Laika (from Russian: Лайка, a breed of dog, literally: "Barker") was a Russian space dog who became the first living creature from Earth to enter orbit. At one time a stray wandering the streets of Moscow, she was selected from an animal shelter. Originally named Kudryavka (Russian: кудрявка), she was renamed Laika after her breed type. After undergoing training with two other dogs, she was selected to be the occupant of the Soviet spacecraft Sputnik 2 and was launched into space on 3 November 1957.
Laika died a few hours after launch from stress and overheating, probably due to a malfunction in the thermal control system. The true cause of her death was not made public until decades after the flight.
Although Laika did not survive the trip, the experiment proved that a living passenger could survive being launched into orbit and endure weightlessness. It paved the way for human spaceflight and provided scientists with some of the first data on how living organisms react to spaceflight environments.