The control system of the Sputnik Rocket was tuned to provide an orbit with the following parameters: perigee height - 223 km (139 mi), apogee height - 1,450 km (900 mi), orbital period - 101.5 min.[39] A rocket trajectory with these parameters was calculated earlier by Georgi Grechko,[40] after completing the calculations over several nights on the USSR Academy of Sciences's mainframe computer.[20]
The Sputnik Rocket was launched at 19:28:34 UTC, on 4 October 1957, from Site No.1 at NIIP-5.[41] Processing of the information, obtained from the "Tral" system showed[20] that the side boosters separated 116.38 seconds into the flight and the second stage engine was shut-down 294.6 seconds into the flight.[39] At this moment the second stage with PS-1 attached had a height of 223 km (139 mi) above Earth's surface, a velocity of 7,780 m/s (25,500 ft/s) and velocity vector inclination to the local horizon was 0 degrees 24 minutes. This motion resulted in an orbit with initial parameters: perigee height - 223 km, apogee height - 950 km (590 mi), initial orbital period - 96.2 minutes.[39]
After 314.5 seconds PS-1 separated from the second stage[39] and at the same moment at the small "Finnish house" of IP-1 station Junior Engineer-Lieutenant V.G.Borisov heard the "Beep-beep-beep" signals from the radio receiver R-250. Reception lasted for two minutes, while PS-1 was above the horizon. There were many people in the house, both military and civil, and they were probably the first to celebrate the event.[20][42] After 325.44 seconds a corner reflector on the second stage was opened, that also allowed measurement of its orbit parameters - like the working "Tral" system did.[29]
The designers, engineers and technicians who developed the rocket and satellite watched the launch from the range.[43] After the launch they ran to the mobile radio station to listen to signals from the satellite.[43] They waited about 90 minutes to ensure that the satellite had made one orbit and was transmitting, before Korolyov called Khrushchev.[44] The downlink telemetry included data on temperatures inside and on the surface of the sphere.
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".[45] The Sputnik 1 rocket booster (second stage of the rocket) also reached Earth orbit and was visible from the ground at night as a first magnitude object following the satellite. Korolyov had intentionally requested reflective panels placed on the booster in order to make it so visible.[44] The satellite itself, a small but highly polished sphere, was barely visible at sixth magnitude, and thus more difficult to follow optically. Ahead of Sputnik 1 flew the third object - the payload fairing, 80 cm (31 in)-long cone, i.e. a little bit bigger than the satellite.
No comments:
Post a Comment