India’s Indian Space Research Organisation (ISRO) launched its second navigation satellite today, April 4, at 11:44 UTC. A Polar Satellite Launch Vehicle (PSLV) rocket launched the IRNSS-1B spacecraft in a mission originating from the Satish Dhawan Space Centre.
Liftoff was on schedule. IRNSS-1B is the second of seven satellites that comprise the first-generation Indian Regional Navigation Satellite System (IRNSS). IRNSS-1B will join IRNSS-1A already in orbit in forming the first pair of satellites for the IRNSS.
Watch the launch in this video:
The IRNSS system will consist of three geostationary satellites and two pairs of spacecraft in inclined geosynchronous orbits. Each IRNSS satellite uses a rubidium-based atomic clock to keep time, transmitting signals on L and S-band frequencies at 1,176.45 and 2492.028 megahertz respectively. A C-band transponder and an array of retroreflectors will be used to determine ranging data for calibration, according to NASASpaceflight.com.