The Mars Orbiter Mission (MOM) has crossed and gone beyond the Sphere of Influence of Earth on Wednesday early morning.
Isro has explained Sphere of Influence stating that the Sun is much more massive than any of the planets and its gravity dominates the Solar System. Only very near to the planets, the planetary gravity become stronger than that of the Sun. This region around the planet is referred to as the Sphere of Influence (SOI) of that planet.
Sun's sphere of influence is the region where the gravity of Sun dominates as compared to the rest of the galaxy. This region extends up to about two light years which is well beyond the orbit of Pluto. SOI of Earth is 9.25 lakh km. Orbits of the Moon and all the artificial satellites of Earth fall inside this sphere.
A day after successfully crossing the Earth's Orbit, on Tuesday morning, MOM crossed the distance of Moon's orbit on December 2. MOM is now the farthest object sent into space by India.
On December 1, India joined interplanetary travelers, after successfully conducting a critical manoeuvre to place the Mars orbiter spacecraft in the Mars transfer trajectory. Country's first mission to Mars left Earth's orbit in the early hours of Sunday, clearing a critical hurdle in its journey to the red planet, which could not be succeeded by the emerging rival Chinese agency.
India is the first Asian country and fourth nation in the world to leap into the interplanetary space.
Isro Chairman K Radhakrishnan earlier said, on December 11 Isro will conduct first small mid course correction manoeuver, subsequently one will be in April and another one in August next year.
These are all ensure that on September 24, 2014, when we are near the Mars, we are at 500 plus or minus 50 kms, he said.
Two weeks before reaching Mars, there will be one more manoeuver. So there will be four correction manoeuvers. Next crucial event is on September 24, 2014, which is the insertion of the spacecraft into Mars' orbit.
To a question on life of spacecraft, Isro said life of a spacecraft is determined by the amount of fuel it carries, the reliability of the components used, life of the solar arrays on-board etc. These days, before spacecraft runs out of fuel, one last command will be given to de-orbit or push the spacecraft into a graveyard orbit.
