China launches third orbiter for indigenous global satellite navigation system

  China successfully launched an orbiter into space from the Xichang Satellite Launch Center in southwestern Sichuan province at about 0:12 a.m. Beijing Time on Sunday.

  It was the third orbiter that China has launched for its independent satellite navigation and positioning network, also known as Beidou, or Compass system.

  The new satellite was boosted by a Long-March-3III carrier rocket into a geostationary orbit.

  It will join another two already in orbits to form a network which will eventually have a total of 35 satellites, capable of providing global navigation service to users around the world around 2020.

  According to plan, the Beidou system will provide navigation, time signal and short message services in Asian and Pacific regionaround 2012.

  The COMPASS system will provide both open and authorized services, according to China's satellite navigation project center.

  The open service will be free of charge for the system's users within service area with a resolution of 10 meters for positioning,an accuracy of 10 nanosecond for time signal and an accuracy of 0.2 meter per second for speed measurement.

  The authorized service will provide more accurate services for authorized users.

  China started to build up its own satellite navigation system to break its dependence on the U.S. GPS system in 2000 when it sent two orbiters as a double-satellite experimental positioning system, known as the Beidou system.

  The Beidou system, China's first-generation satellite navigation and positioning network, made the country the third in the world after the U.S. and Russia to have an independent satellite navigation system.

  The original Beidou system provide regional service for telecom,transport and disaster relief within the country, and has played important roles especially in the Beijing Olympics and relief workfor the 8.0-magnitude Wenchuan earthquake.

  China started to upgrade the Beidou system into the second-generation system by launching two new orbiters into space in 2007 and 2009 respectively.