Mars orbiter well on its way

This artist's concept of the Mars Reconnaissance Orbiter released by NASA features the spacecraft's main bus facing down, toward the red planet. After a seven-month journey, a NASA spacecraft closed in on Mars on Friday March 10, 2006 on a mission to examine the Red Planet in unprecedented detail from low orbit. The large silver circular feature above the spacecraft bus is the high-gain antenna, the spacecraft's main means of communicating with both Earth and other spacecraft. The long, thin pole behind the bus is the SHARAD antenna. Seeking liquid or frozen water, SHARAD will probe the subsurface using radar waves at a 15-25 MHz frequency band, "seeing" in the first few hundreds of feet (up to 1 kilometer) of Mars' crust. The large instrument (covered in black thermal blanketing) in the center is the HiRISE camera. This powerful camera will provide the highest-resolution images from orbit to date.

After the trajectory of India’s spacecraft to Mars was corrected on December 11, “everything is going well” and the orbiter “is well on course” towards the Red Planet, said K. Radhakrishnan, Chairman, Indian Space Research Organisation (ISRO).

“The Mars orbiter was more than four million km away as of yesterday. The spacecraft is in good health,” he said on Tuesday from Bangalore. Every day, precision ranging of the spacecraft was being done to know where exactly it was and how far away it was. Ground controllers from the ISRO Telemetry, Tracking and Command Network (ISTRAC) in Bangalore, and the Indian Deep Space Network (IDSN) at Byalalu, near Bangalore, were communicating with the spacecraft.

Since the Mars spacecraft had travelled more than four million km away, “there is a communication delay of 12 seconds” each way, Dr. Radhakrishnan said.

Three more corrections of the orbiter’s trajectory would be done when the ground controllers would command the eight, small thrusters on board the spacecraft to fire for setting right its trajectory so that the spacecraft is properly headed towards Mars. These course corrections would take place in April, August and September 2014.

The orbiter “is in a parabolic trajectory around the sun towards Mars” said Deviprasad Karnik, ISRO spokesperson. The spacecraft had to be “seen” continuously, that is, it should be monitored all the time. So ground controllers from ISTRAC and IDSN were communicating with it.

As of now, the ground controllers at the IDSN were communicating with the spacecraft, using the dish-antenna with a diameter of 18 metres. From April 2014, they would use the 32-metre antenna to keep a tab on it, Mr. Karnik said.

So far, the orbiter had not encountered any celestial object or space debris, Mr. Karnik added. ISRO’s Polar Satellite Launch Vehicle had put the Mars orbiter into an earth-bound orbit on November 5. After a prolonged firing of the spacecraft’s propulsion system on December 1, the orbiter winged out of its earth-bound into a sun-centric orbit.