The name of the first satellite that humans put into space is Sputnik 1. It was launched by the Soviet Union on October 4, 1957. Sputnik 1 was a small, spherical satellite that weighed about 83.6 kilograms (184.3 pounds) and had a diameter of 58 centimeters (23 inches). It was equipped with two radio transmitters that sent out a "beep-beep" signal that could be heard by radio receivers around the world. Sputnik 1 orbited the Earth for three months before it re-entered the atmosphere and burned up.