Chandrayaan-1 may have just detected oldest impact basin on moon
Worth reading — 1 past UPSC question on this theme (Mains GS-3 2016).
2-minute summary
Planetary scientists from the Physical Research Laboratory (PRL), Ahmedabad, have detected a hidden, ancient impact crater on the Moon called the Australe Basin. Analyzing archival data from India's 2008 Chandrayaan-1 mission, specifically from NASA's Moon Mineralogy Mapper (M3) payload, the team identified this heavily eroded basin in the Moon's southeastern hemisphere. The study suggests the Australe Basin could be older than the South Pole-Aitken Basin (previously considered the oldest at over 4 billion years). Unlike typical high-calcium lunar basalts, the Australe Basin features unique low-calcium, high-magnesium mineralogy and is characterized by 248 small basalt ponds arranged in a circular pattern. This discovery provides a vital geological framework for future lunar exploration, including India's upcoming Chandrayaan-4 sample return mission and NASA's Artemis program, by helping scientists understand how ancient regolith evolved and migrated across the lunar South Pole.
Why it's in the news
Researchers at the Physical Research Laboratory (PRL) have published a study in The Planetary Science Journal confirming the detection of the Australe Basin, potentially the oldest impact basin on the Moon, using data from India's Chandrayaan-1 mission.
Facts to remember
- Planetary scientists from the Physical Research Laboratory (PRL), Ahmedabad, detected a hidden ancient lunar impact crater called the Australe Basin using archival data from the 2008 Chandrayaan-1 mission.
- The mineralogical data for the discovery was gathered using NASA's Moon Mineralogy Mapper (M3) payload aboard Chandrayaan-1.
- Unlike typical high-calcium lunar basalts, the Australe Basin features unique low-calcium, high-magnesium mineralogy characterized by 248 small basalt ponds in a circular pattern.
- Chandrayaan-1 was launched in 2008 as India's first lunar probe, carrying 11 scientific payloads including 5 Indian and 6 international instruments.
Background and context
Launched in 2008, Chandrayaan-1 was India's first lunar probe, carrying 11 scientific payloads (including 5 Indian and 6 international instruments). Among these was NASA's Moon Mineralogy Mapper (M3), an imaging spectrometer operating in the 405 to 3000 nanometer range, famous for confirming water molecules on the Moon. Impact basins are large craters (hundreds of kilometers wide) formed by ancient asteroid or meteorite impacts. Of the estimated 300 impact basins on the Moon, only 74 have been formally detected due to billions of years of erosion and volcanic resurfacing. Until now, the South Pole-Aitken (SPA) Basin, dating back over 4 billion years, was considered the oldest and largest. The discovery of the Australe Basin challenges this timeline and enhances our understanding of early solar system bombardment.
International organisations
- National Aeronautics and Space Administration (NASA) — Collaborated on India's Chandrayaan-1 mission by providing the Moon Mineralogy Mapper (M3) payload, which was instrumental in gathering the mineralogical data used in this discovery.
Previous UPSC questions on this theme
- Mains GS-3 2016 — Discuss India's achievements in the field of Space Science and Technology. How the application of this technology has helped India in its socio-economic development?
Mains practice: How does the study of lunar geology and ancient impact basins help in understanding the early history of the solar system? Discuss in the light of recent discoveries made using Chandrayaan-1 data.
The study of lunar geology, particularly its ancient impact basins, serves as a pristine window into the early history of the solar system. Unlike Earth, which undergoes continuous resurfacing due to plate tectonics, weathering, and liquid water, the Moon lacks these active geological processes. Consequently, its surface preserves a record of cosmic events dating back over four billion years.
Recent discoveries using archival data from India's Chandrayaan-1 mission highlight this scientific value:
• **Dating the Early Solar System**: The detection of the Australe Basin by PRL scientists, potentially predating the South Pole-Aitken (SPA) Basin, helps refine the timeline of the 'Late Heavy Bombardment'—a period of intense asteroid impacts that affected the inner solar system, including early Earth.
• **Mantle and Volcanic Evolution**: The unique mineralogy of the Australe Basin—characterized by low-calcium, magnesium-rich basalts and 248 small circular basalt ponds—reveals localized volcanic processes and mantle compositions distinct from the vast, smooth lava plains (maria) observed elsewhere.
• **Regolith Dynamics and Transport**: Understanding how impact events excavated and distributed magnesium-bearing materials across the lunar surface (such as deposits found near Chandrayaan-3's Shiv Shakti landing site) helps scientists map the evolution of lunar soil (regolith) over billions of years.
• **Guiding Future Exploration**: Mapping these ancient basins provides a vital geological framework for landing site selection and sample analysis for upcoming missions, such as India's Chandrayaan-4 sample return mission and NASA's Artemis program.
In conclusion, analyzing the Moon's oldest impact structures allows scientists to reconstruct the dynamic environment of the early solar system, demonstrating how India's early space assets continue to yield high-value scientific dividends.
Prelims practice questions
Q1. With reference to the recently discovered 'Australe Basin' on the Moon, consider the following statements: 1. It was detected using mineralogical data from India's Chandrayaan-1 mission. 2. Unlike typical lunar basalts, the basalts in this basin are characterized by low calcium and high magnesium content. 3. It is characterized by a single, massive and smooth hardened lava surface. Which of the statements given above is/are correct?
- 1 and 2 only
- 2 and 3 only
- 1 and 3 only
- 1, 2 and 3
Answer: A. Statements 1 and 2 are correct. Statement 3 is incorrect because the Australe Basin is characterized by a unique province of 248 small basalt ponds arranged in a circular pattern, unlike other known impact basins that feature vast, smooth hardened lava surfaces.
Q2. The 'Moon Mineralogy Mapper (M3)', an imaging spectrometer that helped map the lunar surface's mineralogy, was a payload on Chandrayaan-1 contributed by which space agency?
- Roscosmos
- European Space Agency (ESA)
- Japan Aerospace Exploration Agency (JAXA)
- National Aeronautics and Space Administration (NASA)
Answer: D. The Moon Mineralogy Mapper (M3) was an imaging spectrometer designed and contributed by NASA as one of the foreign payloads onboard India's Chandrayaan-1 mission.
Q3. Consider the following statements regarding lunar geology and research institutions: 1. The South Pole-Aitken Basin was previously considered the oldest and largest known impact basin on the Moon. 2. The Physical Research Laboratory (PRL), which analyzed the Chandrayaan-1 data, is an autonomous unit under the Department of Space. Which of the statements given above is/are correct?
- 1 only
- 2 only
- Both 1 and 2
- Neither 1 nor 2
Answer: C. Both statements are correct. The South Pole-Aitken Basin (formed over 4 billion years ago) was the oldest known impact basin. The Physical Research Laboratory (PRL) in Ahmedabad is an autonomous unit operating under the Department of Space, Government of India.
Revision flashcards
- Which instrument on Chandrayaan-1 was used to detect the mineralogy of the Australe Basin? NASA's Moon Mineralogy Mapper (M3), an imaging spectrometer operating between the 405 and 3000 nanometer wavelength range.
- How does the mineral composition of the Australe Basin differ from most other lunar basalts? It has relatively lower calcium and higher magnesium content, whereas the majority of lunar basalts are high in calcium.
- What unique geological layout characterizes the Australe Basin instead of smooth lava plains? A province of 248 small basalt ponds arranged in a circular pattern.
- Where is the Physical Research Laboratory (PRL) located, and under which department does it operate? It is located in Ahmedabad and operates as an autonomous unit under the Department of Space, Government of India.
- Why is the discovery of the Australe Basin significant for India's future Chandrayaan-4 mission? It provides crucial mineralogical and geological context for selecting landing sites and analyzing returned samples from the lunar South Pole region.