NEW DELHI: Prime Minister Narendra Modi today congratulated scientists for the successful launch of IRNSS-1D satellite, saying "it is yet another manifestation of their exemplary efforts.""Launch of satellite IRNSS-1D is yet another manifestation of the exemplary efforts & utmost brilliance of our scientists. Congrats to them," he tweeted.With the succesful launch of IRNSS-1D, the fourth in the series of seven navigational satellites today, India is set to operationalise its own navigational system on part with the GPS of the United States.IRNSS-1D will provide navigation, tracking and mapping service and has a mission life of 10 years.It is the fourth in the constellation of seven satellites, planned by ISRO to constitute IRNSS, which would be on par with US-based GPS once the full complement of spacecrafts are launched.While four satellites would be sufficient to start operations of the IRNSS system, the remaining three would make it more accurate and efficient.