STUDY ON GEOMECHANICAL PROPERTIES OF LUNAR SOIL SIMULANT (LSS-ISAC-1) FOR CHANDRAYAAN MISSION

Abstract Under Chandrayaan - II mission, simulation studies on lunar terrain were required for evaluation of the performance of rover and lander. In order to carry out mobility tests of a rover, it was required to prepare a lunar terrain testbed, which required a large quantity of lunar soil to represent the terrain conditions of the Moon. Under such compelling circumstances, U R Rao Satellite Centre (URSC), Indian Space Research Organization (ISRO), Bangalore, India has decided to manufacture indigenously lunar highland soil simulant, which can represent bulk chemistry, mineralogy and geomechanical properties of actual lunar highland soils brought by Apollo-16 mission of USA. This paper presents the process of manufacturing new lunar highland soil simulant (LSS-ISAC-1) and its various geomechanical properties such as cohesive modulus of deformation, frictional modulus of deformation, sinkage exponent, cohesion stress, angle of internal friction, shear deformation modulus and bulk density. The same were compared with the properties of actual lunar highland soil brought to the Earth by the Apollo-16. This new lunar highland soil simulant is being used for all qualifying tests required to be performed for the indigenously developed rover and the lander of the Chandrayaan mission.