ISRO launched fifth GPS Satellite which is part of a series of 7 satelites. the first satellite was launched in July 2013.Two more such satellites will be launched in the next two month and with this  India’s Desi regional navigation system will be operational.Four satellites launched earlier are already operational.  While four satellites are sufficient to start operations of the IRNSS system, the remaining three are needed to make the signal available all time with both accuracy and precision.The satellites continuously beam  data that can be read by hand-held instruments or smart phones with a 20 metres accuracy standards. India is now in the elite club  after USA, Russia and China to have a satellite-based navigation system.This GPS system will have an error margin of no more than 20 metres. It will cover a region of about 1,500 km from India’s borders in the region from which the India consider a threat perception.It was ISRO’s 33rd  PSLV launch and the first this year.

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