In a major achievement, the Giant Metre-wave Radio Telescope at Khodad detected and tracked the landing of a European Space Agency spacecraft on a Mars mission

Driving from Pune to Nashik, one is greeted by a variety of landscapes – mountains at a distance, villages, towns, even a brief stretch of a jungle and a river.

As one progresses, one enters the town of Narayangaon, a-not-tooclean-place which is known to space scientists and astronomers, not only from India, but from other countries too. It is just another small town and quite understandably one may wonder why it is known to the scientific community. Go a little further and at one point the road bifurcates – the one going ahead is for Nashik and the road turning right takes one to a narrow cobbled stretch. Pass through the fields, villages and old structures, suddenly at a distance the sight of an enormous dish antenna greets you. Sure, it is an awesome sight. We are approaching the town of Khodad – the home of the Giant Metrewave Radio Telescope (GMRT), which is part of the Tata Institute of Fundamental Research.

Narayangoan is the last big town before GMRT, and for those coming from Pune which is usually the case, it has almost become the gateway to the hi-tech facility. The scenario has a tinge of irony because GMRT, which aims for the stars, is surrounded by a landscape which carries no sign of development. The picture is in total contrast.

At the entrance of GMRT, there is a huge board welcoming visitors. But, do not get misled because one cannot have an easy access to the place. At the gate there is a security check which is done politely and once you are cleared to enter your mobile phone has to be deactivated. Throughout your stay at GMRT, there is no way one can use mobile phones as it may interfere with the working of the radio telescopes.

The GMRT has been described as the world’s largest fully operational low frequency radio telescope.

Consisting of 30 dish antennas, each of 45 metre in diameter, it is spread out over a region of almost 25 kms. Of the 30, 14 are located more or less randomly in a central region, while the remaining 16 are placed along the three arms of a ‘Y’ shaped configuration over a much larger region.

The GMRT project, a brain child of Govind Swarup, the father of Indian radio astronomy, has for more than a decade been detecting ground-breaking astronomical activities which has won global acclaim. On account of its reputation it has been attracting astronomers from all over the world and many are in a queue to use the facility to do research.

The first observations of GMRT were done with a test system in 1997 and it came into regular use from 1998. On October 4, 2001, it was declared open to the international community. Coincidentally, it was on this very day in 1957, that the world rocketed into the space age with the launch of Sputnik by the former Soviet Union.

India and China may have political differences, but it has apparently not impacted the scientific community of both the nations, especially the space scientists. How else does one explain the fact that Chinese astronomers have sent 14 research proposals to date for consideration. Some of the other countries which have evinced keen interest in the GMRT facility are Chile, Iran, Taiwan, Nigeria and South Africa.

It was the first telescope in the world to survey a certain type of astronomical activity. GMRT has been used to uncover interesting new results on normal and active galaxies. Various groups have used the facility to carry out deep surveys of specific regions of the sky to obtain detailed properties of what is known as “extragalactic” sources Keeping in view the future demands, GMRT has been upgraded.

Till now, the GMRT was essentially an observatory surveying the skies to uncover some new and unusual astronomical activity. But, on the night of October 19, 2016, the GMRT did a different type of monitoring which is historical, endorsing the scientific credentials of India.

It was chosen by none other than Nasa to monitor and receive signals from the European Space Agency’s (ESA) Schiaparelli lander while it zoomed towards Mars at a whopping speed of 21,000 kmh and touched down on the Red Planet.

This correspondent, who was present in the GMRT’s control room on that historical night, witnessed the thrill and excitement of a Mars mission in real time and subsequently the disappointment when Schiaparelli failed to transmit a signal after touchdown.

From 6 pm onwards on October 19, scientists were glued to the computers monitoring every aspect of the nail-biting flight. As the moment neared for the entry of the spacecraft to Mars, the control room started getting packed with scientists, all exchanging remarks in a hushed voice about the data being flashed on the computers.

There were cheers and applause when it was confirmed that Schiaparelli’s parachute was deployed flawlessly without a hitch prior to its much-awaited landing, but this festive mood turned grim when the lander did not send a signal after landing at 8.27 pm. The scientists waited for some time in the control room hoping that that Schiaparelli will say “hello”. When no word came, they walked out feeling disappointed, speculating what could have gone wrong with the spacecraft.

Stephan Esterhulzen of Nasa’s Jet Propulsion Laboratory (JPL), who was constantly in touch with his institution – JPL – and the European Space Operations Centre (ESOC) at Darmstadt in Germany – during the flight, described GMRT as an excellent world-class facility.

“We were the first to receive all the signals from Schiaparelli,” he said. It was from here that the signals flashed in a second to ESOC and JPL.

GMRT director Swarna Ghosh said that it was selected by Nasa for the European Mars Mission because of its sensitivity and some technical advantages over other similar global facilities. “This is the first time that GMRT has been used for a space mission,” he observed while stressing that it was executed flawlessly.

About the failure of Schiaparelli to transit a signal, GMRT dean Yeshwant Gupta said, “It is a real pity that 99 per cent of its journey was completed, unfortunately it did not finish that one per cent.” “However, it was a historic day for us at GMRT because it proved its worth by providing precise data,” he said. According to him, the fact that GMRT had proved its worth with the Mars flight does not rule out the possibility that it may come into the picture in future space missions.