The First Dog in Space Did Not Survive the Mission

On November 3, 1957, less than a month after Sputnik 1 opened the Space Age, the Soviet Union launched Sputnik 2 carrying a small stray dog named Laika — the first animal ever to orbit the Earth. Her capsule had no system to bring her back. Re-entry technology simply did not exist yet, and the flight was rushed to mark the 40th anniversary of the October Revolution.

Engineers built the cabin for a short ordeal, not a survivable journey. The life-support and cooling systems failed early, and cabin temperatures climbed past 90 degrees. Laika is now believed to have died of overheating within hours of reaching orbit, not after several days as Soviet officials first claimed.

Her one-way flight proved a living creature could endure launch and weightlessness — the data that made human spaceflight thinkable.

For decades the true cause of her death stayed hidden. One of her trainers, Oleg Gazenko, later expressed regret, and Laika became a lasting symbol in debates over animal welfare in research.