US space agency acknowledges Shanmuga’s feat in finding elusive lander of Chandrayaan 2
For both USA space agency NASA and India’s ISRO finding Chandrayaan-2’s elusive Vikram lander, which had crash-landed on the lunar surface on September 7 minutes before it was expected to soft land on Moon, was an impossible task until Indian amateur space scientist Shanmuga Subramanian located it by sifting the images from the ISRO’s Moon orbiting spacecraft.
Thirty-three-year-old Subramanian’s effort in locating the site of the debris was acknowledged by NASA.
Madurai-born mechanical engineer and app developer, Subramanian, tweeted,
“NASA has credited me for finding Vikram Lander on Moon’s surface.”
Subramanian, who works as an IT engineer in a Chennai company, said he spent hours going through the images taken by NASA’s Moon orbiting Lunar Reconnaissance Orbiter (LRO), monitoring them on two computers in his “lab”.
Subramanian, who has also keen interest in weather monitoring, said he spent four to six hours a day over the last couple of month closely analysing the images.
“While I was initially not sure where to look, later I found the intended landing site of Vikram Lander and started looking in the adjacent squares for differences,” he said.
The data and information he had collected from multiple sources that the crash landing must have happened to the north of the intended landing site came handy for his probe. This led him to further narrow down the area of search and ultimately pinpoint the spot where the debris from Vikram fell down.
The images were of roughly 1.5 GB size and had a resolution of 1.25 square metre per pixel. There were vertical and horizontal lines with each square marking an area of one square kilometre.
Subramanian zeroed in on the exact spot where the lander ended up after getting out of control and identified the debris of Vikram from the differences in the two pictures provided by the NASA, one before the crash-land and the other after it got disintegrated and fell on the lunar surface.
The images of NASA were taken by its Lunar Reconnaissance Orbiter (LRO) that flew over the area where Vikram was expected to make its landing. “LRO flew over the area on September 17 and NASA released the images through a blog on September 29,” said Subramanian.
The NASA in appreciation of the service rendered by Subramanian tweeted on Tuesday morning about his contribution. “The Lunar Reconnaissance Orbiter Camera team released the first mosaic (acquired Sept. 17) of the site on Sept. 26 and many people have downloaded the mosaic to search for signs of Vikram.
“Subramanian contacted the LRO project with a positive identification of debris. After receiving this tip, the LROC team confirmed the identification by comparing before and after images. When the images for the first mosaic were acquired the impact point was poorly illuminated and thus not easily identifiable. Two subsequent image sequences were acquired on October 14 and 15, and November 11. The LROC team scoured the surrounding area in these new mosaics and found the impact site (70.8810°S, 22.7840°E, 834 m elevation) and associated debris field. The November mosaic had the best pixel scale (0.7 meter) and lighting conditions (72° incidence angle),” the NASA said.
