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Sputnik 1

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, 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. Sputnik burned up on 4 January 1958 while reentering Earth's atmosphere, after three months, 1440 completed orbits of the Earth, and a distance travelled of about 70 million km (43 million mi).
Fearing the U.S. would launch a satellite before the USSR, OKB-1 suggested the creation and launch of a satellite in April¥May 1957, before the IGY began in July 1957. The new satellite would be simple, light (100 kg or 220 lb), and easy to construct, forgoing the complex, heavy scientific equipment in favour of a simple radio transmitter. On 15 February 1957 the Council of Ministers of the USSR approved this simple satellite, designated 'Object PS'. This version allowed the satellite to be tracked visually by Earth-based observers, and it could transmit tracking signals to ground-based receiving stations. The launch of two satellites, PS-1 and PS-2, with two R-7 rockets (8K71) was approved, provided that the R-7 completed at least two successful test flights.
The launch of the fourth rocket (8K71 No.8), on 21 August at 15:25 Moscow Time, was successful. The rocket's core boosted the dummy warhead to the target altitude and velocity, reentered the atmosphere, and broke apart at a height of 10 km (6.2 mi) after traveling 6,000 km. On 27 August, the TASS issued a statement on the successful launch of a long-distance multistage ICBM. The launch of the fifth R-7 rocket (8K71 No.9), on 7 September, was also successful, but the dummy was also destroyed on atmospheric re-entry, and hence needed a redesign to completely fulfill its military purpose. The rocket, however, was deemed suitable for satellite launches, and Korolev was able to convince the State Commission to allow the use of the next R-7 to launch PS-1, allowing the delay in the rocket's military exploitation to launch the PS-1 and PS-2 satellites.
A second, nationwide observation complex was established to track the satellite after its separation from the rocket. Called the Command-Measurement Complex, it consisted of the coordination center in NII-4 and seven distant stations situated along the line of the satellite's ground track. These tracking stations were located at Tyuratam, Sary-Shagan, Yeniseysk, Klyuchi, Yelizovo, Makat in Guryev Oblast, and Ishkup in Krasnoyarsk Krai. Stations were equipped with radar, optical instruments, and communications systems. Data from stations were transmitted by telegraphs into NII-4 where ballistics specialists calculated orbital parameters.
A fuel regulator in the booster also failed around 16 seconds into launch, which resulted in excessive RP-1 consumption for most of the powered flight and the engine thrust being 4% above nominal. Core stage cutoff was intended for T+296 seconds, but the premature propellant depletion caused thrust termination to occur one second earlier when a sensor detected overspeed of the empty RP-1 turbopump. There were 375 kilograms (827 lb) of LOX remaining at cutoff.
The Soviet Union agreed transmit on frequencies that worked with the United States' existing infrastructure, but later announced the lower frequencies. Asserting that the launch "did not come as a surprise", the White House refused to comment on any military aspects. On 5 October the Naval Research Laboratory captured recordings of Sputnik 1 during four crossings over the United States. The USAF Cambridge Research Center collaborated with Bendix-Friez, Westinghouse Broadcasting Co., and the Smithsonian Astrophysical Observatory to obtain a video of Sputnik's rocket body crossing the pre-dawn sky of Baltimore, broadcast on 12 October by WBZ-TV in Boston.