Moon Lander Records "Event, Appears Natural, Under Investigation": ISRO

The Instrument of Lunar Seismic Activity payload on Chandrayaan-3's Lander Vikram recorded a natural event that occurred on the Moon's surface on August 26, the source of which is still under investigation, the space agency said.

The Instrument for Lunar Seismic Activity's (ILSA) primary objective is to measure ground vibrations generated by natural quakes, impacts, and artificial events. 

The ILSA also recorded vibrations of the rover's movement on the Moon's surface on August 25. The space agency shared an acceleration-time graph that recorded the ILSA's response to the rover's movement. 

The ILSA comprises a cluster of six highly sensitive accelerometers; A device that measures the vibration or acceleration motion of a structure. 

The vibrations, as seen in the graph, show the rover's movement phase. The movement of the payloads on the lander was also recorded.

The ILSA is the first instance of a Micro Electro Mechanical Systems technology-based instrument on the moon. 

Micro-electromechanical systems (MEMS) is a process technology used to create tiny integrated devices or systems that combine mechanical and electrical components. 

The core sensing element of the ILSA consists of a spring-mass system with comb-structured electrodes. External vibrations lead to a deflection of the spring, resulting in a change in capacitance which is converted into voltage.

In its first-ever on-site measurements of the south polar region of the Moon, the Pragyaan rover confirmed the presence of sulphur in the region. 

The ISRO said the in-situ measurements confirmed the presence of sulphur in the region “unambiguously”, which was not feasible using the instruments onboard the orbiters.

The presence of oxygen, calcium and iron has also been detected and the hunt for hydrogen is underway. 

India had created history on August 23 by becoming the first country to achieve a soft landing near the south pole of the moon. It had also joined an elite club of countries - Russia, the US and China - to have successfully landed on the lunar surface.