when was this satellite launched?
4 October 1957
Introduction
 The Soviet Union launched it into an elliptical low Earth orbit on 4 October 1957.
who was the leader of the soviet union when sputnik was launched Nikita Khrushchev
4 October 1957 4 October 1957. October 1957
Sputnik 1 Sputnik 1 Sputnik 1
Launch and mission Introduction Introduction
 4 October 1957 Sputnik 1 (; "Satellite-1", or "PS-1", Простейший Спутник-1 or "Prosteyshiy Sputnik-1", "Elementary Satellite 1") was the first artificial Earth satellite. The Soviet Union launched it into an elliptical low Earth orbit on 4 October 1957.  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 , taking 96.2 minutes to complete each orbit. It transmitted on 20.005 and 40.002 MHz, which were monitored by radio operators throughout the world. The signals continued for 21 days until the transmitter batteries ran out on 26 October 1957.
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Sputnik 1 [SEP] Introduction
Sputnik 1 (; "Satellite-1", or "PS-1", Простейший Спутник-1 or "Prosteyshiy Sputnik-1", "Elementary Satellite 1") was the first artificial Earth satellite. The Soviet Union launched it into an elliptical low Earth orbit on 4 October 1957. It orbited for three weeks before its batteries died and then orbited silently for two months before it fell back into the atmosphere. It was a polished metal sphere 58 cm (23 in) in diameter with four external radio antennas to broadcast radio pulses. Its radio signal was easily detectable by radio amateurs, and the 65° inclination and duration of its orbit made its flight path cover virtually the entire inhabited Earth.