MARS MISSION SYMBOLISES INDIA’S ASSURED ACCESS TO SPACE

MARS MISSION SYMBOLISES INDIA’S

ASSURED ACCESS TO SPACE

T. S. SUBRAMANIAN

The Polar Satellite Launch Vehicle (PSLV-C25) successfully putting the 1,350-kg Mars Orbiter first into its earth-bound orbit on Tuesday “symbolised India’s assured access to space” and it proved that “we can do any type of mission,” said S. Ramakrishnan, Director of Vikram Sarabhai Space Centre in Thiruvananthapuram. “With meticulous planning and team work, no mission is beyond our capability.”Not only Mr. Ramakrishnan, P. Kunhikrishnan, Mission Director of PSLV-C25; M.C. Dathan, Director of Liquid Propulsion Systems Centre; M.Y.S. Prasad, Director of Satish Dhawan Space Centre;, A.S. Kiran Kumar, Director of Space Applications Centre, Ahmedabad; and S.K. Shivakumar, Director of ISRO Satellite Centre, Bangalore, said it was the hard work and dedication of hundreds of personnel in various ISRO centres that led to the PSLV placing the Mars orbiter precisely into its orbit.ISRO Chairman K. Radhakrishnan praised the contribution of M. Annadurai and V. Kesavaraju, who were in Bangalore on Tuesday, to the project.

Mr. Ramakrishnan said the Mars orbiter being placed in earth-bound orbit marked ISRO’s “first step” in India’s ambitious mission to send a spacecraft to Mars. “But it is a difficult step because several systems have to work precisely to take the spacecraft from the earth into orbit. Besides, energy-wise, what the spacecraft takes to go to Mars is only a fraction of the percentage that it took to enter into earth-orbit.”The PSLV-C25 used 250 tonnes of propellants to put the Mars orbiter into its near-earth orbit with a perigee of 246.9 km and an apogee of 23,566 km. But from the earth-bound orbit to its Mars orbit, the spacecraft will use only 850 kg of propellants on its board.ISRO scientists said there would be five firings of the 440 Newton engine on board the Mars Orbiter to gradually increase its apogee. The first firing would take place early in the morning of November 7. A prolonged firing on December 1, 2013 would catapult the spacecraft out of its earth-bound orbit into Sun-centric orbit. It would then go around the Sun in such a way as to coast along for nine months and then rendezvous with Mars. On September 24, the engine would again be fired to slow down the spacecraft’s velocity and it would be reoriented to enter the Mars orbit with a peri-apsis of 365 km and an apo-apsis of 80,000 km.

Dr. Radhakrishnan emphasised that the “primary objective of the Indian mission has been to put our spacecraft into the Martian orbit.”“Mars orbiter has five scientific payloads, all built by the ISRO centres. It has a colour camera for optical imaging of the Earth’s surface; a methane sensor; a thermal infrared camera to study geological activity; a Lyman Alpha Photometer to study the Martian atmosphere; and a payload to study the neutral composition of the planet’s upper atmosphere.”Future ISRO missions included a GSLV with an indigenous cryogenic engine in December 2013, an all-Indian Chandrayaan-2 mission with an indigenous lander and rover in 2015/2016; Aditya to study the Sun’s corona and so on.”

Prof. John Kurakar