Remembering Mangalyaan

Source: By Arjun Sengupta: The Indian Express

Earlier this year, the Indian Space Research Organisation (ISRO) successfully soft-landed Chandrayaan-3 on the lunar south pole in what was a major leap forward for Indian space exploration.

Another such leap was taken exactly nine years ago, on 24 September 2014, when the Mars Orbiter Mission (MOM), informally referred to as Mangalyaan, successfully entered into orbit around the Red Planet.

This was India’s first tryst with interplanetary travel and a somewhat unlikely success — prior to ISRO, no other space agency had successfully managed to orbit the Red Planet in its first attempt. Moreover, ISRO became just the fourth space agency — after the US’s NASA, Russia’s ROSCOSMOS, and the European Space Agency — to accomplish this feat. And it did so in a record low cost of Rs 450 crore (approx $73 million), $25 million less than the budget of the Matt Damon starrer The Martian (2015).

While the orbiter had a planned mission duration of just six months, it stayed in touch with Earth till April 2022, when communications were finally lost, possibly due to an exhaustion of fuel resources.

Looking ahead after Chandrayaan-1

Chandrayaan-1, India’s first (and successful) attempt at sending a spacecraft to the moon, was launched at Sriharikota on 22 October 2008, entering lunar orbit on 8 November that year. The orbiter also dropped a Moon Impact Probe (MIP) on the lunar surface, making it the first Indian-made object to touch the moon. For ISRO, Chandrayaan-1 was a massive success.

The Indian flag on the MIP inscribed India’s presence on the Moon forever, heralding the nation’s entry into the elite club of the countries that had earlier placed national flags on the Moon (the USA, Russia and China), G Madhavan Nair, then ISRO director, wrote in his autobiographical book Rocketing Through the Skies: An Eventful Life at ISRO (2023).

But bigger, more difficult things would soon be in play. Mars has always been an object of interest for scientists and astronomers across the world. For people working at ISRO, things were no different. But with the success of Chandrayaan-1, there was a new energy and vigour with which this task was approached. ISRO had proved itself as one of the most capable space agencies on the planet. Now it was time for it to stretch its limits.

A mission blueprint is prepared

A Mars Mission Study Team was constituted under Chairman K Radhakrishnan in August 2010 to provide a feasible blueprint on what a mission to the Red Planet would actually look like. Various kinds of Mars missions were discussed, including fly-by, orbiter, lander-rover, and even balloons, airplanes, sub-surface explorers, sample return missions.

It turned out that a fly-by, which gives only a short time for scientific study [was] not really attractive. On the other hand, an orbiter or a lander would require larger transportation capability that may not be met by the established and reliable launch systems [available at the time], V Adimurthy, the Mission Concept Designer for MOM, wrote in From Fishing Hamlet to Red Planet (2015).

Never afraid of a challenge, ISRO decided upon an orbiter mission, to be launched aboard its tried-and-tested workhorse — the PSLV. “We discovered that we can have a highly elliptic orbit mission around Mars using our proven PSLV launch system,” Adimurthy wrote.

The study team submitted its report, with all details of a potential Mars Mission in June 2011, which was followed by a series of reviews at various levels. Finally, the mission was announced by then Prime Minister Manmohan Singh on 15 August  2012, during his independence day speech.

An extremely tight deadline

But this left an extremely tight window within which ISRO had to launch the orbiter. The launch had to be made by November 2013-January 2014, failing which, the next launch opportunities for a fuel-saving Hohmann transfer orbit would be in 2016 and 2018. In fact, the 2013 opportunity was by far the best option available.

Among the next two minimum-energy Earth departure opportunities, Mars missions in November 2013 and January 2016, the first opportunity of 2013 was found to be the better one requiring about 380 m/s less velocity. This is very significant with respect to the utilisation of PSLV as the launch system. We could do a reasonably good Mars Orbiter Mission with PSLV in 2013 but not in 2016,” Adimurthy wrote.

Moreover, this was a challenge unlike anything ISRO had thus far encountered. The travel time for MOM to reach Mars orbit would be around 300 days. Moreover, given the distance that the craft would cover, real-time interventions from ISRO scientists would be impossible. Hence, as Adimurthy explained: “on-board autonomy had to be provided for all critical operations.”

But the biggest challenge would be inserting the orbiter into Mars orbit. “Restart of the propulsion system, after nearly a year of travel in space, for Mars orbit capture manoeuvre was a major technical challenge,” Admurthy explained.

A successful launch and a pioneering mission

Despite a multitude of challenges, Mangalyaan was prepared in a record 15 months — partly due to using a reconfigured lunar orbiter prepared for the Chandrayaan mission. After a brief delay as ISRO’s tracking ships were unable to take up their pre-determined position near Fiji due to inclement weather, MOM was launched aboard a PSLV-XL on 5 November 2013. And after a 298-day transit, it was put into Mars orbit on 24 September 2014.

Just by entering into orbit, MOM had succeeded. After all, the mission was envisioned to be a “technology demonstrator” — to test “capability [of the craft] to survive and perform Earth-bound manoeuvres; a cruise phase of 300 days of travel; Mars orbit insertion/capture and on-orbit phase around Mars,” as well as technology pertaining to “deep space communication, navigation, mission planning and management,” S Arunan, director of Mars Orbiter Mission, wrote in From Fishing Hamlet to Red Planet.

But the mission also achieved its many scientific objectives, studying the martian surface and atmosphere, as well as other planetary and solar phenomena. It also took some of the most stunning pictures of the Red Planet till date.

The Mars Orbiter Mission caught the imagination of the nation — and the world. ISRO was hailed world over, from the United States to China, for its monumental effort. But, as S Arunan put it in 2015: “MOM is a precursor to more complex and ambitious interplanetary missions of ISRO.” ISRO is planning to launch Mangalyaan-2 next year.