Szputnyik1

Szputnyik1, also known as Sputnik 1, was the first artificial satellite launched into orbit. Developed by the Soviet Union under the direction of Sergei Korolev, it marked the beginning of the Space Age and the Space Race. The launch occurred on 4 October 1957 from Baikonur Cosmodrome in the Kazakh Soviet Socialist Republic (now Kazakhstan) using an R-7 Semyorka rocket. The mission demonstrated the feasibility of placing a satellite in orbit and transmitting radio signals from space.

Szputnyik1 was a hollow metal sphere about 58 cm in diameter, weighing 83.6 kg, with four external whip antennas. On board were a radio transmitter and a small power source; it transmitted at two radio frequencies, 20.005 and 40.002 MHz, producing a characteristic beeping signal that could be received on Earth. The signals were monitored by ground stations around the world, confirming an orbital regime and enabling tracking.

In operation, Szputnyik1 completed an initial low-Earth orbit with a perigee of about 215 km and an apogee of about 939 km, producing an orbital period of roughly 96 minutes. The satellite transmitted for about 21 days and completed approximately 1440 orbits before its transmitter failed. It remained in orbit until it reentered Earth's atmosphere and burned up on 4 January 1958.

Its launch signaled the start of human-made space exploration and had a profound impact on science policy and public imagination. The achievement spurred the United States to accelerate its own rocket and space programs, contributing to the eventual establishment of NASA and to ongoing international interest in space research.