QUESTION 1: Using the three provided resources, create a comparison of the available lunar in-situ resource utilization, and describe the advantages and challenges of collecting these resources.
“Advancing in Situ Resources Utilization Capabilities to Achieve a New Paradigm in Space Exploration”, gives the definition of In-Situ Resource Utilization (ISRU) as harnessing and utilizing in-situ resources by employing operations and using hardware. These resources are then used in multiples ways for instance; building structures which include satellites, rovers etc. and supplies that would aid human missions in space. During space explorations, some resources found cannot be brought back to the site and have to be collected, processed, stored and used at site where these were found. For this reason many different technologies are being developed to utilize these resources more efficiently. This process is named In-Situ Resources Utilization and it can be very beneficial for a sustainable future. ISRU presents many advantages including propulsion optimization, reduction of landing mass and decrease in health issues among the crew. The products manufactured through using ISRU are sustainable, efficient and be restocked easily. This ability will allow for long duration missions without the concern of running out of the supplies and it will also make future human missions on Mars possible.
To have a sustainable future on Earth, Mars and the moon, it is necessary to employ sustainable practices for this effort to be realized using resources gathered from the regolith and can be very beneficial. Resources gathered from regolith can also be used to make repairs in the satellites, rovers, etc. in real-time without having to wait for the supplies. Propulsion systems can be improved using ISRU as they can generate propellants using the material provided by the Earth’s resources and even space resources. If the 3D printing can be used on the moon then the propellants and pressure vessels can be generated on-site, however; the greatest challenge of 3D printing is that it is highly flammable. In this case, it would be better to look for other methods that are safe so overheating the propellant can be avoided (Sanders).
“Lunar Prospecting: Searching for Volatiles at the South Pole”, is the second article that talks about the Resource prospecting mission and the challenges that it will face during the lunar exploration. This operation is different from the previous space exploration as its success will open a gateway for future human missions on Mars. Apart from that, it is also the project that will include Permanently Shadowed Regions (PSRs) of the moon to analyze the type of volatiles that may be present in these areas. PSRs have not been touched by sunlight for millions of years and not only the temperature are below freezing point but also the environmental factors are unknown. This is the reason that pre-mission simulations are being conducted to collect data for designing the strategy and prospecting operations accordingly. The data will be collected using real-time sciences which let the real-time scientist to make decisions accordingly.
The biggest challenge is going to be PSRs exploration as the absence of light will only provide 6 hours of exploration which is an estimate as the environmental factors may reduce this time. The regolith of the PSRs may collapse under the weight of the rover and maybe too loose for the rover to drive on it properly. The texture of the regolith also needs to be taken into consideration as it may damage the wheels of the rover. For rover egress, it must have a minimum of 20 percent battery left so that it may safely return. After its return, it will need 24 hours to recharge which would mean this time would be non-productive. For this reason, the PSR exploration will be carried out at the end so that the time is used efficiently.
Efficient time utilization is extremely important as time lost can increase the cost of the mission and it should be utilized to maximize the success of the mission. To address this, parallel operations will be carried out such as prospecting, collecting and processing. All the operations of the mission will be surveillance in real-time and this will be highly beneficial when exploring PSRs. This will allow the scientist to select a safe path for the rover and change any plans or decisions in real-time. Exploring the PSRs will be the biggest challenge for the RP mission as there will be time constraints as well as unknown environmental factors. The communication networks and the DSN may make the project unfeasible so this issue needs to be resolved before the mission. Real-time science is going to be a tremendous help in this mission but to make it possible, much planning and designing are required to make the RP mission a success.
This mission requires a lot of formulations and simulations of real-time science, limited waypoint driving and basic science operations. This will allow for proper operation planning and improving the designs of the prospecting operations. Conducting the pre-mission simulations will help in overcoming the challenges of this mission and extensive training will be required for the scientists that will be a part of this mission (Trimble and Carvalho).
The article three called “Ionic Liquid Facilitated recovery of Metals and Oxygen from Regolith” discusses the importance of the regolith in harvesting the resources. Regolith is the layer of consolidated solid material covering the bedrock of the planet, for instance, the soil is the regolith of the Planet Earth. Many useful resources like Aluminum, Silicon, Oxygen and Iron, etc can be extracted from the regolith and used in the repair of satellites and rovers. These elements are also necessary for ISRU utilization by recycling these metals using the electroplating process.
For instance; Nickel-Chromium Alloy a metal-like element found in iron meteorites is utilized in heating other elements. It is a heat-resistant substance and can be used in the building of different structures. A sheet can be formed through recycling and electroplating the Nickel Chromium Alloy. This sheet can then be used as thermal protection against the sun and to avoid the corrosion of the material. Metal is recycled using electrolysis using the Bulk electroplating process, however; there is a disadvantage to this process. The disadvantage is that electroplating requires a constant flow of uninterrupted heat which means that it cannot function properly in shadowed areas and the metals depend on this process. The alternative to this method is the use of Ionic Liquids which can help in shaping the metals at room temperature. The regolith collection poses a challenge as it is found in highly stable oxides so to process these elements must be recovered back to their original and pure form. This will be disadvantageous to the RP as they require a lot of chemicals to produce heat and energy to achieve this final pure substance.
The article represents the data collected using the Ionic Liquids process that was used to recover metal from an acidic aqueous solution and this process was demonstrated at room temperature. In addition to this; successful regeneration of the Ionic Liquid reagent was observed, proving that this process was well-suited for the explorations that would be long-termed. This process will allow for the metals to be recovered and used on-site to fulfill the need of the mission in time (Karr et al.).
QUESTION 2: How does “real-time science” influence the path and the timing of the planned operation system of the lunar rover. Resource Prospector, to prospects, collect and process in-situ resources on the Moon?
“Real-time science” means the capability of decision-making at the exact moment as the operation is being carried out. This ability will allow the lunar exploration of the Resource Prospector to be more efficient as compared to the other explorations done in the past. The rover will receive the data by communicating through X band radio waves of the orbiters; while the information will be received on Earth through Deep Space Network (DSN). The authors of the article explain in detail the procedure through which the RP mission will be carried out. The scope of this mission is much wider than the previous missions as the Permanently Shadowed Regions are also included in this mission.
The Resources Prospector (RP) mission is a technological demonstration that aims to explore and examine volatiles that is present at the Lunar South pole. This mission presents many challenges as the region being explored includes an area that is permanently in shadows. These shadowed regions will pose unseen challenges that would require real-time decisions and solutions. The regions will be explored using solar-powered rovers and one of the challenges would require power and thermal management as the temperature in this area will be frigidly cold. In this case, real-time decision-making will help in selecting the path for safe entry and exit (egress). This mission will require high efficiency and faster rover egress as the area being explored will be challenging and different from previous missions (Trimble and Carvalho).
The RP mission is designed to develop a deeper understanding and fill in the gaps in our knowledge that will allow for better planning for future space missions. These gaps are called Strategic Knowledge Gaps (SKGs) which will allow humans to design and plan for human missions on Mars. The technology is being tested on the moon as it is closer to the earth and will decrease substantially while allowing us to prepare for the challenges ahead. The Lunar Exploration Analysis Group (LEAG) will work towards determining the following SKGs:
- The physical geography and accessibility of the cold traps
- The concentration of the volatiles across the surface is 1-2 meters.
- Water concentration variables
- The makeup of the volatiles
- Traffic-ability of the lunar surface
The most conclusive data collected regarding the lunar volatiles was done at Lunar Crater Observation and Sensing Satellite (LCROSS) impact site. However; the distribution of lunar volatiles at permanently shadowed areas and their spatial distribution is yet to be determined. For this purpose, prospecting is necessary which is the ability to move, sense volatiles and access them. The rover for this mission has been equipped with prospecting equipment, a drill for collecting samples and for volatiles’ extraction and analysis; an ISRU payload is also installed.
Exploration of permanently shadowed regions (PSR) is the primary mission of this exploration, however; as previously stated the PSRs are one of the coldest regions in the entire solar system due to not being exposed to sunlight for millions of years. This means that the properties and the behavior of the regolith are unknown. It may collapse under the weight of the rover or the surface much damage to the rover resulting in a driving hazard and the wheels of the rover may also sink in if the regolith is loose. These are some of the anticipated behavior that would need to be tackled in real-time. The biggest issue will be the lack of solar energy will limit the operation time down to six hours only. During these six hours, the environmental factors will slow down the progress of sample collection so it is extremely important to have real-time management capabilities. Apart from that, the rover is required to have at least 20 percent battery after its egress from the PSR and it will take 24 hours to recharge it again for another exploration during this time the samples of the collected volatiles will be analyzed in real-time. The priority of the mission is a low-risk activity for this reason the PSR explorations will be conducted at the latest as this will allow the sample collection from less unpredictable areas without any unforeseen outcomes. This exploration is predicted to have more successful science returns as opposed to the previous missions.
The mission is planned to maximize efficiency and minimize the non-productive time which means any time lost not prospecting, collecting, or processing. This lost time also includes time spent charging the rovers. To optimize the performance parallel operations will be carried out and all the data will be analyzed in real-time. The operations are divided into three tiers which include; reactive, tactical, and strategic operations. Real-time science operations will be carried out during the calibration and checkout; this will maximize the productive time.
Egress means “the action of leaving a place”; is one of the most challenging stages of the missions as the history of previous explorations has provided the evidence. The estimated time may vary greatly from the actual time spent during the exploration. For this reason, selecting a safe path is of prime importance and real-time surveillance will be very beneficial in this endeavor. To make the rover egress within six hours, a new system is being designed; this will make the egress faster than the egress of previous missions. This will require the new designs for the lander and improved operational procedures. All the preparations will be done beforehand during the cruise; this will allow the mission to be carried right after landing as minimum checks will be required after landing that will not take as much time.
Real-time science will be greatly beneficial as the prospecting, collecting and processing will be controlled as these are being carried out. This real-time data collection will allow for maximum surface time and any unpredictable circumstances can be solved efficiently. Real-time surveillance will provide the flexibility of selecting a safe path, scientific responsiveness and reduce any stress to rover drivers. A command simulator will allow the rover to quickly respond to short commands avoiding any hazardous situations. This simulator is designed keeping in mind the importance of real-time control and timely avoidance of unpredictable situations. The real-time approach includes taking stereo images of the distance up to eight meters and finding the waypoint about halfway across the field of view. While the commander of the rover will be guiding the rover through the safe selected path another pair of images will be captured, downloaded and processed. This will make the path selection extremely efficient and the planning will be carried out in real-time.
This approach of real-time science has been tested previously in payload fields and it has provided great flexibility to the missions. This approach will allow the scientists to react to the operation in real-time; making decisions and carrying them out to maximize the performance and success of the mission. One of the biggest advantages of real-time science is that it allows improved time utilization which maximizes the operation’s efficiency. It is imperative in a space mission to carry out all tasks on time for a successful expedition and it also saves cost on otherwise extremely expensive projects.
This project is still in the formulation phase as the team is trying to work out obvious concerns before the launch of the RP mission. They have been able to simulate the project which included real-time operations, path selection and some basic science operations. The data collected from these simulations have helped in the designing of the prospecting operations. Further simulations and pre-mission operations will allow us to work out any challenges that may arise during the actual mission. This lunar exploration is expected to bring in more data for the study and understanding of space regolith and volatiles as the scope of this mission is much wider than the previous exploration. The success of this exploration will open a path towards human missions on Mars and that will be an achievement of a lifetime. It will open up new prospects for space explorations in the future.
QUESTION 3: Stated in Ionic Liquid Facilitated Recovery of Metals and Oxygen from Regolith. “An Ionic liquid-based process to recover metals and oxygen from regolith has been developed and demonstrated that could make resupply of chemical reagents negligible.” In your own words, describe this closed-loop ionic liquid reprotonization process, and explain the benefits of this process to future space exploration.
Oxygen reduction is the process of separating the materials using extreme heat. During this process, it is extremely important to keep the flow of the heat constant as to prevent oxygen from reacting in a regolith. The process requires the oxygen to be oxidized while the metals are being reduced. This is beneficial as it allows the elements to be acquired and utilized on-site. Oxidization of metals changes them into a state called metal oxides during exposure to oxygen. Oxidization reduction can be used to liquidize the ionic liquids (apart from sand), allowing the metal to retain its pure quality.
The process of constantly reusing the chemicals by recycling the purity of the substance is known as a closed-loop. For operations like mining and refining in space; closed-loop ionic liquid reprotonization proves useful in the harvest and refinements of precious materials. It is also helpful in the reduction of waste material to minimize weight in space. This help in extending the life of satellites; procuring materials like platinum and bringing the collected material back to Earth.
In the article, the authors mention regolith which is inclusive of the solar energy sources, application of cement for life support and groundwork. The metal sourced is extremely important for building livable structures, providing supplies for deep space expeditions and maintenance. Refining the metal in a closed space using the common methods of refinement can be severely hazardous for the ship and its crew. This will also be a very expensive process to perform in a ship so preparing a boundless supply and autonomous method of preparing raw material for 3d printers in space using this method will be very beneficial.
Shipping the supplies and spare parts for rovers from the earth can be very expensive so the ability to produce these materials outside of the Earth will not only be phenomenal but also cost-effective. Using the metals found in the regolith to manufacture parts for the rover will extend its life and repairs would be made on time without waiting for the supplies to come from Earth. The elements that are not present or difficult to find in space’s regolith like Nickel Chromium Alloy can be recycled completely. Rovers are ideal for gathering resources and delivering them for different operations and uses. ISRU is a step forward towards the goals of sustainability and resource utilization on Earth (Karr et al.).
Karr, Laurel, et al. “Ionic Liquid Facilitated Recovery of Metals and Oxygen from Regolith.” 2018 AIAA SPACE and Astronautics Forum and Exposition, American Institute of Aeronautics and Astronautics, 2018. DOI.org (Crossref), https://doi.org/10.2514/6.2018-5291.
Sanders, Gerald B. “Advancing In Situ Resource Utilization Capabilities To Achieve a New Paradigm in Space Exploration.” 2018 AIAA SPACE and Astronautics Forum and Exposition, American Institute of Aeronautics and Astronautics, 2018. arc.aiaa.org (Atypon), https://doi.org/10.2514/6.2018-5124.
Trimble, Jay, and Robert Carvalho. Lunar Prospecting: Searching for Volatiles at the South Pole. 2016. ResearchGate, https://doi.org/10.2514/6.2016-2482.