China adds two more satellites to its global positioning system

BBC : With the launch yesterday of two more navigation satellites, China is another step closer to having its own global positioning system. Since 2000, China has put 13 of the 35 planned satellites into orbit. Once its Beidou system , also known as Compass, is completed in 2020, China will join the US, Russia, and Europe in having its own GPS. With the system now partially operational, China hopes to depend less on the US system, which controls a large share of the GPS market and could be disabled by the US government in the event of a conflict.