Ahead of India's Mars orbiter's scheduled rendezvous with the red planet on September 24, ISRO is all set for the crucial fourth trajectory correction manoeuvre and test fire of the main liquid engine on the spacecraft on Monday.
The 440 Newton Liquid Apogee Motor (LAM) engine now in an idle mode on the Mars Orbiter Mission for 300 days will be fired for about four seconds which, if successful, will boost the confidence level of ISRO about the success of insertion of the spacecraft into the Martian orbit.
"We are all set for the fourth trajectory correction manoeuvre and test fire of the main liquid engine, commands have already been loaded into the spacecraft for this event and has also been verified," a top ranking ISRO official said.
He said the event is crucial as the engine stored in the orbit for about 300 days without operation will be restarted for testing.
"This test firing of the LAM engine is like a trial, which is going to be fired for a longer duration on September 24 for Mars Orbit Insertion," he said. The engine will be test fired for 3.968 seconds with fuel consumption of about 0.567 kg and with a decremental velocity of 2.142 meters/second.
The MOM, India's first interplanetary mission launched on November 5, 2013, by India's workhorse Polar Satellite Launch Vehicle from the spaceport of Sriharikota in Andhra Pradesh, will enter into Sphere of Influence of Mars.
On a 666 million km journey, the spacecraft escaped the earth gravity pull on December 1, 2013.
In case of any problem in tomorrow's manoeuvre, ISRO said it is ready with Plan B where in eight thrusters alone will be firing for a longer duration, probably consuming more fuel, and try to get in orbit around Mars.
In a critical act in the final moments on September 24, the orbiter has to be slowed down from 22.1 km per second to 4.4 km per second in relation to the red planet to be captured by the Martian orbit for the mission to be declared a success. The engine would be fired for 24 minutes on that day to reduce its velocity and insert it into the Martian orbit.
If the Rs 450 crore MOM mission turns out to be a success, ISRO would be the fourth space agency in the world to have sent a mission to Mars. European Space Agency (ESA) of European consortium, National Aeronautics and Space Administration (NASA) of the US and Roscosmos of Russia are the only three agencies which have so far sent their missions to the red planet.
Only 21 of the total of 51 missions sent to Mars by various countries have been successful.
If the final moments on September 24 are a success, India would be the first Asian country to go to Mars and also the first to succeed in the maiden attempt.
ISRO would utilise four ground stations for the operation --- Indian Deep Space Network (IDSN) at Byalalu near Bangalore, Goldstone in USA, Madrid in Spain and Canberra in Australia.
