On this day in 1957—at the height of cold war tensions between the U.S.S.R. and the United States—the world’s first artificial satellite Sputnik 1 was launched by the Soviet Union. Here are a few interesting facts:
Sputnik 1 was a 58 cm (23 in) diameter polished metal sphere, with four external radio antennas to broadcast its radio signals.
The lead designer of Sputnik 1 was M. S. Khomyakov.
The launch coincided with the 102nd anniversary of the Wright brothers’ first powered, controlled flight.
Sputnik 1 was launched aboard a Soviet R-7 rocket, during the International Geophysical Year from Site No.1/5, at the 5th Tyuratam range, in Kazakh SSR (known now as the Baikonur Cosmodrome).
The satellite travelled at about 29,000 kilometres per hour (18,000 mph; 8,100 m/s), taking 96.2 minutes to complete each orbit. The pre-launch trajectory was calculated by Georgi Grechko, using the USSR Academy of Sciences‘ mainframe computer.
After the first orbit the Telegraph Agency of the Soviet Union (TASS) issued a press release: “As result of great, intense work of scientific institutes and design bureaus the first artificial Earth satellite has been built”.
Sputnik 1 transmitted on 20.005 and 40.002 MHz: these frequencies were chosen for the ease with which they could be monitored by amateur radio operators throughout the world. The signals continued for 22 days until the transmitter batteries ran out on 26 October 1957.
It continued to orbit the Earth for another three months, travelling approximately 70 million km (43.5 million miles) before burning up in the atmosphere during reentry on January 4, 1958.