Value of Information for Lunar Ice Exploration

As the NASA-led return to the Moon swings into action over the next decade via Project Artemis, this overview paper considers the prospects for a new “lunar economy” emerging from the 2030’s. If Moonbases can be established and viable resource utilisation begun, with public and privately funded research stations and lunar tourism occurring, the Moon could act as a “testbed” and an enabler for interplanetary travel beyond to Mars and then across the wider Solar System. The exploration of the Moon and its resource utilisation would focus on the availability and viability of polar water ice resources, solar power usage, hydrogen and oxygen extraction for air and fuel via In Situ Resource Utilisation (ISRU), plus research into rare minerals present in the lunar regolith and their possible extraction. The viability of helium 3 mining, possible high temperature annealing of metals and 3D printing using lunar dust is noted. With plans in place to move forward with NASA/ ESA/JAXA’s “Project Artemis” and the orbiting Gateway station, plus private initiatives making use of SpaceX’s Starship and Blue Origin’s lunar landers, cheaper access to the lunar surface will evolve. Considering the actual ownership of the Moon and lunar resources, international clarification is required – many consider that the 1967 Outer Space Treaty background needs restructuring and the gap in resource ownership and exploitation law needs new international agreement. It is considered that the lunar economy could prosper via lunar ice ISRU, possibly making use of fuel and oxygen availability for onward travel from the lunar surface, perhaps via “mass drivers” to lunar orbit. Spacecraft might then refuel initially for lunar-Earth travel. Technology development for lunar landing systems and surface habitation will enable future deep space lunar-Mars trips and eventually Mars-base settlements, with travel across the Solar System gradually evolving. Keywords: Lunar Economy, Project Artemis, Moonbases, ISRU, Lunar Ice, Space Tourism, Lunar Regolith, Lunar Observatories, Newspace, 3D Printing, Helium 3, Space Law, Lunar Gateway Station, Starship HLS, Blue Moon HLS, Lunar Mass Drivers, Mars Colonies

Selected in 2019 as a NASA SIMPLEx mission, Lunar Trailblazer is in implementation for flight system delivery at the end of 2022. The mission&#x0027;s goal is to understand the form, abundance, and distribution of water on the Moon and the lunar water cycle. Lunar Trailblazer also collects data of candidate landing sites to inform planning for future human and robotic exploration of the Moon and evaluate the potential for in situ resource utilization. Lunar Trailblazer&#x0027;s two science instruments, the High-resolution Volatiles and Minerals Moon Mapper (HVM3) and the Lunar Thermal Mapper (LTM) provide simultaneous high-resolution spectral imaging data to map OH/water, crustal composition, and thermophysical properties from a <tex>$100\pm 30$</tex> km lunar polar orbit. The &#x223C;210-kg flight system deploys from an ESPA Grande and utilizes a &#x223C;1000 m/s <tex>$\Delta\mathrm{V}$</tex> hydrazine chemical propulsion system, similar to that employed by GRAIL. Trailblazing elements include the novel state-of-the-art dataset collected at substantially reduced price point, fully geographically co-registered data products delivered to the Planetary Data System, planetary mission team demographics, Caltech campus mission operations, and student staffing of select mission ops roles. Lunar Trailblazer&#x0027;s pioneering development is providing key lessons learned for future planetary small spacecraft.

The presence of water on the Moon has been indicated by various remote-sensing observations and analyses of returned samples. Several missions are planned to conduct new in situ research on the lunar surface to directly observe and characterize lunar water. A comprehensive characterization of the present forms of water, their abundance, spatial distribution, temporal variation, and possible origin is required to understand the lunar water cycle and the relevance of individual source and sink mechanisms and transformations between the involved volatile species. These processes extend over vastly different scales, and the governing parameters are often insufficiently constrained by experimental and observational data. Here, I present a brief overview of the current state of knowledge on the lunar water cycle, its relevance for lunar science and exploration, and some of the main challenges of modeling and future in situ analyses aiming to substantially advance the understanding of lunar water occurrences.

Miniaturized time-of-flight mass spectrometer for lunar water detection

Development of a micro-ice production apparatus and NIR spectral measurements of frosted minerals for future lunar ice exploration missions

To prepare for the lunar water exploration in the Chinese Lunar Exploration Project IV, a new apparatus for studying characteristics of the water vapor conductance and water detection at low temperatures was built based on the flowmeter method, and the performance of the miniature time-of-flight mass spectrometer (TOF-MS) for water detection in the range −20 to 20 °C was measured. The through-put within the range of 3 × 10−9–9 × 10−6 Pa m3 s−1 was provided at temperatures in the range −60 to 20 °C. The conductance of the orifice with a diameter of 21 µms for three gases (N2, Ar, and H2O) was measured at low temperatures. The diameter change of the metal orifice caused by the cold contraction in the molecular flow state is the main factor affecting the conductance, and the viscosity characteristic of gas in the viscous flow state is the main factor affecting the conductance. Therefore, the conductance of the orifice increases with the decreasing temperature when the through-put is high. In addition, the water vapor can be stably supplied by the orifice under low temperatures, and the conductance of water vapor through the orifice is measured through the on-line method and the time-ratio method. The adsorption rate and amount of water vapor on the metal surface increase with the decreasing temperature, hence the concentration of water molecules in the test dome significantly decreases as the temperature decreases. Finally, the through-put of water vapor of 8.75 × 10−8 Pa m3 s−1 was detected by the miniature TOF-MC at −20 °C on the apparatus.

The search for exploitable deposits of water and other volatiles at the Moon’s poles has intensified considerably in recent years, due to the renewed strong interest in lunar exploration. With the return of humans to the lunar surface on the horizon, the use of locally available resources to support long-term and sustainable exploration programs, encompassing both robotic and crewed elements, has moved into focus of public and private actors alike. Our current knowledge about the distribution and concentration of water and other volatiles in the lunar rocks and regolith is, however, too limited to assess the feasibility and economic viability of resource-extraction efforts. On a more fundamental level, we currently lack sufficiently detailed data to fully understand the origins of lunar water and its migration to the polar regions. In this paper, we present LUVMI-X, a mission concept intended to address the shortage of in situ data on volatiles on the Moon that results from a recently concluded design study. Its central element is a compact rover equipped with complementary instrumentation capable of investigating both the surface and shallow subsurface of illuminated and shadowed areas at the lunar south pole. We describe the rover and instrument design, the mission’s operational concept, and a preliminary landing-site analysis. We also discuss how LUVMI-X fits into the diverse landscape of lunar missions under development.

Chapter 9 - Lunar explorations—Discovering water, minerals, and underground caves and tunnel complexes

Owing to the Moon’s rough surface, there is a growing controversy over the conclusion that water ice exists in the lunar permanently shadowed regions (PSRs) with a high circular polarization ratio (CPR). To further detect water ice on the Moon, an innovative design method for spaceborne synthetic aperture radar (SAR) system is proposed, to obtain radar data that can be used to distinguish water ice from lunar regolith with a small difference in the dielectric constants. According to Campbell’s dielectric constant model and the requirement that SAR radiometric resolution is smaller than the contrast of targets in images, a newly defined SAR system function involved in the method is presented to evaluate the influence of some system parameters on the water ice detection capability of SAR. In addition, several simulation experiments are performed, and the results demonstrate that the presented SAR design method may be helpful for lunar water ice exploration.

The study of water ice on the moon is related not only to the formation and evolution of the moon but also to the utilization of lunar resources and the problem whether human beings can go into the depth of the universe with the help of the moon. This paper reviewed the progress of lunar water ice exploration and summarized the research status both in China and abroad. The authors analyzed some impact craters in the north moon and discussed whether there exists water ice or not by means of the polarization synthetic aperture Radar,the data of miniature radio frequency( Mini- RF) and the characters of polarization SAR as well as the reflection of water ice. The Mini- RF CPR data analysis reveals that the north- pole of the moon probably contains water ice,but the water quantity and the mode of occurrence require further investigation.

The EuroMoonMars Programme started in 2009 by ILEWG, ESA ESTEC, NASA, VU Amsterdam and supported by various space agencies, universities and academic or industrial partners has to bring together : space science and astronomy, Earth and planetary sciences and biology, technology, field work campaigns in extreme environments, resource utilisation and economy, human factors, international cooperation. Space and society, bridging to Arts and social sciences through the ArtMoonMars initiative.We shall describe how EuroMoonMars can contribute to European astronomy and space science: public and political engagement education in areas of education, research, innovation, culture, youth and sport policies, and industry, digital single market, space and safety, policies .The International Lunar Exploration Working Group (ILEWG) is a public forum sponsored by the world's space agencies to support "international cooperation towards a world strategy for the exploration and utilization of the Moon - our natural satellite" (International Lunar Workshop, Beatenberg (CH), June 1994). ILEWG was founded by several space agencies: ASA, ASI, BNSC, CNES, DARA, ESA, ISAS, NASA, NASDA, RSA. ILEWG has been organising since 1994 the ICEUM International Conferences on Exploration &amp;amp; Utilisation of the Moon with published proceedings, and where community declarations have been prepared and endorsed by community participants. ILEWG has co-organised and co-sponsored lunar sessions at EGU, COSPAR, EPSC. Declarations from ICEUM conferences&amp;#160; cover all aspects of science, technology, cooperation, industry, society and inspiration. ICEUM13 took place together with COSPAR in Pasadena in 2018, and ICEUM14 with EPSC-DPS in Geneva in 2019. Next ICEUM15 is to take place with COSPAR B/PEX symposia (co-chairs: C. Pieters, B. Foing, G. Schmidt, C. Heinicke), in Sydney in January 2021.ILEWG founded in 2009 the EuroMoonMars initiative, which comprises field campaigns in Moon-Mars analogue environments.The EuroMoonMars field campaigns have been organised in specific locations of technical, scientific and exploration interest. The campaigns started with EuroGeoMars2009 (Utah MDRS, 24 Jan-1 Mar 2009) with ILEWG, ESA ESTEC, NASA Ames, VU Amsterdam and GWU and continued yearly at MDRS and other extreme field sites on Earth.The EuroMoonMars campaigns consist of research activities for data analysis, instruments tests and development, field tests in Moon-Mars analogues, pilot projects, training and hands-on workshops and outreach activities.In 2019 ILEWG contributed to IgLuna first ESA Lab inter-University demonstrator project,&amp;#160; hosted by the Swiss Space Centre (SSC) with the vision to create an analogue habitat inside lunar ice caps. The campaigns were held from 17&amp;#8211;30 June 2019 and involved 18 student teams from 9 countries across Europe. The students developed modular demonstrators and tested them during a field test conducted inside the moon-like extreme environment of the Glacier Palace inside the Zermatt Matterhorn glacier.Currently, ILEWG is collaborating with the International Moonbase Alliance (IMA)] and the Hawaii Space Exploration Analog and Simulation (HI-SEAS) on a series of EuroMoonMars, IMA and HI-SEAS (EMMIHS) campaigns, at the HI-SEAS analogue facilities in Hawaii.ArtMoonMars, Moon Village &amp;amp; ITACCUS (IAF ITACCUS Committee on Socio Cultural Utilisation of Space) activities were performed, with emphasis on events and workshops. The Moon Village is an open concept proposed with the goal of a sustainable human and robotic presence on the lunar surface as an ensemble where multiple users can carry out multiple activities. We want to involve everybody including Socio cultural and Artistic aspects. Why ArtMoonMars? Artists can convey multiple messages of the community including planetary science, life sciences, astronomy, fundamental research, resources utilisation, human spaceflight, peaceful cooperation, economical development, inspiration, training &amp;amp; capacity building.Referenceshttps://en.wikipedia.org/wiki/International_Lunar_Exploration_Working_Group

A full-size model of a lunar rover using a laser energy transportation to confirm directly the existence of ice on the moon has been fabricated and 100 m energy transportation test has been successfully performed. Problems to be solved to realize an actual lunar ice exploration mission are discussed.

Aiming at the problem that it is difficult to collect the subsurface lunar water ice samples quickly due to the cementation-hardening of ice and soil at extremely low temperature in the permanent shadow regions, a novel lunar water ice sampling system is proposed, which uses kinetic energy penetration to efficiently expose the subsurface lunar water ice and uses manipulator to accurately collect and transfer the lunar soil samples. Based on the analysis of the working strategy of the sampling system, an engineering prototype of penetrating modular was designed and developed, and its penetration efficiency was tested based on the principle that the mechanical characteristics are equivalent. The test results show that the penetrating modular can penetrate into the target whose uniaxial compressive strength(UCS) is about 30Mpa (equivalent to the UCS of the simulated lunar water ice) with low power consumption and high efficiency, the penetration depth can reach 234mm, and the penetration time is less than 1s.

Observations by the Lunar Prospector and the Lunar Atmosphere and Dust Environment Explorer spacecraft suggest the existence of a near-global deposit of weakly bound water ice on the Moon, extending from a depth of a decimetre to at least three metres. The existence of such a layer is puzzling, because water ice would normally desorb at the prevailing temperatures. We here determine the conditions for long-term thermal stability of such a reservoir against solar and meteoroid-impact heating. This is done by using the highly versatile thermophysics code nimbus to model the subsurface desorption, diffusion, recondensation, and outgassing of water vapour in the porous and thermally conductive lunar interior. We find that long-term stability against solar heating requires an activation energy of $\sim 1.2\, \mathrm{eV}$ in the top metres of lunar regolith, and a global monthly night time exospheric freeze out amounting to $\sim 1$ tonne. Furthermore, we find that a lower $\sim 0.7\, \mathrm{eV}$ activation energy at depth would allow for water diffusion from large (0.1–$1\, \mathrm{km}$) depths to the surface, driven by the radiogenically imposed selenotherm. In combination with solar wind-produced water, such long-range diffusion could fully compensate for meteoroid-driven water losses. These results are significant because they offer quantitative solutions to several currently discussed problems in understanding the lunar water cycle, that could be further tested observationally.

Over the last few decades, observations have revealed the presence of water ice at the lunar poles and upended the notion of a completely dry lunar surface. These ice deposits hold information about the history of water on the Moon and in the Earth-Moon system, and are potential resources for future human exploration of the Moon. However, they remain relatively uncharacterized in abundance, distribution, and composition. Foremost among the open questions about lunar ice are: What were the sources of ice on the Moon&amp;#8217;s surface, and how much water could have been delivered? The three most likely sources of lunar water ice are: (1) impact delivery from asteroids and/or comets, (2) solar wind ion implantation, and (3) volcanic outgassing of volatiles from the lunar interior. Here, we assess the viability of a volcanic source for water ice accumulated at the lunar poles.[1] first suggested the occurrence of a volcanically induced transient atmosphere on the ancient Moon that would have been dominated by CO, but with a significant amount of H&amp;#173;2O. Further studies investigated the dynamics [2] and atmospheric escape processes [3] that would have affected such an atmosphere. [4] later suggested that a large number (30,000-100,000) of eruptions would have created less massive atmospheres during the Moon&amp;#8217;s most volcanically active period (4-2 Ga).We model the generation of transient atmospheres from 50,000 eruptions from 4 to 2 Ga, the subsequent escape of these atmospheres to space, and the concurrent accumulation of atmospheric water vapor as ice at the lunar poles [5]. The molecular composition of the modeled atmospheres is determined using estimates of outgassed volatile content for lunar volcanic eruptions derived from analyses of Apollo samples [4,6]. We model three atmospheric escape processes: (1) Jeans escape, (2) sputtering escape, and (3) photodissociative escape [3], and model photodissociative escape separately for both CO and H2O. We use maximum annual surface temperatures [7] measured by the Diviner Lunar Radiometer Experiment on board the Lunar Reconnaissance Orbiter [8] to calculate ice accumulation rates for each Diviner pixel within 30&amp;#176; latitude of the poles [5].We find that water vapor is removed from a typical transient atmosphere in about 50 years via ice accumulation and photodissociative escape. About 41% of the total water vapor mass outgassed from 4 to 2 Ga is accumulated as ice on the surface. This demonstrates that a significant amount of ice (~8&amp;#215;1015 kg) could have been sourced from volcanic outgassing, though atmospheric escape processes also strongly control the efficacy of this mechanism.&amp;#160;[1] Needham, D. H. and Kring, D. A. (2017) EPSL, 478, 175-178. [2] Aleinov, I., et al. (2019) GRL 46, 5107-5116. [3] Tucker, O. J., et al. (2021) Icarus, 359, 114304. [4] Head, J. W., et al. (2020) GRL, 47, e2020GL089509. [5] Wilcoski, A. X., et al. (2022) PSJ 3.5, 99. [6] Rutherford, M. J., et al. (2017) Amer. Mineralogist, 102, 2045-2053. [7] Landis, Margaret E., et al. (2022) PSJ 3.2, 39. [8] Paige, D. A., et al. (2010) Space Sci. Rev., 150, 125- 160.