Sputnik

Sputnik was the first artificial satellite, launched by the Soviet Union on October 4, 1957. It marked the beginning of the space age and sparked the Cold War space race between the U.S. and the USSR. Weighing about 183 pounds, Sputnik orbited the Earth and transmitted radio signals back to the ground, which could be received by radio operators. Its launch demonstrated significant advancements in rocket technology and encouraged global interest in space exploration, leading to further developments in satellite technology, human spaceflight, and eventually, the Apollo moon missions.