Is it morally defensible to experiment on animals in space ? If so, what considerations should be made?

Animal testing, whether conducted in space or on Earth, remains ethically questionable.

Most scientists claim that animal-testing is necessary. However, studies have shown that it does not reliably predict results in human beings. This is explained by the fact that animals’ physiology can be very different from humans’. In addition, an alternative testing method is currently being developed. It is called organs-on-chips, and consists in human cells grown on lab glasses, which imitate human physiology and allow us to study how the drug will be metabolized, absorbed, induce physiologic effects or an immune response, and finally how it will be excreted.

Even so, organs-on-chips cannot be connected to reproduce a whole body system, which is needed for NASA experiments. Consequently, pending a less debatable research subject, scientists working for space conquest need animals to help them understand what could possibly happen to humans if we get to live in space. Because of their shorter life cycles,  they are the perfect subjects for teratology, drug toxicity,  or embryology in space.

To ensure reliable results, we need the animals to feel comfortable. It is therefore our best interest to care for them, and to make sure that no animal is abused. The minimal number of subjects should be used, and replaced by other techniques when possible.

These bioethical principles need to be acknowledged/endorsed by every country preparing space missions.