(Ding-year of leap August 11), October 4, 1957, the Soviet Union launched the first human artificial Earth satellite. Soviet satellites




in 1957, the world's first artificial Earth satellite has been produced by the Soviet Union successfully launched. The rocket carrying satellite satellite the necessary orbital velocity in meters per second, eight thousand. According to the calculation, the satellite at an altitude of 900 km above the ground running; every turn the whole week is 1 hour and 35 minutes, and the tilt angle between its orbit and the equatorial plane is 65 degrees.
satellites is a ball shape, a diameter of 58 cm, weight of 83.6 kg. Radio transmitter built two constantly radiate radio signal. Its frequency of 20.005 MHz and 40.002 MHz (wavelength of about 15 and 7.5 meters, respectively). The signal takes the form of a telegraph signal, each of the signal duration of approximately 0.3 seconds. Intermittently the same time with this. the
as early as the end of the 19th century, the outstanding Russian scientist Tsiolkovsky in his book the first scientifically demonstrated the possibility of achieving space flight with the rocket. the
Sputnik model, although only 55 cm in diameter, but it is a historic achievement