Edward Elliot explains how Sputnik helped to launch a technological revolution.
The Soviet's Sputnik program consisted of four satellites, three of which reached an Earth orbit. Sputnik 1, launched on Oct. 4, 1957, became the first artificial satellite to successfully orbit the Earth. It was a metallic sphere about 2 feet across, weighing 184 pounds, with long "whiskers" pointing to one side, and stayed in orbit for six months before falling back to Earth. Its rocket booster, weighing 4 tons, also reached orbit and was easily visible from the ground.