What is Sputnik 2?

Sputnik 2 was the second artificial satellite launched by the Soviet Union on November 3, 1957, following the historic Sputnik 1. It was significant for carrying the first living creature into orbit, a dog named Laika, which provided valuable data on the effects of space travel on biological organisms. Sputnik 2 was larger than its predecessor and included scientific instruments to study cosmic radiation and the Earth's atmosphere. The mission lasted about 162 days before re-entering Earth's atmosphere in April 1958.