Chandrayaan-2 Observes Lunar Exosphere Changes

India’s Chandrayaan-2 mission has achieved a remarkable milestone by making the first-ever observation of the sun’s coronal mass ejection (CME) effects on the moon. This discovery, made by the Chandra’s Atmospheric Composition Explorer-2 (CHACE-2) payload onboard the lunar orbiter, provides valuable insights into lunar and space weather phenomena.

Observation of Coronal Mass Ejection

The CHACE-2 payload aboard Chandrayaan-2 observed the impact of a coronal mass ejection on the moon’s dayside exosphere, a very thin atmosphere. The data revealed a notable increase in the total pressure of the lunar exosphere when the CME struck the moon. The total number density, or the number of neutral atoms or molecules per unit volume, increased by more than an order of magnitude, confirming earlier theoretical models. This marked the first time such an effect was observed directly.

Rare Celestial Event

This observation occurred during a rare celestial event on 10 May 2024, when a series of CMEs were emitted by the sun. The increased solar mass impacted the moon, enhancing the process of liberating atoms from the lunar surface into the exosphere, resulting in heightened pressure. This phenomenon provides a unique opportunity to study the interaction between solar activity and the lunar environment.

Implications for Lunar Exploration

The findings from Chandrayaan-2 have remarkable implications for future lunar exploration and the establishment of scientific bases on the moon. Understanding the effects of CMEs on the lunar environment is crucial for designing infrastructure that can withstand such extreme events. This knowledge is essential for planning sustainable human and robotic activities on the lunar surface.

Chandrayaan-2 Mission

Launched on 22 July 2019 using the GSLV-MkIII-M1 rocket, Chandrayaan-2 was equipped with eight scientific payloads. Despite the loss of communication with the Vikram lander during its attempted soft landing, the mission’s orbiter continues to provide valuable scientific data. The mission affirms India’s growing capabilities in space exploration and its contributions to global scientific knowledge.