Sent on the Sputnik 2, Laika was the first living creature [a dog] to orbit the Earth. Since there was no technology to de-orbit, she died in space as intended. She died from overheating. Her reports weren’t made public until 2002 so up until then everyone was told that she was euthanised prior to oxygen depletion (the six-day mark). Laika has been the topic of ethics and animal cruelty in science for many years. Laika paved the way for human space-flight.