Anniversary: Quo Vadis, Chandrayaan 2?

An artist’s impression of Chandrayaan 2 cruising above the Moon. The Vikram lander is still connected to the orbiter at this point. Image: ISRO.

The Chandrayaan 2 mission entered lunar orbit on August 20, 2019. On September 2, after a series of manoeuvres, the Vikram lander, with the Pragyan rover in its belly, separated from the orbiter. On September 3, Vikram dropped to a lower orbit in anticipation of its landing on September 7. Then, at 01:38:03 on September 7, Vikram began its ’15 minutes of terror’ journey to the lunar surface, to land on a high plain between the craters Manzinus C and Simpelius N.

It never got there. Instead, the lander deviated from its planned trajectory about 2.1 km over the lunar surface. When it was 330 m above, all communications ceased even as its velocity was a whopping 58 m/s – a lot higher than the planned 2 m/s required at touchdown. Vikram had crashed.

A year after the successful lunar orbit insertion, there are no celebrations of this major milestone in India’s interplanetary missions programme. The only acknowledgement of this event is a document on the Indian Space Research Organisation (ISRO) website that lists results from one year of the orbiter’s operation. There are stunning images from its Terrain Mapping Camera and the Orbiter High Resolution Camera (OHRC), and results from the Large Area Soft X-ray Spectrometer, the Solar X-ray Monitor, the Dual Frequency Synthetic Aperture Radar and other sensors.

Interestingly, OHRC is the highest resolution camera in lunar orbit, across all satellites and probes operated by all countries. With a resolution of 30 cm, it imaged the targeted landing area between the craters Manzinus C and Simpelius N in March 2020. However, it hasn’t attempted to image the area where Vikram is thought to have crashed, some 600 m short of the landing site.

An amateur space aficionado named Shanmuga Subramanian form Chennai had located a part of Vikram using images from the NASA Lunar Reconnaissance Orbiter, which has a much lower resolution. NASA confirmed his submission on December 3, 2019 – while ISRO remains loath to confirm the finding using OHRC or even based on what data it has using other instruments.

Also read: Explainer: Why Did the Chandrayaan 2 Lander Take so Long to Find?

Indeed, the muted silence on science findings from the orbiter data is baffling. Barring the 14-page summary on the ISRO website, there is precious little on view. Browsing through the journal Current Science, ISRO’s preferred journal in which to publish science results, there are articles on the sensors in the January and February 2020 issues but nothing more. The websites of Space Applications Centre and Physical Research Laboratory, the two main sources of the Chandrayaan 2 mission payloads, have absolutely nothing on the data from one year of the orbiter orbiting the Moon.

There is also no ‘announcement of opportunity’ for Chandrayaan 2 data visible on the ISRO website. Worse yet, the data does not seem to be available to any third party who might be interested in it.

Though ISRO chairman K. Sivan had stated that Chandrayaan 2 had been 95% successful, it would seem ISRO wants to dismiss Chandrayaan 2 as a bad dream. It is difficult to understand this neglect because, despite the loss, getting that close to the Moon’s surface was an amazing achievement. The build up to the launch in the press, the outreach among students, and the live media coverage were excellent steps that aroused interest worldwide. Many space experts and scientists even sympathised with the loss. Space is unforgiving but exploring it is a great adventure all the same. There is no shame in failures. But in ISRO, Chandrayaan 2’s reputation seems to be one of failure.

Perhaps we could have anticipated this state of affairs: what followed the loss of Vikram and Pragyan was nothing but a theatre of the absurd. The mission control team kept attempting to reestablish communications with the lander even though independent observations from other countries indicated that the cessation of communications pointed to a crash. On September 10, 2019, ISRO issued a terse statement: “Vikram lander has been located by the orbiter of Chandrayaan 2, but no communication with it yet. All possible efforts are being made to establish communication with lander.”

The organisation set up a failure review committee on September 19, which pointed to a software glitch and then… silence. To this day, a year after the event, the findings of the committee have not been made public. Subramanian was snubbed by ISRO even though NASA confirmed his findings, which only showed ISRO in bad light.

Also read: If ‘Chandrayaan 2 Was a 90-95% Success’ Is the Answer, What’s the Question?

But Subramanian persists. On Twitter posts, on August 1 this year, he claimed it is possible all was not lost. While the lander was damaged in the hard landing, he said some images suggest the rover possibly managed to survive and roll out for a few metres. It is possible that the series of commands sent out in a desperate bid to revive the lander might have actually been received and acted upon by the remnants of the lander and relayed to the rover. However, there is no way to confirm this hypothesis as the lander’s signals haven’t been received at ISRO’s control station in Byalalu.

Is ISRO not interested in knowing what has happened? Can it not use the OHRC to prove or disprove Subramanian’s observations? Or perhaps they do know but – or and – they will not tell. As I said, baffling!