India's own GPS on track
launched its fourth navigation satellite, IRNSS-1D, from Sriharikota in Andhra Pradesh. This is part of the constellation of seven satellites to be put in place to roll out India's counterpart to the US-operated Global Positioning System (GPS). India's aim is to start its own satellite navigation system. According to scientists from the Time and Frequency Division of the Council of Scientific and Industrial Research (CSIR), IRNSS-1D is equipped with three atomic clocks which will keep track of time and guide IRNSS-1D users. "During calamities, we have to depend on the American GPS. Now, we are moving towards developing our own navigational system," said senior scientist Ashish Agarwal of CSIR's National Physical Laboratory.