Sputnik 1 launched into orbit on 4 October 1957, becoming the Soviet Union’s first artificial satellite.
The launch took place from Baikonur Cosmodrome aboard an R-7 rocket. The polished spherical satellite carried four external antennas and transmitted radio beeps that could be tracked by receivers around the world. Its launch marked the beginning of the Space Age and intensified the Space Race between the Soviet Union and the United States.
Sputnik 1 did not carry people or scientific instruments as complex as those on later spacecraft. Its main technical achievement was demonstrating that a satellite could be placed into orbit and transmit signals from space. It reentered Earth’s atmosphere on 4 January 1958 after roughly three months in orbit.
A common mix-up is confusing Sputnik 1 with Sputnik 2, which launched the dog Laika less than a month later.