Chandrayaan-1 May Have Just Detected Oldest Impact Basin on Moon: Researchers

Key Highlights & Summary 

• Discovery of Ancient Impact Basin: Researchers from the Physical Research Laboratory (PRL), Ahmedabad, identified the Australe Basin on the Moon\'s southeastern hemisphere using Chandrayaan-1 mineralogical data, which could predated the oldest known lunar impact basins. 

• Potential Record-Breaking Age: PRL scientists indicate the Australe Basin might be older than the South Pole-Aitken Basin, which was formed over 4 billion years ago and was previously considered the Moon\'s oldest and largest known impact structure. 

• Unique Mineralogical Composition: Unlike typical lunar basalts high in calcium, the volcanism within the Australe Basin features lower calcium and higher magnesium concentrations, along with 248 small basalt ponds arranged in a circular pattern. 

• Utilization of NASA’s M3 Instrument: The basin\'s mineralogy was confirmed using data from the Moon Mineralogy Mapper (M3), an imaging spectrometer onboard Chandrayaan-1 operating in the 405 to 3000 nanometer wavelength range. 

• Link to Chandrayaan-3 Shiv Shakti Point: Findings show that magnesium-rich material excavated from ancient south polar impacts like Australe may have transported regolith to the Chandrayaan-3 landing site, located nearly 350 km away. 

• Significance for Future Missions: The findings provide a geological framework for future lunar exploration and sample return missions, including NASA’s proposed Moon Base and ISRO’s Chandrayaan-4 mission. 

Essential Definitions 

• Impact Basin: A large, complex depression on a planetary surface created by hypervelocity collisions with massive extraterrestrial bodies like asteroids or meteorites, often spanning hundreds of kilometers in diameter.  

• Moon Mineralogy Mapper (M3): An imaging spectrometer payload provided by NASA aboard India\'s Chandrayaan-1 spacecraft, designed to map the mineral composition of the lunar surface. 

• Regolith: The loose, fragmented layer of heterogeneous unconsolidated rock and dust that covers solid bedrock on planetary bodies like the Moon. 

Legal and Constitutional Framework

• Outer Space Treaty, 1967: Establishes that outer space and celestial bodies like the Moon shall be free for exploration and use by all states for peaceful purposes and non-appropriation. 

• Artemis Accords: A non-binding multilateral agreement establishing principles for cooperation in civil exploration and peaceful use of the Moon, Mars, and other celestial bodies, to which India is a signatory.

• Article 51A(h) of the Indian Constitution: Directs every Indian citizen to develop a scientific temper, humanism, and the spirit of inquiry and reform.

 Conclusion The identification of the ancient Australe Basin highlights the enduring scientific value of India\'s early planetary exploration missions. By uncovering key insights into lunar volcanism and regolith evolution, these findings enhance global planetary science and aid future sample-return missions under India\'s expanding space exploration roadmap.

 UPSC Relevance

 • GS Paper III: Science and Technology (Achievements of Indians in science & technology, space technology developments, awareness in space exploration, ISRO missions like Chandrayaan series, and international technological collaboration). 

• GS Paper I: Physical Geography (General concepts of planetary evolution, geomorphology, and surface characteristics of celestial bodies).