Oleg Gazenko, one of the lead scientists in the Soviet space program, later said this mission was one of his big regrets:
"The more time passes, the more I'm sorry about it. We shouldn't have done it. We did not learn enough from this mission to justify the death of the dog."
68 years ago today, Laika the dog was launched into space by the Soviet Union to become the first animal to orbit the Earth.
No plans were made for her return and she died a few hours later due to overheating and stress.