Communication satellite INSAT-4B in Near-Geosynchronous Orbit

Bangalore, Mar 16: Indian communication satellite INSAT-4B has been successfully placed in the near geosynchronous orbit after the third and final orbit raising operations was today carried out by the Master Control Facility (MCF) of the Indian Space Research Organisation (ISRO) at Hassan in Karnataka.

The satellite's two solar panels and two antennae have also been deployed, ISRO said in a release here.

In today's manoeuvre, the Liquid Apogee Motor (LAM) on board the satellite was fired for a duration of three minutes 50 seconds and the satellite had achieved an orbital period of 23 hours and 52 minutes, ISRO said.

INSAT-4B was successfully launched by Ariane-5 on March 12 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, 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.

The two solar arrays of INSAT-4B together generated 5,860 KW of electrical power. The two antennae were used for various transmit and receive functions. The satellite would be put on its three-axis stabilised mode tomorrow, ISRO said.

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

UNI