Nearly three months after ISRO’s Chandrayaan-2 made a “hard landing” on the lunar surface, NASA tweeted that it had spotted the remains of the Vikram lander and credited an unexpected source for the discovery — a software programmer in Chennai.

How lander was found?

Shanmuga Subramanian (33) used a basic image viewer on his personal laptop to find lander.

After the early hours of September 7, when ISRO said that the lander had made “a hard landing”, Subramanian started trying to trace it from photographs available in the public domain, primarily NASA’s website.

What he finally found was one of the many parts of the lander scattered across an area of about 4 km.

The Lunar Reconnaissance Orbiter (LRO) Camera of NASA frequently takes photos of the moon’s surface, almost every month. After the ISRO mission failed, I downloaded pictures clicked by LROC before and after the crash and studied them, zooming in pixel by pixel on each photograph,” he said.

I was focusing on a particular location where the lander was believed to have crashed. While comparing old and new pictures, I noticed a single dot, the only difference I could trace among the many. Some opined that it may be dust. But I was certain. There were specifics… for instance, the difference in light reflections. Reflections from craters and stones are different to those from man-made objects. A man-made object will have a reflection around it. This is what made me realise that I was correct,” said Subramanian.  “I tweeted to ISRO and NASA and later sent an email on October 18. Finally, today morning, they (NASA) sent a confirmation mail,” he said.

Source: The Indian Express

Relevant for GS Prelims & Mains Paper III; Science & Technology