Identification and preliminary characterisation of signals recorded by instrument for lunar seismic activity at the Chandrayaan 3 landing site

The science objective of the Instrument for Lunar Seismic Activity (ILSA) is to study the seismicity at the landing site of the Indian lunar mission, the Chandrayaan 3. It also aimed at demonstrating the capability of devices based on silicon micromachining technology to survive and operate in planetary missions and environments. The Chandrayaan 3 mission had a lander and a rover together carrying five different scientific instruments. ILSA was placed on the lunar surface and had six accelerometers in it. It was operated during the lunar day from 24 August 2023 to 4 September 2023. This paper presents the summary of observations made on 190 h of data recorded by ILSA. We have identified more than 250 distinct signals of which about 200 signals are correlated to known activities involving the physical movements of the rover or the operation of science instruments. This paper presents our approach in the preliminary characterisation and cataloguing of the events based on their temporal properties and spectral contents. It will also act a guide for the future researchers to search, identify and analyse the records made by ILSA.