A dog sent to die and tortoises that flew around the moon: These are the most famous, bizarre, and important animals that have been sent to space - INSIDER

A dog sent to die and tortoises that flew around the moon: These are the most famous, bizarre, and important animals that have been sent to space  INSIDER

Animals went to space before humans, and NASA says their efforts prevented "great losses of human life." Animals are still sent today for experiments.