TV has arrived and stayed in our everyday life, so we rarely reflect on the complexity of the processes lying beneath it. We’ve previously given a short technical overview on how TV signal is transmitted, but this time I’d like to settle on a more global topic and go a bit deeper into space, satellites, signals, antennas and orbit issues to remind you about the superhuman efforts that mankind has made for us to have television everywhere and anywhere.
Did you know that…?
- The word “orbit” in Latin means “track” or “path.”
- Orbits are classified into several types: upon inclination to equator (Inclined, equatorial and polar orbits) and upon height (Low Earth Orbit, Medium Earth Orbit, geosynchronous earth orbit, high-altitude orbit). Equatorial and geosynchronous orbit is called geostationary earth orbit.
- Geostationary orbit serves for the satellite television purposes. It is situated at a height of 35,786 km above the Earth’s surface. Other orbits are used for the needs of the military-industrial complex, satellite communications, meteorological services, navigation systems, various researching and other purposes.
- The first artificial Earth satellite was launched into an elliptical low Earth orbit by the USSR in 1957 (Sputnik-1, or Satellite-1).
- The first transatlanticsatellite transmission of a TV signal was held in 1962.
- Currently the geostationary orbit comprises of about 400 satellites, while the total number of satellites in the near-Earth space amounting to over 1,000.
- The modern satellite life cycle averages to be around 15 years and has limits by the amount of fuel on board which is required to periodically adjust its position on the orbit.
- Life-expired satellites are transferred to a disposal orbit (200 km above the geostationary orbit). These satellites along with other faulty or non-functioning artificial objects are referred to as “space” or “near-Earth” debris.
- Around 30 new satellites are launched into the geostationary orbit every year, while the life cycle of about 25 satellites launched before is expired.
- The further satellite receiving antennas are located from the equator, the lesser is the number of satellites available to receive the signal.
- Heavy rain is the bitter enemy of satellite TV signal reliable reception.
- The cost of launching a kilo of payload with a rocket vehicle Proton and upper-stage rocket Breeze-M to the geostationary orbit amounts to roughly $20,000USD.
