Sputnik

Sputnik refers to the Soviet Union’s early space program and to the first artificial Earth satellite, launched October 4, 1957, from the Baikonur Cosmodrome. The name, meaning “satellite” or “companion” in Russian, became a symbol of the dawn of the Space Age and the broader Space Race between the Soviet Union and the United States.

Sputnik 1 details: a polished aluminum sphere, 58 cm in diameter, weighing 83.6 kg, it carried a radio transmitter that emitted beep signals on two frequencies (20.005 and 40.002 MHz). It was launched into a low Earth orbit by a modified R-7 Semyorka intercontinental ballistic missile. It completed an orbit roughly every 96 minutes, with a perigee around 215 km and an apogee around 939 km, and its transmissions continued for about three weeks before reentering the atmosphere on January 4, 1958.

Sputnik program and successors: Notably Sputnik 2, launched November 1957, carried the dog Laika, followed by Sputnik 3 in 1958 with a larger suite of scientific instruments. The program catalyzed the Space Age, prompted U.S. policymakers to accelerate their own space efforts, and contributed to the development of international satellite tracking networks and scientific collaboration.

Legacy: Sputnik’s successful deployment demonstrated the feasibility of artificial satellites, helped catalyze advances in physics and engineering, and influenced science education, technology policy, and the course of human space exploration for decades to come.