Mars Orbiter Mission crosses mid-point of its path to Mars

MOM crossed the mid-point of its path to Mars, on target to reach the Red planet on Sept 24

The Mars Orbiter Mission (MOM), India's first interplanetary exploration programme, today reached one of the major milestones. The Mars Orbiter spacecraft crossed the mid-point of its path to Mars.

Isro said that the Mars Orbiter Spacecraft crossed the half-way mark of its journey to the Red Planet along the

designated helio-centric trajectory.

ISRO has been continuously monitoring the Spacecraft using its Deep Space Network complemented by that of NASA-JPL. As the Spacecraft is on its designated trajectory, the TCM planned for April 2014 is not considered

essential. If required, the next TCM is planned to be carried out in June 2014, said Isro, adding that the Spacecraft and its five scientific instruments are in good health. Periodic tests are being done on the different levels of autonomy built into the Spacecraft for managing contingencies.

At present, the radio distance between the Spacecraft and the Earth is 39 million km. A signal from the Earth to the Spacecraft and back to Earth takes 4 minutes and 15 seconds. Soon, the High Gain Antenna of the

Spacecraft will be put in service for handling communications with the ground stations.

The Mars Orbit Insertion (MOI) manoeuvre would be performed on September 24, 2014.

Coincidently it happened just a day after the closest approach of Mars and Earth in their respective orbits which is called an opposition.

To a question, while shooting MOM if ISRO would have increased the angle, ( orbit of MOM) MOM could have reached Mars this time ( because Mars is near to Earth now ) why ISRO did not do that ? Isro in its FB account replied that, a Trans-Mars injection at an angle above the tangent of Earth's orbit will indeed take MOM to Mars in a shorter time. However, such a manoeuvre requires much larger velocity increment and thereby involves large fuel expenditure.

It means, less the number of TCMs, more the amount of propellant saved on-board MOM which will be put to good use later on during the extended phase of operations beyond the designated 6 month life span of the spacecraft around Mars, according to Isro's FB account.

India's first interplanetary spacecraft, Mars Orbiter was successfully launched on November 5, 2013 by India's Polar Satellite Launch Vehicle PSLV-C25, from Satish Dhawan Space Centre at Sriharikota.

On December 01, 2013, Trans Mars Injection manoeuvre was conducted successfully and the Spacecraft was set in its course towards Planet Mars through a helio-centric trajectory. Soon after the Spacecraft crossed the

sphere of influence of Earth, a Trajectory Correction Manoeuvre (TCM) was performed successfully on December 11, 2013.

Mars Mission (which was executed on only one third of Nasa's cost of Mars Mission and in first attempt itself it was lifted off while Nasa's first attempt failed) and the cryogenic engine development.