December 24, 2005 

INSAT-4A was launched by European Ariane-5 launch vehicle on December 22, 2005 from Kourou, French Guyana. The launch vehicle had placed INSAT-4A in an orbit with a perigee (closes point to the earth) of 622 km and apogee (farthest point to earth) of 36,152 km. The first orbit raising manoeuvre carried out from MCF, Hassan yesterday (December 23, 2005) had put the satellite in an intermediate orbit of 13733 km perigee and 36,008 km apogee.

In the second orbit raising manoeuvre conducted at 13.24 (IST) today (December 24, 2005), the Liquid Apogee Motor (LAM) on board INSAT-4A was fired for 42 minutes by commanding the satellite from Master Control Facility (MCF), Hassan. With this LAM firing, INSAT-4A perigee (closest point to the earth) has been raised to 31479 km. The apogee height remains at 36,008 km and the inclination of the orbit with respect to the equatorial plane has been reduced from 0.85 deg to the present 0.12 deg. INSAT-4A now has an orbital period of 22 hours 13 minutes. The satellite will now be in the continuous radio visibility of MCF-Hassan.

The satellite came within the radio visibility of MCF this morning at 07.19 am (IST) and all the necessary operations like earth acquisition and gyro calibration were carried out before the second orbit raising manoeuvre was started.