The first manmade satellite is known as Sputnik 1. Launched by the Soviet Union on October 4, 1957, it marked the beginning of the space age and the space race between the United States and the USSR. Sputnik 1 transmitted radio pulses that could be received on Earth, providing valuable data and demonstrating the feasibility of human-made objects orbiting the planet. The satellite orbited the Earth for about three months before its batteries depleted, but it continued to orbit for years until it re-entered the atmosphere in 1975. Sputnik 1 remains a significant milestone in human exploration of space.