As ISRO scientists continue the uphill task of establishing contact with Chandrayaan-2’s Vikram Lander, which is lying in a tilted position of Moon’s surface, latest reports highlight the exact moment when the Vikram Lander went silence. A report by the Indian Express says that giant screens at the ISRO Command Centre shows that Vikram Lander went silent at 335 metres from Moon. The problem in the final descent came during what is known as final breaking phase. Stating the sequence of events, the ISRO said that “normal performance (of Vikram) was observed up to an altitude of 2.1 km”, and “subsequently, communication from Lander to the ground stations was lost”.
The Indian Express report said that the frozen giant screens at the ISRO Command Centres showed that precise moment of radio silence – 335 metres or 0.335 km, a minute distance from the surface of Moon. Now the scientists believe that the issue with the descent was the increased velocity of the Vikram lander. The report says that Vikram Lander didn’t lose the velocity as per the plan.
Apart from decoding this mystery, the ISRO has a strict deadline for reviving any contact with Vikram lander. According to the Indian Express report, the only chance ISRO has is till September 21. This is because, after this date, the Moon will enter its lunar night. For those who don’t know, lunar days and nights are equivalent to 14 Earth days. Temperatures could drop to as low as -200°C.
Vikram, with rover 'Pragyan' housed inside it, hit the lunar surface after communication with the ground-stations was lost during its final descent, just 2.1 km above the lunar surface, in the early hours of Saturday.
"We are making all-out efforts to see whether communication can be re-established with the lander," another ISRO official told PTI. "An ISRO team is the on the job at ISROTelemetry, Tracking and Command Network (ISTRAC)."
The mission life of the lander and rover is one Lunar day, which is equal to 14 earth days. The chances of getting Vikram back are dim but not totally bleak. The good news for ISRO is that the lander is intact even after a hard landing.
"It had a hard-landing very close to the planned (touch-down) site as per the images sent by the on-board camera of the orbiter. The lander is there as a single piece, not broken into pieces. It's in a tilted position," an ISRO official associated with the mission claimed on Monday.