Sputnik 1 was launched during the
International Geophysical Year from
Site No.1/5, at the 5th
Tyuratam range, in
Kazakh SSR (now known 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. It transmitted on 20.005 and 40.002
MHz,
[8] which were monitored by
amateur radio operators throughout the world.
[9] The signals continued for 21 days until the transmitter batteries ran out on 26 October 1957.
[4] Sputnik burned up on 4 January 1958 while reentering
Earth's atmosphere, after travelling about 70 million km (43 million mi) and spending three months in orbit.
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