The Indian Space Research Organisation (ISRO) has achieved a significant milestone, with its Chandrayaan-2 orbiter capturing the first-ever direct observation of a Coronal Mass Ejection’s (CME) effect on the Moon’s exosphere. This historic accomplishment marks a first for any space agency worldwide and enhances our understanding of the dynamic interaction between the Sun and the Moon.
Utilizing the Chandra Atmospheric Composition Explorer-2 (CHACE-2) instrument, Chandrayaan-2 monitored a series of powerful CMEs that struck the Moon on May 10, 2024. These solar eruptions, which are massive releases of plasma and magnetic fields from the Sun’s corona, caused a significant increase in the pressure of the Moon’s exosphere. ISRO scientists observed a more than tenfold increase in the number density of neutral atoms and molecules in the lunar exosphere, providing the first direct observational evidence for such phenomena.
The Moon’s exosphere is highly sensitive to solar radiation and solar wind due to its lack of a global magnetic field. The CME event significantly enhanced the release of atoms from the lunar surface, temporarily altering the atmospheric conditions. These findings are vital for understanding lunar space weather and will be instrumental in planning future crewed missions and establishing sustainable habitats on the Moon. The research was published in Geophysical Research Letters, further cementing India’s leadership in space exploration.