly monkeys, chimps and dogs—in order to test each country's ability to launch a living organism into space and bring it back alive and unharmed.”[5] In 1958, the U.S. accelerated its space program and began consuming increasing numbers of nonhuman animals for aerospace research. Mice, guinea pigs, and several species of monkeys were used in experiments, and as time went on, chimpanzees became preferred “test subjects” for space flight research. Eventually, rats, mice, and monkeys replaced chimpanzees and have become the standard species for aerospace research.

Today, animals continue to be used in space research to determine the “risks associated with long-term human exposure to spaceflight, especially microgravity.” Specific areas of interest involving an animal’s response to spaceflight include “bone, muscle, immunology and microbiology, neuroscience including behavior and performance, nutrition and metabolism and the cardiovascular system.”[6] Besides rodents and nonhuman primates, snails, spiders, fish, turtles, amphibians, and baby mammals are sent into space, although “baby mammals have a hard time in space because they normally huddle for warmth—and in space, it's hard to huddle when bodies drift and float. It's also difficult for babies to nurse when they can't locate their mother's nipple.”[7]

Common areas of aerospace research and the animals typically used 

  • musculoskeletal (rats)
  • sensory motor and neuroscience (rats, rhesus monkeys)
  • immunology and disease (rats, rhesus monkeys, mice)
  • wound healing in injuries, burns, cuts, fractures, and contusions (rats)
  • cardiovascular (rats, pigs)
Chimpanzee, name unknown, slammed at high speed

Typical space experiments on animals include “bone fracture studies, radiation exposure, and partial gravity/hypergravity studies.” During the multi-million dollar Bion flights project, NASA researchers were able “to provoke and study the development of and recovery from radiation sickness in rats.”[8] In anti-gravity studies for muscle atrophy and bone loss, researchers subject rats to a procedure called hindlimb unloading, where researchers suspended the rats upside down from their hind limbs through tail traction, with the weight remaining in their forelimbs, head, and upper back. Rats may stay like this for weeks at a time; postmortem indicators for stress have been observed through weight loss, atrophy of the thymus, adrenal hypertrophy, and increased corticosterone levels.[9] For studies on microgravity in space, mice are securely sealed in “lockers” that contain food and water. On the shuttle, the crew is able to observe the mice, but do not have access to them. As a result, many mice have died from starvation or other problems during the flight.

On July 8, 2011, NASA launched its final space shuttle, “ending a program that sent five shuttles on 134 missions to space…and, as usual, it will carry an astonishing array of organisms and equipment all in the name of scientific discovery.”[10] Among the organisms on board are mice from the Pennsylvania State University. The mice “will spend almost two weeks on the shuttle, and when they return, researchers will compare their bone density to control mice that never left Earth. The team hopes to better understand the effects of weightlessness on the ability of bone marrow stem cells to build bone, and the mechanism of bone loss that result from prolonged bed-rest and aging.”[11]


Despite the significant advances that have been made over the years in both technology and human medicine, a 2004 report sponsored by NASA concluded that animal research is still “an integral tool for understanding and ameliorating the known and yet-to-be-discovered impacts of spaceflight upon the human body”[12] and a high-priority requirement for all areas of research.

No efforts have really been made to decrease the use of animal models, to create alternatives to animal use, or to focus more on human-based research, even though less invasive (and more relevant) studies have already taken place with humans. Yet, even with animal and human research data already available, animals continue to be subjected to repetitive research involving stressful and painful procedures. As with musculoskeletal research, “Since the 1970’s it has been known that human muscle changes during even short stays in the microgravity environment. This clinical observation in humans is replicated in experimental models in flight, such as rats and in ground analogues such as hindlimb suspension (rat) and human bed rest studies.”[13] In the end, if human-based research can, and in many instances already has, provided people with information on the effects of space travel on the human body, then the continued funding of repetitive and unnecessary animal research with taxpayer dollars hurts not only the animals, but us as well.

[2] Borkowski, G.,  Wilfinger, W., &  Lane, P. (1995/1996, Winter). Laboratory Animals in SpaceAnimal Welfare Information Center Newsletter, 6(2-4).

[3] Ibid.

[4] National Aeronautics and Space Administration.(n.d.). A Brief History of Animals in Space.

[5] Ibid.

[7] National Aeronautics and Space Administration. (n.d.). Animals in Space.

[9] Morey-Holton, E., & Globus, R. (2002, April). Hindlimb unloading rodent model: technical aspects. Journal of Applied Physiology, 92(4), 1367-1377.

[10] Johnson, J. (2011, July 8). Science in Space. The Scientist.

[11] Ibid.