IRNSS 1D is the fourth in the series of seven satellites, the national space agency is planning to launch to put in place the Indian Regional Navigation Satellite System (IRNSS). While four satellites would be sufficient to start operations of the system, the remaining three satellites would make it more accurate and efficient. The other launches also relate to the IRNSS series with the IRNSS1E and IRNSS1-F satellites to be launched before the year end. Read more via Indian Express
