Vikram lander records natural event on lunar surface, says ISRO

The Instrument of Lunar Seismic Activity (ILSA) payload on Chandrayaan-3's lander module Vikram recorded a natural event that occurred on the lunar surface on August 26, the source of which is still under investigation, Indian Space Research Organisation (ISRO) said on Thursday.

"The Instrument for Lunar Seismic Activity (ILSA) payload on the Chandrayaan 3 Lander is the first instance of a Micro Electro Mechanical Systems (MEMS) technology-based instrument on the moon. It has recorded the vibrations occurring due to the movements of Rover and other payloads," ISRO said.

Taking to social media platform X, the space agency said, "Additionally, it has recorded an event, appearing to be a natural one, on August 26, 2023. The source of this event is under investigation."

ILSA comprises a cluster of six high-sensitivity accelerometers, which are indigenously fabricated using the Silicon Micromachining process. The core sensing element 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.

ILSA's primary objective is to measure ground vibrations generated by natural quakes, impacts, and artificial events. The vibrations recorded during the rover's navigation on August 25, 2023, are depicted in the figure. Additionally, an event, seemingly natural, recorded on August 26, 2023, is also shown. The source of this event is currently under investigation.

The ILSA payload was designed and realised at LEOS, Bangalore, with the support of private industries. The deployment mechanism for placing ILSA on the lunar surface was developed by URSC, Bengaluru.

India took a giant leap on August 23, as the Chandrayaan-3 lander module successfully touched down on the moon’s South Pole, making it the first country to have achieved the historic feat. The country became only the fourth — after the US, China, and Russia – to have successfully placed a lander on the moon.

Prime Minister Narendra Modi later announced that the touchdown spot of the Vikram lander on the lunar surface would from now onwards be known as the ‘Shiv Shakti’ point.