Rahul M wrote:>> But nobody has answered my question. Space gurus please share some gyan.
not a space guru by any means but I guess the reason is tidal forces.
In the first 3 orbits, I don't think lunar and solar gravitational forces vis-a-vis earth's attraction are significant enough. Even if it were, the force exerted by the sun would be greater than the moon. So I would rather have the sun's gravitational forces and the earth's gravitational forces in the opposite direction at the perigee, while increasing the velocity of the craft. Therefore, it would have been better to do it during the day. Instead they chose do it at night. So, either I am missing something fundamental or this is not the case.
My only guess was that they wait for the situation when the Indian landmass is towards the perihelion while the spacecraft is nearing the perigee, to insure uninterrupted communication link.