<P> A fuel regulator in the booster also failed around 16 seconds into launch, which resulted in excessive RP - 1 consumption for most of powered flight and engine thrust 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 . </P> <P> At 19.9 seconds after engine cut - off, PS - 1 separated from the second stage and the satellite's transmitter was activated . These signals were detected at the IP - 1 station by Junior Engineer - Lieutenant V.G. Borisov, where reception of Sputnik 1's "beep - beep - beep" tones confirmed the satellite's successful deployment . Reception lasted for two minutes, until PS - 1 fell below the horizon . The Tral telemetry system on the R - 7 core stage continued to transmit and was detected on its second orbit . </P> <P> The designers, engineers and technicians who developed the rocket and satellite watched the launch from the range . After the launch they drove to the mobile radio station to listen for signals from the satellite . They waited about 90 minutes to ensure that the satellite had made one orbit and was transmitting, before Korolev called Soviet premier Nikita Khrushchev . </P> <P> On the first orbit the Telegraph Agency of the Soviet Union (TASS) transmitted: "As result of great, intense work of scientific institutes and design bureaus the first artificial Earth satellite has been built". The R - 7 core stage, with a mass of 7.5 tonnes and a length of 26 meters, also reached Earth orbit and was visible from the ground at night as a first magnitude object following the satellite . Deployable reflective panels were placed on the booster in order to increase its visibility for tracking . The satellite, a small, highly polished sphere, was barely visible at sixth magnitude, and thus more difficult to follow optically . A third object, the payload fairing, also achieved orbit . </P>

Who was the leader of the soviet union when sputnik was launched