‘In the early days of rocket science, no one knew what the effects of weightlessness would be,’ writes Space.com. So rocket scientists launched animals— mainly dogs by Russia and monkeys and chimps by the United States— up into space to test the effects of space on living beings and determine whether humans could survive a trip to and from space.
However, NASA clarifies it only sends animals into space when ‘absolutely necessary,’ preferring instead to conduct experiments via computer modeling and the like.
