3D printing of Martian and Lunar analogue rocks

Abstract

The near-future colonisation of Mars and the Moon warrants suitable construction materials to be prearranged. Selecting appropriate and readily available rocks, as well as obtaining a cementing medium to make the rocks feasible for 3D printing, provide obstacles that must be overcome before preparing for Martian and Lunar surface colonisation. Olivine, a mineral of significant presence, is widely distributed across the planetary surface of Mars. However, it is noteworthy that Nili Fossae, a region encompassing Noachian-aged rocks, exhibits particularly prominent accumulations of this material. A notable occurrence of a substantial olivine-rich outcrop can be observed in Ganges Chasma, which is situated on the eastern side of Valles Marineris (Linda M.V. Martel 2007). Calcium or iron carbonates were identified within a crater situated on the rim of Huygens Crater, which is situated in the Iapygia quadrangle. The excavation of material resulting from the impact event that formed Huygens has led to the exposure of rim materials (NASA JPL 2011). The calcium carbonate may be used as a raw material for cement. The terrestrial analogue of the olivine mineral is collected from the ultramafic complex of Chalk Hills, Salem, Tamil Nadu. The monomineralic rock Dunite is pulverised in a jaw crusher and sieved using a mechanical sieve shaker. Two different types of cement are intended for making cubical blocks of 4 cm in size. Pulverised sedimentary Marly lime stones were collected from sedimentary deposits in Ariyalur district, Tamil Nadu, which may be an analogue of the sedimentary sequence reported from Gale crater. The pulverised and sieved fractions are mixed in equal proportions to use it as cement. Heated marly lime stones (calcined lime) resembling a possible cement we can prepare from CaCO3 under the effects of an ionising radiation dose at a minimum power of absorbed radiation equal to 0.5 Mrad/s (United States Paten 3,940,324) The calcined lime is used as the binding material of olivine for making 4 cm3 blocks. The blocks are made with olivine (dunite) and limestone powder in five different proportions ranging from 50:50 to 90:10. Similar proportions are maintained for the olivine and calcined lime mixtures. With the possibility of microbial-induced calcite precipitation (Rashmi Dikshit et al., 2021), taking up a limestone medium as a binder for Lunar soil will enhance the possibility of building a robust structure. Lunar analogue soil is made from the anorthosite rocks from the Sittampundi anorthosite complex, located in South India (Venugopal et al., 2020). The anorthosite is pulverised and sieved using a mechanical sieve shaker. Eleven different size fractions are separated, viz., ASTM 230+, ASTM 230, ASTM 180, etc. The different size fractions are taken in equal proportions and thoroughly mixed with marly limestone powder in different ratios, like 50:50 to 90:10. After 14 days of curing and drying under nominal atmospheric conditions, the blocks will be treated in liquid nitrogen and Thermovac lab to simulate temperature and pressure variations in space before being tested for engineering properties.