Lunar sourcebook. A user's guide to the moon

Extraterrestrial construction materials

Materials and design concepts for space-resilient structures

Regolith-based additive manufacturing for sustainable development of lunar infrastructure – An overview

A review towards the design of extraterrestrial structures: From regolith to human outposts

Extra-terrestrial construction processes – Advancements, opportunities and challenges

For a sustainable human presence on the Moon, it is critical to develop technologies that could utilise the locally available resources (a.k.a. in situ resource utilisation or ISRU) for habitat construction. As the surface soil is one of the most widely available resources at the Moon, we have investigated the viability of microwave heating of a lunar soil simulant (JSC-1A). JSC-1A was thermally treated in a bespoke microwave apparatus using 2.45 GHz frequency, using five different microwave powers in the range of 250 W to 1000 W. The structural properties of the resulting products were analysed to determine whether their microstructures and mechanical strengths differ under different input powers; and whether input power plays a crucial role in triggering thermal runaway, for identifying the optimum power for developing a microwave-heating. Our key findings are: (i) the higher input powers (800 W and 1000 W) generate the highest yields and microstructures with the greatest mechanical strengths, at the shortest fabrication times, and (ii) thermal runaway improves the microwave heating efficiency despite the rapid increase in temperature, once it is triggered. Our findings are of key importance for developing a microwave-heating payload for future lunar ISRU demonstration missions, contributing towards 3D printing-based extra-terrestrial construction processes.

/pdf/investigating-the-microwave-heating-behaviour-of-lunar-soil-8pha8lsu3z.pdf

Investigating the microwave heating behaviour of lunar soil simulant JSC-1A at different input powers

Corrigendum to "Extra-terrestrial construction processes - Advancements, opportunities and challenges" [Adv. Space Res. 60 (2017) 1413-1429]

Microwave Heating of Lunar Simulants JSC-1A and NU-LHT-3M: Experimental And Theoretical Analysis

For a sustainable human presence on the Moon, it is critical to develop technologies that could utilise the locally available resources (a.k.a. in situ resource utilisation or ISRU) for habitat construction. As the surface soil is one of the most widely available resources at the Moon, we have investigated the viability of microwave heating of a lunar soil simulant (JSC‑1A). JSC‑1A was thermally treated in a bespoke microwave apparatus using 2.45 GHz frequency, using five different microwave powers in the range of 250 W to 1000 W. The structural properties of the resulting products were analysed to determine whether their microstructures and mechanical strengths differ under different input powers; and whether input power plays a crucial role in triggering thermal runaway, for identifying the optimum power for developing a microwave‑heating. Our key findings are: (i) the higher input powers (800 W and 1000 W) generate the highest yields and microstructures with the greatest mechanical strengths, at the shortest fabrication times, and (ii) thermal runaway improves the microwave heating efficiency despite the rapid increase in temperature, once it is triggered. Our findings are of key importance for developing a microwave‑heating payload for future lunar ISRU demonstration missions, contributing towards 3D printing‑based extra‑terrestrial construction processes. A new wave of space exploration and the ambition for a permanent presence of humans on other planetary bodies such as the Moon have necessitated research into the construction and resource utilisation in extra-terrestrial environments 1 . The current efforts are directed towards building lunar habitats and infrastructures, such as radiation protection shields, surface pavements, bridges, dust-shield walls and spacecraft landing pads using resources available in-situ. A key technology most likely to be and (ii) is a in a ing. as an macroscopic phenomenon to the dielectric properties A dramatic temperature increase the the of a local “hotspot” It is one of the most critical when processing material with temperature-dependent dielectric properties which is to the heating of lunar soil/simulants. The findings from this work have been used to suggest the optimal input power for microwave heating of lunar soil, and the minimum input power for future lunar in situ Resource Utilisation (ISRU) activities, including the development of a microwave-heating to identify fundamental criteria for a microwave heating-based resource extraction and 3D printing platform as of extra-terrestrial construction process. and iron-rich olivine, and a focused beam for the other mineral phases. The hardness and elastic modulus of the specimens were measured using a NANOINDENTER XP (MTS, USA). Indentations were performed using a diamond-tipped BERKOVICH indenter. The testing temperature was maintained within the range of 20–22 °C to reduce thermal drift. For each surface location tested, 64 separate indentations were performed over an area of dimensions 70 × 70 µm. Specimens were indented at a strain rate of 0.05 s −1 to a maximum depth of 500 nm. Elastic modulus and hardness were calculated using the Oliver-Pharr method 51 , in which a second-order polynomial is fit to the unloading section of the load–displacement data. The Poisson’s ratio of the material was assumed to be 0.3. True Density analysis of each specimen was performed by measuring the broken fragments of each specimen generated via microwave heating using the Micromeritics AccuPyc II 1340 Gas Pycnometer. The volume of each specimen was calculated using Archimedes principle 52 20 times for each specimen. The volume was used in conjunction with the specimen mass to calculate the specimen density.

Vibha Levin Prabhu

Papers

Extra-terrestrial construction processes – Advancements, opportunities and challenges

Investigating the microwave heating behaviour of lunar soil simulant JSC-1A at different input powers

Corrigendum to "Extra-terrestrial construction processes - Advancements, opportunities and challenges" [Adv. Space Res. 60 (2017) 1413-1429]

Microwave Heating of Lunar Simulants JSC-1A and NU-LHT-3M: Experimental And Theoretical Analysis

Open Research Online Investigating the microwave heating behaviour of lunar soil simulant JSC-1A at diﬀerent input powers