Student Features

Animals in Space
05.06.04
A fish swimming in microgravity
Can fish swim in microgravity? Do bees make honey in space? Can ant farms exist on the Space Station? These are just a few of the questions scientists hope to answer by taking animals into space.

Image to right: The best way to learn how fish swim in microgravity is to take them into space and watch what happens
Credit: NASA


Scientists want to know how the body reacts to microgravity. Many experiments can be conducted on humans while they work aboard the Space Shuttle or International Space Station (ISS), but many others interfere with daily activities; that's where the animals come into play. And while scientists may not really care how a rat reacts to space conditions, animal data can transfer to human models and help prevent or solve physical issues people face today.

Animals go into space to help conduct scientific research only when absolutely necessary. Researchers prefer to research with computer models, or by involving the astronauts directly. For some experiments, however, only animals will work. Sometimes the situations need to be closely controlled-such as a monitored diet. Human astronauts generally aren't willing to agree to eat the same amount and type of food, so this experiment would be a burden to them. Animals, however, always have monitored feedings.

A chimpanzee being held by a researcher
Image to left: Chimpanzees were one of the first mammals to travel into space
Credit: NASA


In the earlier days of space exploration, nobody knew if people could survive a trip away from Earth, so using animals was the best way to find out. In 1948, a rhesus macaque monkey named Albert flew inside a V2 rocket. In 1957, Russians sent a dog named Laika into orbit. Both of these flights showed that humans could survive weightlessness and the effects of high gravitational forces. After several more flights, the number of animals sent into space decreased. Most experiments could be conducted in space without involving animals.

In 1973, however, a Skylab space project studied circadian rhythm. This experiment used several mice. From there, the Space Shuttle program evolved, which included a more suitable environment for animals.

An astronaut treating a frog with care in space
Image to right: Animals are treated with care while they're in space
Credit: NASA


Due to the housing needs and the practicalities of space travel, the lowest form of life is most suitable for space travel. Often, experiment results using snails and fish can be applied to human conditions: inner ear exams can be done in a snail rather than a highly evolved mammal, and genetic studies can be conducted in fish. While there is not a one-to-one transfer, the similarities are enough to gain necessary knowledge.

Taking animals into space requires special considerations. If a group of laboratory mice were to fly aboard the next Space Shuttle mission, what would be needed? Traditional aquarium-style cages don't provide enough traction for mice to walk around; instead, space mice have wire mesh cages so their toes can grip a rougher surface. Wood chips couldn't be used for bedding; they wouldn't stay in place. Gravity-feed water bottles wouldn't work; pressurized water containers are needed instead. Bowls of dry food aren't practical, so compressed food bars are provided instead. As for how to clean the cages, a special waste containment system has been created to keep everything in its place.

Do the animals like living in microgravity? Does floating instead of walking confuse them? "Amazingly, they adapt very quickly," says Laura Lewis, a member of NASA Ames Institutional Animal Care and Use Committee. "Within 5 minutes, mice are floating in their living spaces, grooming themselves, and eating, just as they would on Earth."

"Good science sets up hypotheses for an experiment, but sometimes the result is not what you expect," says Lewis. "While we test our projects on the ground and in simulators, once we get into space, we are sometimes surprised by what we learn."

What are some of the results of animals in orbit? Fish and tadpoles swim in loops, rather than straight lines, because there is no up or down to orient them, Lewis says. If a light shines, the fish use that as their guide source and swim towards the light. 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.

Animals that travel in space are cared for ethically and humanely, Lewis says. "The Institutional Animal Care and Use Community looks at the most humane alternatives for taking animals into space," she says. "Regulations for animal research are more intense than for using people in research because people can give consent. Animals can't object, so people need to work on their behalf. Animal housing rules are more extensive than the requirements for human children day care centers. NASA facilities that house animals for research are accredited by an organization that requires proof that animals are cared for in a facility that meets those standards." The United States Department of Agriculture Animal Welfare Act and the Public Health Services Policy Act protect research animals and set minimum standards.

"Animals don't go into space very often," Lewis says. "There are so few flight opportunities for a mission to include animals, so the project has to be pretty important to earn a spot on any trip into space. When animals do make the trip, their welfare is a key concern."

Published by NASAexplores