Indian Space Research Organisation (ISRO) has received a patent for its method of manufacturing highland lunar soil simulant or moon soil which was prepared to create an artificial moon surface as a part of 2019’s Moon landing mission Chandrayaan-2 so that the Vikram lander and Pragyaan rover could be tested. This soil simulant represents the regolith (loose unconsolidated rock and dust that sits atop a layer of bedrock) of lunar highland region.
- It is made in bulk from anorthosite rocks, a sample similar to regolith identified and picked out from Sittampundi Anorthosite Complex, almost 67 km from Salem, in Tamil Nadu.
- Recalling, the mission Chandrayaan-2, with an orbiter, a rover and a probe, successfully placed the orbiter which will have an extended lifespan of seven years, while the lander crashed on the Moon’s South Pole in September 2019.
About Patent:
On May 18, the Indian Patent Office granted a patent to ISRO for the method of manufacturing highland lunar soil simulant. The invention satisfied all aspects, including mineralogy, bulk chemistry, grain size distribution and geo-mechanical properties. The patent is valid for 20 years from the date of filing the application, i.e., May 15, 2014.
- Inventors: I. Venugopal, S.A. Kannan, Shamrao, V. Chandra Babu (all from ISRO), S. Anbazhagan, S. Arivazhagan, C.R. Paramasivam, M. Chinnamuthu (all from the Department of Geology, Periyar University, Salem, Tamil Nadu) and K. Muthukkumaran from the National Institute of Technology, Tiruchirappalli, Tamil Nadu.
Need for indigenous Lunar soil:
The surface of the earth and that of the moon are entirely different. So there is a requirement of artificial moon surface for lunar exploration as it requires a full understanding of the physical and chemical properties of lunar surface soil.
- Also, importing lunar soil like substance from the United States (US) was a costly affair as its need was about 60/70 tonnes of soil.
Current status of lunar soil simulant:
There are more than 30 lunar simulants that have been produced to date, some of which have been exhausted. Most of the countries produced simulants representing the lunar mare region. It should be noted that there are bright and dark areas on the Moon’s surface. The dark areas are called Maria or mare, which are mostly flat, while the bright areas are highlands which are heavily cratered and mountainous and occupies 83% of the lunar surface.Â
- However, only a limited number of simulants represents the regolith of the lunar highland region.
How it is prepared?
Near Salem in Tamil Nadu, there were anorthosite rocks that were similar to the features of moon soil or regolith. The ISRO finalised to take these rocks from Sithampoondi and Kunnamalai villages in Tamil Nadu for moon soil.
After that the rocks were crushed to the required size and moved to Bengaluru, Karnataka where its Lunar Terrain Test Facility was located and the test bed was created.
- The simulant is almost equivalent to the regolith of the lunar highland region and comparable with Apollo 16 return samples.
How will it be useful?
-For scientific studies of lunar terrain relating to mobility/trafficability of rover for scientific explorations.
-To study geo-technical/mechanical properties of lunar soil for understanding the engineering behaviour of lunar regolith.
-To carry out fundamental research work (theoretical and experimental) to postulate a broad design philosophy for realising civil engineering structures on the Moon surface, and to make a pathway to lunar locomotive engineering.
About Lunar Soil:
The composition of lunar soils has two broad groups viz:
- The highland soils, which are developed on anorthositic bedrock. These are enriched in aluminium and calcium.
- Mare soils, which are developed on basaltic bedrock, are relatively enriched in iron, magnesium and titanium.Â
About ISRO:
Headquarters– Bengaluru, Karnataka
Parent organisation– Department of Space
Director– Kailasavadivoo Sivan