ISRO Selects South Polar Site for Chandrayaan-4 Lander

The Indian Space Research Organisation (ISRO) has identified a precise landing site on the Moon for its ambitious Chandrayaan-4 mission, even as the mission itself is scheduled for launch around 2028. The announcement signals a critical early milestone for India’s first lunar sample-return endeavour, approved by the Union government and described as the country’s most complex lunar mission to date.

Focus on the Moon’s South Polar Region

ISRO has zeroed in on the Mons Mouton region near the Moon’s south pole, an area of high scientific interest due to its terrain characteristics and proximity to permanently shadowed regions. Scientists evaluated four candidate sites within Mons Mouton—designated MM-1, MM-3, MM-4 and MM-5—using extensive remote sensing data. After detailed analysis, site MM-4 was selected as the most suitable location for the Chandrayaan-4 lander.

Terrain Analysis and Safety Parameters

The selection was based on high-resolution multi-view imagery captured by the Orbiter High Resolution Camera. ISRO officials noted that a one-kilometre by one-kilometre area around MM-4 showed the lowest hazard percentage among the shortlisted sites. The region has a mean slope of about five degrees and an average elevation of 5,334 metres, making it favourable for a controlled soft landing. Crucially, MM-4 also offers the highest number of hazard-free grids measuring 24 metres by 24 metres, which is vital for landing accuracy and safety.

Mission Architecture and Landing Strategy

Chandrayaan-4 is designed as a multi-module mission comprising a Propulsion Module, Descender Module, Ascender Module, Transfer Module and a Re-entry Module. The Descender and Ascender Modules will form a combined stack that will soft-land at the designated site. ISRO has emphasised that precise navigation, guidance and control during descent, coupled with careful landing site selection, are central to ensuring mission success.

Important Facts for Exams

• Chandrayaan-4 will be India’s first lunar sample-return mission.
• The selected landing site MM-4 lies in the Mons Mouton region near the Moon’s south pole.
• Orbiter High Resolution Camera data was used to assess landing hazards and terrain slopes.
• The mission involves multiple modules, including a dedicated re-entry system for lunar samples.

Timeline and Strategic Significance

According to ISRO Chairman V Narayanan, the agency is targeting 2028 for the Chandrayaan-4 launch. Early identification of the landing site allows engineers to refine descent trajectories and mission design well in advance. The mission is expected to significantly enhance India’s standing in planetary exploration and contribute valuable scientific data on the Moon’s south polar environment.