Eminent space Scientist Tapan Misra, who is presently posted as Advisor at the ISRO headquarters in Bengaluru, views the LRO images of Chandrayaan-2 crash landing site released by NASA as “very interesting”. These have changed many conventional ideas, he had in mind, Misra points out in a facebook post.
According to Misra, the lander with partially burnt fuel must have had a mass of 700-800 kg, similar to that of a sedan car or a small aircraft. And as per ISRO data, it was travelling at a speed of 534 km per hour, speed of a jet aircraft. With this impact like jet crash on lunar regolith, a very fine dust of 0.5 m to 5-6 m thick covering of lunar surface, would have created a great upheaval at the first impact site, spreading around 10 m or more across. Almost like a small crater or dent. In fact the dust or debris could jump up much more than on earth, as lunar gravity is one-sixth of earth. But surprisingly not a single change in dent one can see, except local brightness variation.
Also he expected, the unspent fuel would have got split on lunar surface and must have burnt a while as both fuel and oxidizer were present. This could have left a dark patch on lunar surface. But nothing like this is seen.
Also he expected some debris to be left behind at the first impact site. But he could see none.
Another interesting phenomenon Misra has observed – all the debris tended to get strewn, dominantly along a linear patch. He expected them to be strewn all around, considering randomness in rebounding of broken pieces after the first crash. During first impact at high speed, lander would have got compressed and broken. The stored energy because of compression would have got released next, by throwing away the broken pieces of lander in different arbitrary directions.
Further all spacecraft components and structure elements were black painted. But it appears all the debris identified, are shiny. He thought they should appear dark.