In the third and final orbit-raising operation conducted from Master Control Facility (MCF) at Hassan in Karnataka at 10:36 am today (March 16, 2007), INSAT-4B has been successfully placed in near-geosynchronous orbit. In today's manoeuvre, the Liquid Apogee Motor (LAM) on board the satellite was fired for a duration of 3 min 50 sec and the satellite has achieved an orbital period of 23 hours and 52 minutes.

It may be recalled that INSAT-4B was successfully launched by Ariane-5 on March 12, 2007 from Kourou, French Guyana. The launch vehicle had placed INSAT-4B in an orbit with a perigee (closest point to earth) of 250 km and apogee (farthest point to earth) of 35,886 km. The inclination of the orbit with respect to the equator was 4.5 deg. With two orbit raising manoeuvres conducted from MCF on March 13 and 14, 2007, the orbit of INSAT-4B had been raised to 32,878 km perigee and 35,736 km apogee with the orbital inclination reduced to 0.19 deg.

After placing INSAT-4B in near-geosynchronous orbit today, the deployment of its two solar panels and two antennas was successfully completed. The two solar arrays of INSAT-4B together generate 5,860 W of electrical power. The two antennas are used for various transmit and receive functions. The satellite will be put to its three-axis stabilised mode tomorrow.

INSAT-4B is presently located at 74.88 deg E longitude and is drifting towards its final orbital position of 93.5 deg E. The satellite drift will be arrested at 80.5 deg E longitude to carry out in-orbit testing of the payloads after which, it will be moved to 93.5 deg E longitude where it will be co-located with INSAT-3A.