Molniya (satellite)
Molniya or when English paraphrase also Molniya (Russian Молния for flash, GRAU index: 11F67 ), is the name of Soviet and later Russian communications satellites that orbit the earth specifically to eccentric HEO orbits, here in Molniya orbit. The inclination is 63 °, the current time 718 minutes (about 12 hours). The perigee distance between 450 and 600 kilometers is located on the southern hemisphere. In apogee at a distance of 40,000 kilometers, the satellites move so slowly across the northern hemisphere according to Kepler's laws, that they are above the horizon for about eight hours. Four satellites allow continuous data transmission even in high latitudes, do not reach the geostationary satellites. The satellites are used for both civilian and military communication ( SECAM color television signal or 60 telephone channels or telegraphy or facsimile ).
After numerous trials, the first Molniya satellite ( Molniya -1) was launched on 23 April 1965. The satellite was tested to October 1967, with the launch of Molniya -1F and the orbital ground stations were put into operation during this period and the system officially declared ready for use. The satellites of this type consisted of a cylindrical hermetically sealed and filled with gas appliances section with conical statements containing the sensors and thrusters for attitude control. The energy is supplied by six solar boom. Are the cooling surfaces and a heating plate and a pair of diametrically oppositely oriented antenna dishes, one of which served as a replacement to the outside of the cylinder. They have a transponder in the frequency range of 1.0/0.8 GHz with a power of 40 watts at television broadcasts and otherwise 14 watts. The satellites were about 1000 to 1200 kg ( 1.6 tons at the start ), had a height of 4.4 m and a diameter of 1.4 m. The Molniya -2 satellites were further developed types that received 3.4 to 3.9 GHz frequency range and sent in the range 5.725 to 6.225 GHz. They had a similar configuration with enlarged cells booms and transferred video signals with 6 MHz bandwidth and an audio channel of 10 kHz mono or 6 kHz stereo, and parallel to the video signal has a frequency modulated with 150 kHz Audio-/Datenkanal. On November 22, 1974, the first Molniya -3 satellite was launched. These were, among others, for direct flights between Moscow and Washington. Since 1997, four satellites of the type Molniya -3K are in space. The launch of another satellite in July 2005 failed with a Molniya -M carrier rocket.
Versions
So far, the Molniya satellites were launched in five different Bauversionen.
- Molniya -1 ( 1964 )
- Molniya -1T ( from 1970)
- Molniya -2 ( from 1971)
- Molniya -3 ( from 1974 ) will
- Molniya -3K (from 1997 in use )
As followers of all standing still in use Molniya versions there is a new generation of satellites named Meridian. The first launch took place on 24 December 2006.