India's Mars Orbiter ready to part with earth

India's maiden spacecraft to Mars is ready to part with earth an hour after Saturday midnight and get into the sun's orbit for its long voyage to the red planet, scientists said Friday.

"The Mars Orbiter is ready for the crucial slingshot after midnight when its liquid engine will be fired at 12.49 a.m. Sunday to leave the earth orbit and enter the solar orbit after 23 minutes at 1.12 a.m," a senior space agency scientist told IANS.

About 200 scientists and technicians are glued to the control panels in the Mars mission complex at the Telemetry, Tracking and Command Network (Istrac) of the state-run Indian Space Research Organsiation (ISRO) here, monitoring the Orbiter in its last lap of the earth's orbit at an apogee (farthest from equator) of 192,915km.

"Performance assessment of all subsystems of the spacecraft has been completed. The Orbiter is ready for the trans-Mars injection, which will make it escape the earth's sphere of influence (gravitational pull) and leap into the sun orbit in a trajectory to traverse 680 million km during the nearly 10-month voyage and reach the Martian orbit Sept 24, 2014," ISRO scientific officer V. Koteshwar Rao told IANS.

Transition from the earth's final orbit to solar orbit has been programmed in line with sun's gravity and laws of the universe to ensure Orbiter reaches precisely on time to sling into the Martian orbit after 280 days.

"The engine will be fired for 23 minutes with onboard fuel to give an incremental velocity (speed) of 648 metres per second to the Orbiter and a series of commands will be given in advance to leap into the heli-centric phase for its space odyssey towards Mars," Rao said.

India will become the first Asian country and fourth nation in the world to leap into the interplanetary space with its Rs.450-crore exploratory mission to Mars, about 400 million km from earth.

The 1,337kg Orbiter was launched Nov 5 from Sriharikota spaceport off the Bay of Bengal, about 80km north east of Chennai, onboard a 350-tonne rocket with five scientific instruments to detect methane in the Martian atmosphere, measure the thermal emission and capture images of the red planet from its orbit at a distance of 500km.

"The trans-injection exercise is a complex combination of navigation and propulsion technologies, governed by the gravity of sun and Mars," Rao said.

As the fourth planet from sun and behind earth, Mars is the second smallest celestial body in the solar system. Named after Roman god of war, it is also known as red planet due to the presence of iron oxide in abundance.

Though earth and Mars have equal period of revolution around their axis, the red planet takes 24 hours and 37 minutes to complete a revolution. Earth takes around 365 days to orbit the sun and Mars 687 days.