Chandrayaan-2 Detects Evidence of Subsurface Water Ice Near Moon’s South Pole

India’s Chandrayaan-2 mission has provided strong evidence for the presence of buried water ice near the Moon’s south pole, marking a significant advancement in lunar exploration and the search for extraterrestrial resources.

The findings emerged from a detailed study conducted by scientists at Physical Research Laboratory using data from the Dual Frequency Synthetic Aperture Radar (DFSAR) onboard the Chandrayaan-2 orbiter.

About DFSAR

• DFSAR is a microwave imaging instrument onboard Chandrayaan-2.
• It is the first fully-polarimetric Synthetic Aperture Radar (SAR) designed to study the Moon.
• The instrument enables scientists to investigate subsurface features and detect possible water-ice deposits in permanently shadowed lunar regions.

Focus of the Study

The research concentrated on “doubly shadowed craters” located within the Moon’s Permanently Shadowed Regions (PSRs) near the lunar south pole.

These regions:

• Never receive direct sunlight.
• Are shielded from thermal radiation.
• Maintain extremely low temperatures of around 25 Kelvin (-248°C).
• Provide ideal conditions for preserving water ice over billions of years.

Key Findings

Using advanced radar polarimetric analysis, scientists identified radar signatures indicating the possible presence of subsurface water ice beneath the floors of four doubly shadowed craters.

Major Discovery

• One crater measuring 1.1 km in diameter within the larger Faustini crater showed particularly strong evidence of buried ice.
• The evidence was supported by:
  • Radar observations, and
  • Distinctive lobate-rim morphological features.

What is Lobate-Rim Morphology?

A lobate-rim morphology refers to a crater rim having a flow-like or lobed appearance.

Scientists believe this may indicate that:

• The impacting object penetrated subsurface ice.
• The impact caused icy material to flow outward, creating the observed lobed structures.

Source: ISRO