Possible Quake On Moon: Chandrayaan-3 Detects 'Natural' Lunar Seismic Event

ISRO (Indian Space Research Organisation) has reported significant developments in its Chandrayaan-3 mission. The Instrument for the Lunar Seismic Activity (ILSA) payload aboard the Vikram lander has captured a notable seismic event on August 26. This marks a crucial milestone as ILSA, built using cutting-edge micro electro mechanical systems (MEMS) technology, becomes the first instrument of its kind on the lunar surface. The event, believed to be of natural origin, is currently under investigation to determine its source.

Unique Design and Development

The Instrument for the Lunar Seismic Activity, conceptualized and realized by the Laboratory for Electro Optics System (LEOS) in Bengaluru, incorporates a cluster of six highly sensitive accelerometers. These accelerometers employ indigenous Silicon Micromachining fabrication techniques. The core sensing element features a spring-mass system complemented by comb-structured electrodes. Vibrations from external sources cause the spring to deflect, resulting in a change in capacitance that is then converted into voltage.

Understanding the Objectives

Vikram Lander's ILSA holds a primary mission objective: to record ground vibrations generated by a variety of sources, including natural quakes, impacts, and artificial events, during the Chandrayaan-3 mission. A recent figure posted by ISRO on social media platform X showcases the vibrations captured during the rover's navigation on August 25. Notably, another event, possibly of natural origin, was recorded on August 26, the details of which are currently being probed by ISRO's scientific teams.

Unprecedented Plasma Measurements

In a separate achievement, ISRO reported that the radio anatomy of moon-bound hypersensitive ionosphere and atmosphere-Langmuir probe (RAMBHA-LP) payload, also onboard the Chandrayaan-3 lander, has achieved a groundbreaking feat. RAMBHA-LP has conducted the first-ever measurements of the near-surface lunar plasma environment over the south polar region. Preliminary assessments indicate that the plasma density near the lunar surface is relatively sparse.

The measurements garnered by RAMBHA-LP hold promising implications for various aspects of lunar exploration. The data could potentially aid in reducing noise interference caused by lunar plasma in radio-wave communication systems. Moreover, the insights gained could contribute to the optimization of designs for upcoming lunar missions, enhancing their performance and efficiency. The development of the RAMBHA-LP payload is spearheaded by SPL/VSSC (Space Physics Laboratory/Vikram Sarabhai Space Centre) in Thiruvananthapuram.

Additional Payload Insights

ISRO further disclosed noteworthy findings from the Chandrayaan-3 mission. The alpha particle X-ray spectroscope (APXS), situated aboard the rover "Pragyan," has detected the presence of sulphur among other minor elements. This follows earlier confirmation by the laser-induced breakdown spectroscope (LIBS) instrument on Pragyan, revealing the existence of sulphur—a valuable resource used in applications ranging from car batteries to fertilizers.

Lunar Challenges Ahead

As the Chandrayaan-3 mission progresses, it faces impending challenges. With approximately half of its expected operational lifespan completed, the mission is approaching lunar night, when temperatures could plummet as low as -200 degrees Celsius. The Vikram Lander and Pragyan Rover are not equipped to endure such extreme cold temperatures, posing unique obstacles for the continued success of the mission.