In a significant breakthrough for India’s lunar ambitions, researchers from the Indian Institute of Technology Kharagpur, working in collaboration with the Physical Research Laboratory, have uncovered new clues about the Moon’s deep interior.
The findings could play a crucial role in shaping the upcoming Chandrayaan-4 mission.
The study focuses on a rare class of iron- and titanium-rich rocks known as ilmenite-bearing cumulates (IBC), believed to have formed around 4.3-4.4 billion years ago when a vast ocean of molten rock covered the Moon. As this magma ocean cooled, dense mineral layers sank deep into the lunar interior, preserving a record of the Moon’s early evolution.
To investigate these ancient materials, the team recreated extreme lunar interior conditions in laboratory experiments, subjecting samples to pressures of up to 3 gigapascals and temperatures exceeding 1,500°C.
These high-pressure experiments revealed how IBC rocks partially melt and interact with the surrounding mantle, producing magmas similar to the titanium-rich basalts observed on the Moon’s surface.
“These results provide an experimental framework to better understand the origin and evolution of lunar samples,” Professor Sujoy Ghosh, one of the lead researchers of the paper, noted, emphasising the importance of such work ahead of future sample-return missions.
The details of the findings have been published in Geochimica et Cosmochimica Acta.
WHAT DID RESEARCHERS UNCOVER ABOUT THE MOON?
One of the key findings is that different melting conditions produce different types of magma.
At higher temperatures, moderately titanium-rich melts can directly form intermediate-Ti basalts. At lower temperatures, however, very high titanium melts first evolve into even more titanium-rich and magnesium-poor compositions before mixing with other ascending magmas.
This complex process ultimately gives rise to the high-Ti basalts detected by past missions.
The study also sheds light on how magma behaves deep within the Moon. At lower pressures, these melts can rise to the surface, contributing to volcanic activity.
At higher pressures, some magmas may sink back into the mantle, indicating a dynamic internal system involving both upward and downward movement, known as mantle overturn.
Beyond solving a long-standing lunar mystery, the findings carry direct implications for India’s future exploration plans. With Chandrayaan-4 expected to bring back samples later this decade, understanding where titanium-rich materials form and how they evolve will be critical for selecting landing sites and interpreting returned specimens.
Scientists say the research will help identify scientifically valuable materials on the lunar surface and guide mission planning. It also enhances the interpretation of orbital data collected by spacecraft, improving predictions about the Moon’s geology.
As India prepares to launch the Chandrayaan-4 mission to the Moon, its next giant leap in lunar exploration, this homegrown research shows how laboratory science on Earth is paving the way for discoveries beyond it.
“We are trying to understand how these unusual, titanium-rich magmas form deep within the Moon and eventually reach the surface. This is important for future missions, because when India brings back lunar rocks, we need to understand where they formed and what they reveal about the Moon’s history,” Professor Sujoy Ghosh told IndiaToday.in.
WHERE WILL CHANDRYAAN-4 LAND?
Chandrayaan-4 is set to become India’s first mission designed to collect lunar samples and return them to Earth, a complex technological step beyond the soft-landing success of Chandrayaan-3 in 2023.
Chandrayaan-4 could land in a mountainous region close to the Moon’s South Pole.
Researchers from the Space Applications Centre of the Indian Space Research Organisation (Isro) have identified the region as one of the safest and most scientifically valuable landing areas for the mission.
