Chandrayaan-2 makes first-ever observations on lunar exosphere: ISRO, Pg14

Key Highlights:

• Chandrayaan-2 made the first-ever observation of the effects of a coronal mass ejection (CME) on the lunar exosphere.
• The observation was made by the Chandra’s Atmospheric Composition Explorer-2 (CHACE-2) payload onboard the Chandrayaan-2 orbiter.
• On May 10, 2024, a series of CMEs hurled by the sun impacted the moon, leading to the observed effects.
• ISRO reported that the observations showed an increase in the total pressure of the dayside lunar exosphere when the CME impacted the moon.

Detailed Insights:

• The total number density in the lunar exosphere increased by more than an order of magnitude due to the CME impact, consistent with theoretical models.
• The CME enhanced the process of atoms being knocked off the lunar surface, increasing their presence in the lunar exosphere.
• This observation provides scientific insight into understanding the lunar exosphere and the effects of space weather on the moon.
• The findings highlight the challenges of building lunar bases, as architects need to consider extreme events like CMEs that can temporarily alter the lunar environment.
• Chandrayaan-2 was launched on July 22, 2019, carrying eight experiment payloads, but the Vikram lander lost communication during its soft landing attempt.

Scientific/Technical Concepts Involved:

• Coronal Mass Ejection (CME): A significant release of plasma and magnetic field from the solar corona.
• Lunar Exosphere: The outermost region of the Moon's atmosphere, characterized by extremely low density.
• Total Number Density: The number of neutral atoms or molecules present in an environment per unit volume.