What were Sputnik 1 and Sputnik 2?

Sputnik 1 and Sputnik 2 were the first two artificial satellites launched by the Soviet Union, marking significant milestones in the space race. Sputnik 1, launched on October 4, 1957, was the first satellite to orbit Earth, transmitting radio signals that could be received on the ground. Sputnik 2 followed on November 3, 1957, and carried the first living creature into space, a dog named Laika. These missions demonstrated the Soviet Union's advancements in space technology and sparked global interest in space exploration.