Why in news?

A study by scientists of ISRO has estimated the age of the Chandrayaan-3 landing site on the Moon to be 3.7 billion years.

This period aligns with the time when primitive microbial life first appeared on Earth.

What’s in today’s article?

• Regional Geography of the Chandrayaan-3 Landing Site
• ISRO Scientists Uncover Age and Evolution of Chandrayaan-3 Landing Site
• Significance of the study: Understanding the Moon’s Violent History

Regional Geography of the Chandrayaan-3 Landing Site

• In August 2023, India became the first country to achieve a soft landing on the Moon’s south pole.
• The landing site is now known as Shiv Shakti Point. This Point is enclosed by multiple large craters:
  • Manzinus Crater (96 km diameter, ~3.9 billion years old) to the north
  • Boguslawsky Crater (95 km diameter, ~4 billion years old) to the southeast
  • Schomberger Crater (86 km diameter, ~3.7 billion years old) to the south
• Manzinus and Boguslawsky have flat floors and subdued walls, while Schomberger stands out due to its steep crater walls, central peak, raised rim, and well-preserved ejecta blanket.

ISRO Scientists Uncover Age and Evolution of Chandrayaan-3 Landing Site

• The landing site, now known as Shiv Shakti Point, has been under detailed study by ISRO’s Physical Research Laboratory (PRL) scientists using data from the Pragyan rover and Vikram lander.
• This mapping effort provides vital geological context for lunar exploration and deepens our knowledge of the Moon’s evolution and impact history.
• The findings have been published in the journal Advances in Space Research.
• Study technique - Advanced Imaging and Terrain Analysis
  • PRL scientists used high-end imaging techniques, including the Lunar Reconnaissance Orbiter’s wide-angle and terrain cameras, to analyze craters and rock distributions near the landing site.
  • The Pragyan rover identified multiple rock fragments (over 1 cm in size) and secondary crater chains, helping researchers trace the origins of lunar materials in the area.
• Identifying the Source of Lunar Rocks
  • The PRL team analyzed rock distributions around the landing area and the region navigated by Pragyan rover. They found that:
    • A higher rock concentration exists near a fresh crater (14 km south of the landing site), identified by continuous ejecta and a sharp rim.
    • This fresh crater material showed less space weathering compared to its surroundings.
• Key highlights of the study
  • Estimating the Age of the Region
    • By studying 25 craters (500-1,150 meters in diameter) in the low-relief smooth plains, scientists estimated the site's age to be 3.7 billion years (Ga).
  • Lunar Surface Evolution
    • The region has undergone continuous micro-meteorite bombardments and extreme thermal fluctuations, leading to the gradual breakdown of exposed rocks into lunar regolith over millions of years.
  • Formation of the Local Terrain
    • Based on morphological studies, scientists concluded that the landing site’s terrain primarily consists of ejecta from two secondary craters—Manzinus and Boguslawsky—shaping the region over time.

Significance of the study: Understanding the Moon’s Violent History

• Unlike Earth, the Moon lacks an atmosphere, making it vulnerable to constant asteroid impacts.
• Just counting the impact craters on the Moon helps determine the age of the landscape.
• Chandrayaan 3 landed in a heavily cratered region. The geological map allows scientists with the context necessary to interpret the data captured by the mission.
• It improves the scientific understanding of the geological history of the highlands around the south pole of the Moon.