Sun Oct 19 00:57:53 UTC 2025: Summary:
India’s Chandrayaan-2 lunar orbiter has achieved a groundbreaking first: observing the effects of a solar Coronal Mass Ejection (CME) on the Moon. The orbiter’s CHACE-2 payload detected a significant increase in the total pressure of the Moon’s thin atmosphere (exosphere) when a CME hit on May 10, 2024. This confirms theoretical models and highlights the challenges of establishing lunar bases, which need to be designed to withstand such extreme space weather events. The observation provides valuable insight into understanding the lunar exosphere and the impact of space weather on the Moon.
News Article:
Indian Orbiter Makes Landmark Observation of Solar Storm Impacting the Moon
Bengaluru, October 19, 2025: India’s Chandrayaan-2 mission continues to yield groundbreaking scientific discoveries, even years after its launch. The lunar orbiter, launched in 2019, has made the first-ever observation of the direct effects of a solar Coronal Mass Ejection (CME) on the Moon, according to the Indian Space Research Organisation (ISRO).
The Chandra’s Atmospheric Composition Explorer-2 (CHACE-2) payload, carried by the orbiter, recorded a significant increase in the total pressure of the Moon’s dayside exosphere – its extremely thin atmosphere – on May 10, 2024, when a series of powerful CMEs erupted from the Sun.
“The total number density derived from these observations showed an increase by more than an order of magnitude,” ISRO stated. “This increase is consistent with earlier theoretical models, but CHACE-2 onboard Chandrayaan-2 has observed such an effect for the first time.”
According to ISRO, the solar storm enhanced the process of “knocking off” atoms from the lunar surface, releasing them into the exosphere and resulting in the observed pressure surge.
The observation provides valuable insight into the lunar exosphere and the effects of space weather on the Moon. Furthermore, ISRO emphasizes the implications for future lunar missions, particularly the establishment of lunar bases.
“This observation also indicates the challenges of building scientific bases on the Moon. Lunar base architects need to account for such extreme events, which would temporarily alter the lunar environment, before the effects subside,” ISRO noted.
Chandrayaan-2, launched on July 22, 2019, carried eight scientific payloads. While the mission’s Vikram lander unfortunately failed to achieve a soft landing, the orbiter continues to operate successfully, providing invaluable data and pushing the boundaries of our understanding of the Moon. This latest discovery reinforces the importance of continued lunar exploration and the challenges of building a sustainable presence on Earth’s nearest celestial neighbor.
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