First MOM trajectory correction manoeuvre planned for Dec 11

As India's maiden mission to Mars continues its fuel-less cruise to the Red Planet, ISRO would this week carry out further manoeuvres aimed at keeping the spacecraft in the intended trajectory.
The first of the four Trajectory Correction Manoeuvres (TCM) would be carried out on December 11, Indian Space Research Organisation (ISRO), which launched the Mars Orbiter Mission (MOM) on November 5, said today.
Though the spacecraft is moving towards the Red Planet in the intended trajectory, four TCMs are planned to fine tune it so as to keep it in the precise intended track.
"We have already imparted the velocity required by MOM to reach Mars during the Trans-Mars Injection (on December 1) and now MOM is cruising with a velocity of about 32.8 km/s. The first TCM is scheduled on December 11," ISRO sources told PTI.

The propulsion system of MOM, which is to travel a total distance of about 680 million km, will be using monomethyl hydrazine as fuel and dinitrogen tetroxide as oxidizer during all the four TCMs, they said.
Interacting with space enthusiasts in its official page on social networking site Facebook, ISRO said MOM was not taking the shortest route to the Red Planet, since accelerating and later decelerating to match the planet's speed would require an extremely large amount of fuel in that option.

"The route which requires the least amount of fuel is an elliptical orbit which forms a tangent to the Mars' and Earth's orbit around the Sun. MOM is travelling a distance of about 680 million km in this elliptical trajectory. This kind of transfer is called a Hohmann transfer," ISRO said, adding this helped in use of less fuel.

ISRO also said that the targeted mission life of MOM was six months after Mars Orbit Insertion.
"Fuel is required even in Martian orbit for orientation control of the spacecraft. The mission can be extended if such non-renewable resources in the spacecraft last longer," it said.