Laika didn't die peacefully after days in orbit — the truth took 45 years

In 1957 the Soviet Union launched the stray dog Laika aboard Sputnik 2, the first animal to orbit Earth. Officials claimed she survived for days and died painlessly. Not until 2002 did a mission scientist reveal she had actually died within 5-7 hours, from overheating and stress after the capsule's cooling system failed.

— Dimitri Malashenkov (Institute of Biomedical Problems, Moscow), Historical record — Disclosed at the World Space Congress, Houston, October 2002