Chandrayaan-2: Vikram in one piece, Pragyan still in it

Chandrayaan-2: Vikram in one piece, Pragyan still in it

Making it tough to re-establish a communication link with Vikram, the Lander now lies in a ‘tilted’ position on the lunar surface. Its orientation is just not right to make contact or restart the stalled Rover roll-out process, said Indian Space Research Organisation (ISRO) scientists. 

On Sunday morning, the Orbiter had located the Lander lying not far away from the predefined landing site. But the images it relayed back to ISRO’s Earth stations showed a definite tilt. It was obvious that the hard-landing at a high velocity had left Vikram with a wrong orientation. 

Losing the communication link just when the Lander was 2.1 km away from the lunar surface early Saturday morning proved critical. ISRO sources had indicated that the end-stage thrusters overperformed, the Lander lost its stability and the central gimbal, which could have restored balance, malfunctioned.

What gives hope for ISRO is that the Lander is still in ‘single piece.’ This would mean the Rover, Pragyan is still inside it. The original plan had Pragyan roll out from Vikram, about three hours and 15 minutes after the soft-landing.  

The space agency is constrained by the Orbiter’s current orbit of 100 km X 100 km in making an accurate analysis of the Lander’s current state. At that height, even with high-definition cameras, it gets extremely tough to judge the extent of damage, explained ISRO sources. 

Since the Lander has solar panels all around and internal batteries, generating power is unlikely to be an issue. But the orientation of the antennas makes all the difference in establishing contact with the Orbiter and the Earth stations. However, ISRO officials said all efforts were on. Sivan had earlier said the attempts will be on for another 13 days. 

Besides the Rover, the Lander’s payloads include the Instrument for Lunar Seismic Activity (ILSA), the Radio Anatomy of Moon Bound Hypersensitive Ionosphere and Atmosphere (RAMBHA), and the Chandra's Surface Thermo-physical Experiment (ChaSTE).

The Orbiter is steady, with an extended life of 7.5 years. This gives ISRO hope that its onboard communication channel can be repeatedly activated to establish a link with the Lander every time its orbit crosses Vikram’s lunar location.