PS5.3 | Lunar Science, Exploration & Utilisation
EDI
Lunar Science, Exploration & Utilisation
Co-organized by GI3
Convener: Ottaviano Ruesch | Co-conveners: Joana S. Oliveira, Rachael Martina Fernando MarshalECSECS, Chrysa Avdellidou, Bernard Foing
Orals
| Tue, 25 Apr, 14:00–15:45 (CEST)
 
Room M2
Posters on site
| Attendance Tue, 25 Apr, 16:15–18:00 (CEST)
 
Hall X4
Posters virtual
| Attendance Tue, 25 Apr, 16:15–18:00 (CEST)
 
vHall ST/PS
Orals |
Tue, 14:00
Tue, 16:15
Tue, 16:15
The Lunar Science, Exploration & Utilisation Session will address the latest results from lunar missions: from ground-based and satellite measurements, to lunar meteorites research, terrestrial analog studies, laboratory experiments and modelling. All past/current results as well as future exploration ideas and prospects are welcome. The session aims to bring together contributions on theoretical models concerning the deep interior and subsurface structure and composition; observations of the surface morphology and composition; analyses of the atmospheric composition and dynamics; the interaction with the solar wind, analog studies and future habitability of the Moon.
This session also aims at presenting highlights of relevant recent results regarding the exploration and sustainable utilization of the Moon through observations, modelling, laboratory. Key research questions concerning the lunar surface, subsurface, interior and their evolution will be discussed. In detail, the topics of interest for this session include:
-Recent lunar results: geochemistry, geophysics in the context of open planetary science and exploration;
-Synthesis of results from Clementine, Prospector, SMART-1, Kaguya, Chang’e 1, 2 and 3, Chandrayaan-1, LCROSS, LADEE, Lunar Reconnaissance Orbiter, Artemis and GRAIL;
- First results from Chang'E 4, Chandrayaan2, Chang’E5, Commercial Lunar Payload;
- Goals and Status of missions under preparation: orbiters, Luna25-27, SLIM, GLXP legacy, LRP, commercial landers, Future landers, Lunar sample return missions;
- Precursor missions, instruments and investigations for landers, rovers, sample return, and human cis-lunar activities and human lunar surface sorties with Artemis and Intl Lunar Research Station;
- Preparation for International Lunar Decade: databases, instruments, missions, terrestrial field campaigns (eg EuroMoonMars), In-Situ Resources, ISRU, support studies;
- ILEWG and Global Exploration roadmaps towards a global robotic/human Moon village;
Note that this session is open to all branches of lunar science and exploration, and is intended as an open forum and discussion between diverse experts and Earth geoscientists and explorers at large. The session will include invited and contributed talks as well as a panel discussion and interactive posters with short oral introduction. It is co-sponsored by ILEWG, COSPAR, IAF International Astronautical Federation, Space Renaissance International and MVA Moon Village Association.

Orals: Tue, 25 Apr | Room M2

Chairpersons: Ottaviano Ruesch, Rachael Martina Fernando Marshal, Joana S. Oliveira
14:00–14:02
Lunar Science
14:02–14:12
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EGU23-8116
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solicited
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Virtual presentation
Thomas Kruijer, Gregory Archer, and Thorsten Kleine

Key events in the early history of the Moon include its formation by a giant impact, the solidification of the lunar magma ocean, and late accretion. The 182Hf-182W system (t1/2 ~9 Ma) constitutes a versatile tool to study each of these processes because they can all result in measurable 182W variations. Here we review the 182W record of lunar rocks and highlight key constraints on the early evolution of the Moon. Tungsten isotope studies on lunar samples demonstrate that there are no resolvable 182W variations within the Moon, implying that lunar magma ocean differentiation later than ~70 Ma after Solar System formation. Nevertheless, the Moon is characterized by a uniform ~25 parts-per-million 182W excess over the present-day bulk silicate Earth (BSE). One possibility is that this 182W difference is radiogenic in origin, in which case the Hf-W system can potentially be used to date the formation of the Moon. However, this interpretation is problematic for two reasons. First, mixing processes during the giant impact very likely modified the 182W composition of the Moon and led to distinct initial 182W compositions of the Moon and Earth. Second, the pre-late accretion 182W compositions of the Moon and BSE overlap within uncertainty, and hence there is no resolved radiogenic 182W difference between the BSE and the Moon. Consequently, the Hf-W system does not provide reliable constraints on the age of the Moon. Instead, the Hf–W systematics are fully consistent with 'young' ages of the Moon, well after the effective lifetime of 182Hf.

How to cite: Kruijer, T., Archer, G., and Kleine, T.: Tungsten isotopes and the early evolution of the Moon, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-8116, https://doi.org/10.5194/egusphere-egu23-8116, 2023.

14:12–14:15
14:15–14:25
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EGU23-5929
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ECS
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On-site presentation
Shreekumari Patel, Animireddi V Satyakumar, Paras Solanki, and Mohamed R El-maarry

The 64 km wide Ohm crater is a complex impact crater located on the northern side of the lunar farside. In this study, we generated abundance maps for FeO and TiO2 as well as Spectral Parameter maps to determine the composition. Orthopyroxene and Clinopyroxene, two mafic minerals, are present in the Ohm crater, according to spectral analyses of M3 data. A geostatistical technique is used to optimize the variation trend of diagnostic characteristics across different sites. We noticed that Opx dominates the rest of the crater, while Cpx dominates the western portion of Ohm. Opx denotes sources from above and/or below the crust-mantle boundary, whereas Cpx suggests impact melt crystallization of an anorthositic target crust. The NASA mission GRAIL, which is specifically designed to study gravity anomalies, has found negative anomalies near the Ohm crater that may indicate a thicker crust beneath the crater. Unequal Bouguer gravity anomalies and negative anomalies have been found in the vicinity of the Ohm crater, but they are not clearly connected to the internal morphology. Surface morphological features have no connection to these anomalies of uneven gravity. In addition, the Bouguer gravity signature may be affected by pre-existing subsurface density structure, and post-impact events (such as magmatism), which could account for some of the observed scatter. The regional gravity anomaly also indicates low values in the Ohm crater, suggesting that the thicker crust and the source of the geochemical anomalies are at deeper levels. Strong negative anomalies are seen in the predicted residual gravity data close to the Ohm crater, which suggests low-density bodies at the crustal level. We propose that the pyroxenes are the end product of impact melt crystallization based on regional and residual gravity anomalies, compositional and mineralogical features of the Ohm crater, and geophysical data. Ejecta from the SPA, Orientale, and Mascon Hertzsprung basins, which may or may not have differed from impact melt formed during the Ohm impact event, should also be looked at when analyzing the distribution of mafic minerals throughout the crater. The GRAIL crustal thickness model-1 for the Ohm crater indicates a thicker crust, demonstrating that the mantle upliftment is not the underlying cause of the geochemical anomalies in this area.

Acknowledgement: S. M. Patel and M. R. El-maarry acknowledge support for this work through an internal grant (8474000336-KU-SPSC).

How to cite: Patel, S., Satyakumar, A. V., Solanki, P., and El-maarry, M. R.: Mafic Mineral Anomaly in the Ohm Crater of the Moon, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-5929, https://doi.org/10.5194/egusphere-egu23-5929, 2023.

14:25–14:35
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EGU23-10887
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On-site presentation
Urs Mall and Yehor Surkov

Boulders are a major surface feature on solid planets and small bodies, including asteroids and comets. Interest in these clasts range from applications relevant for landing site selection to geomechanical parameter characterization of the soil on which they rest [1], to measurements of their size frequency distributions [2] which is relevant for an understanding of their formation and erosion processes. On the Moon boulders are generally found in association with craters, hilltops, rilles, and other steep relief forms. Two main mechanisms of boulder formation are bedrock fragmentation and excavation by impacts, and progressive exposure of pre-existing blocks and fractured bedrock by removal of regolith from steep reliefs by diffusive creep.

An important issue are transport processes which can move the stones on the surface of their parent bodies. On the Moon, one group of boulders, frequently called “rolling stones”, have left tracks on the surface which can cover large distances. Mainly two mechanisms, meteoritic impact and moonquakes [3], have been cited in the literature as drivers of boulder displacements. Much less attention has been given to the hypothesis that other processes like thermal solar-induced rock breakdown [4] could deliver the initial momenta that could initiate the movement of meta stabile rocks.

From an AI -based mapping of the distribution of boulders with tracks on the lunar surface [5] we know that the majority of these boulders are found – not surprisingly - within craters. However, as the AI-based procedure strongly underestimated the number of boulders with tracks, we have conducted a new investigation to map these boulders. However, such a mapping it is only one prerequisite in understanding whether a thermally-induced breakdown could be responsible for an initial triggering of boulder movements. Boulders moving down the slopes disturb the mature regolith and move fresh lunar soil to the surface. This process should remotely be detectable through the stronger spectral features of the fresher optically immature regolith. The number of non-decayed boulders along crater walls should therefore be correlated with the strength of the absorption bands in spectra taken from those crater walls. Spectral characteristics of the refreshed crater walls are measurable through various quantities in the VIS-NIR (e.g. color ratios, etc.)

To start addressing the question to what extent a solar-induced breakdown can trigger rock movements, we have chosen lunar craters for which we have generated new boulder maps. For these craters we determine spectral characteristics and mineralogical composition based on a nonlinear spectral mixing model using M3 hyperspectral imager data from Chandrayaan-1. We are reporting the first results of spectral feature mapping for these craters and discuss the mineralogical interpretation, as well as the existence of a correlation between the number of observable boulders inside craters and identified spectral features of the regolith.

References:

[1] Filice, A., 1967, Science, 1967-06-16 156(3781): 1486-1487. [2] Ruesch, O. et al., 2022 Icarus, 387, 115200. [3] Kumar, S. et al., 2016, J. Geophys. Res. Planets, 121, 147– 179. [4] Molaro, J.L. et al., 2017, Icarus, 294, 247-261. [5] Bickel, V.T. et al., 2020, Nat Commun 11, 2862.

How to cite: Mall, U. and Surkov, Y.: Are day-night heating cycles a trigger for launching the “stones” on tour?, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-10887, https://doi.org/10.5194/egusphere-egu23-10887, 2023.

14:35–14:45
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EGU23-11166
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ECS
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On-site presentation
Andrew Wilcoski, Paul Hayne, and Margaret Landis

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’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 H­2O. 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’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° 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 (~8×1015 kg) could have been sourced from volcanic outgassing, though atmospheric escape processes also strongly control the efficacy of this mechanism.

 

[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.

How to cite: Wilcoski, A., Hayne, P., and Landis, M.: Polar Ice Accumulation from Volcanically Induced Transient Atmospheres on the Moon, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-11166, https://doi.org/10.5194/egusphere-egu23-11166, 2023.

14:45–14:55
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EGU23-3164
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ECS
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On-site presentation
Hongyi Wang and Shuo Yao

This work studies the remanent magnetization under a weak and a strong magnetic anomaly in Tranquillitatis and in Oceanus Procellarum respectively, which show similar surface ages of 3.6 Ga and 3.3 Ga. A 3D amplitude inversion is used to reconstruct the distributions of magnetization underground. Since there is no globally measured surface magneticeld for the Moon, a crustal magnetic anomaly model with grid resolution of 0.2° is used. The depth to the bottom of the magnetic source is fixed by the boundary identified by a relative criterion, which is 20% of the recovered maximum magnetization. The results show that the two anomalies have different depths to the bottom and different volumes of magnetic sources. The depth to the bottom of the magnetic carriers, which is possibly the Curie depth, is about 30 km and 50 km under Oceanus and Tranquillitatis. The volumes of the two magnetic sources are at the scale of 104 and 105 km3, respectively. The Bouguer gravity anomalies with spherical harmonics reaching 1200 degree in the two studied regions are also checked. The results supports that the magma intrusions containing different abundances of metallic iron are the most possible origins of the magnetic sources in the studied regions. Besides, the thermal states of lunar crust under the two studied maria were probably different during the acquisition process of remanent magnetization.

How to cite: Wang, H. and Yao, S.: Depths to the Bottom and Volumes of Magnetic Sources under a Weak and a Strong Lunar Magnetic Anomaly Revealed by 3D Inversion, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-3164, https://doi.org/10.5194/egusphere-egu23-3164, 2023.

Lunar Exploration and Utilisation
14:55–15:05
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EGU23-15933
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ECS
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On-site presentation
Andrea Sesta, Mauro Di Benedetto, Daniele Durante, Luciano Iess, Michael Plumaris, Paolo Racioppa, Paolo Cappuccio, Ivan di Stefano, Debora Pastina, Giovanni Boscagli, Serena Molli, Fabrizio De Marchi, Gael Cascioli, Krzysztof Sosnica, Agnes Fienga, Nicola Linty, and Jacopo Belfi

Within the pre-phase A of the Moonlight project proposed and funded by the European Space Agency (ESA), the ATLAS consortium has proposed an architecture to support a Lunar Radio Navigation System (LRNS) capable of providing PNT (Positioning, Navigation, and Timing) services to various lunar users. The Moonlight LRNS will be a powerful tool in support of the lunar exploration endeavors, both human and robotic.

The ESA LRNS will consist of a small constellation of 3-4 satellites put in Elliptical Lunar Frozen Orbits (ELFO) with the aposelene above the southern hemisphere to better cover this region, given its interest for future lunar missions. This LRNS will be supported by a ground station network of small dish antennas (~30 cm), which can establish Multiple Spacecraft Per Aperture (MSPA) tracking at K-band. Any Earth station will be capable of sending a single uplink signal to multiple spacecraft thanks to Code Division Multiplexing modulation, while in the downlink multiple carriers can share the same K-band bandwidth by implementing Code Division Multiple Access (CDMA) on the onboard transponders. This allows the implementation of the Same Beam Interferometry (SBI) technique [1], which adds to spread spectrum ranging and Doppler measurements. In the scope of disseminating accurate PNT services to end users, the constellation will also be capable of maintaining a synchronization to the Earth station clocks to the ns level.

The performances of the proposed architecture have been validated through numerical simulations performed with the ESA GODOT software, enhanced with additional user-defined features and capabilities. For each satellite of the LRNS constellation, the attainable orbital accuracy is at level of a few meters for most orbit mean anomalies and it has been computed considering a setup which includes a perturbed dynamical model (mainly coming from uncertainties in the accelerations induced by the solar radiation pressure and orbital maneuvers) and a realistic error model for Doppler, ranging and SBI measurements.

REFERENCE:

  • Gregnanin, M. et al. (2012). Same beam interferometry as a tool for the investigation of the lunar interior. Planetary and Space Science 74, 194-201

How to cite: Sesta, A., Di Benedetto, M., Durante, D., Iess, L., Plumaris, M., Racioppa, P., Cappuccio, P., di Stefano, I., Pastina, D., Boscagli, G., Molli, S., De Marchi, F., Cascioli, G., Sosnica, K., Fienga, A., Linty, N., and Belfi, J.: Orbit Determination and Time Transfer for a Lunar Radio Navigation System, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-15933, https://doi.org/10.5194/egusphere-egu23-15933, 2023.

15:05–15:15
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EGU23-10737
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ECS
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On-site presentation
Mehmet Ogut, Shannon Brown, Alan Tanner, Sidharth Misra, Chris Ruf, Chi-Chih Chen, and Matthew Siegler

The lunar heat-flow ultra-wideband spectrometer operates over an extended frequency band from 300 MHz to 6.0 GHz. It is a direct-acquisition single-chain digital spectrometer measuring 1024 spectral channels over 6 GHz bandwidth with each channel bandwidth about 6 MHz. The LHR instrument is intended to characterize the near surface regolith thermal and dielectric properties in order to determine the local geothermal heat flux. It would also reveal subsurface thermal and dielectric property changes due to buried ice, dielectric materials like ilmenite, and bedrock. The wide spectral bandwidth is expected to provide up to 1 m deep brightness temperature measurements from as close as 5 cm penetration depth at higher frequency end of the spectra. Using information obtained at multiple frequency bands, the subsurface temperatures and dielectric properties can be reconstructed.

 

The instrument is currently being developed at Jet Propulsion Laboratory in Pasadena, CA. The design includes a novel receiver architecture allowing a single chain design for the ultra-wideband channelized spectral operation for enabling the science objectives of the instrument. The lab-bench demonstration of the lunar spectro-radiometer has been performed including the calibration testing. The environmental testing will be further conducted before proceeding with the flight model. The final flight version of the spectro-radiometer instrument is expected to have light weight, low-power and small-size suitable for a deployment into a lunar rover or lander.

 

 

How to cite: Ogut, M., Brown, S., Tanner, A., Misra, S., Ruf, C., Chen, C.-C., and Siegler, M.: An Ultra-Wideband Spectrometer for Lunar Heat-Flow Measurements, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-10737, https://doi.org/10.5194/egusphere-egu23-10737, 2023.

15:15–15:25
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EGU23-13387
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ECS
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On-site presentation
Peter Keresztes Schmidt, Matthias Blaukovitsch, Nikita J. Boeren, Marek Tulej, Andreas Riedo, and Peter Wurz

With NASA’s increased focus on exploration of our Moon within the Artemis program, new scientific goals have been formulated to expand our knowledge on the history of our Solar System, including the evolution of the Earth-Moon system. Additionally, establishing a permanent human presence on the Moon has been declared a goal of the Artemis program, the success of which will inevitably depend on in-situ resource utilization (ISRU) of lunar material. In turn, successful ISRU requires methods capable of analysing and selecting suitable materials in place. To support these tasks, sensitive instrumentation capable of determining the elemental and isotope composition of geological samples from the lunar surface is essential. Consequently, defining and determining the technical requirements of such instrumentation, constructing it accordingly, and verifying its performance are all crucial steps in maximising the scientific return of such a mission. Furthermore, NASA’s Artemis program also aims to facilitate future human exploration of Mars, which implies that instrumentation applied successfully on the Moon might find its application on the Martian surface in the future.

 

We present our progress in designing, constructing and testing a prototype miniature laser ablation ionisation mass spectrometer (LIMS) for in-situ measurements on the lunar surface. The finalised instrument will be deployed on the Commercial Lunar Payload Service (CLPS) mission CP-22 scheduled for launch in late 2026 and land in the lunar south pole region. Our miniature reflectron-type time-of-flight mass analyser (160 mm x Ø 60 mm) designed for in-situ space applications was coupled to a pulsed Nd:YAG microchip laser system (SB1 series, Bright Microlaser Srl, Italy) operating at 532 nm (max. laser pulse energy of 40 µJ, pulse repetition rate of 100 Hz). The laser source and the optics were mounted colinearly to the optical axis of the instrument assembly into a cage system. This construction is modelled after the envisioned flight design, and therefore used to determine the required optical and electronic performance characteristics of the future flight instrument. The current flight design will be presented as well. Furthermore, validation of the technical implementation and verification of the scientific requirements will be discussed through the results of laser ablation experiments conducted on lunar regolith simulant.

How to cite: Keresztes Schmidt, P., Blaukovitsch, M., Boeren, N. J., Tulej, M., Riedo, A., and Wurz, P.: Instrumentation for laser ablation ionisation mass spectrometry on the lunar surface, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-13387, https://doi.org/10.5194/egusphere-egu23-13387, 2023.

15:25–15:35
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EGU23-10526
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ECS
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On-site presentation
Sarah Vines, George Ho, David Blewett, Jasper Halekas, Benjamin Greenhagen, Brian Anderson, Dany Waller, Jörg-Micha Jahn, Peter Kollmann, Brett Denevi, Heather Meyer, Rachel Klima, Joshua Cahill, Lon Hood, Sonia Tikoo, Xiao-Duan Zou, Mark Weiczorek, Myriam Lemelin, Shahab Fatemi, and Edward Cloutis

Lunar Vertex is a mission at the intersection of multiple science communities, from planetary geology to space plasma physics. As the first Payloads and Research Investigations on the Surface of the Moon (PRISM1) investigation, scheduled for delivery to the Reiner Gamma (RG) magnetic anomaly in 2024 aboard a commercial lunar lander, Lunar Vertex will unravel the nature of the RG anomaly, the connection to and origin of the associated lunar swirl surface feature, and the structure and impact of the “mini-magnetosphere” in this region. Lunar Vertex includes a suite of magnetometers (Vector Magnetometer – Lander; VML), a fixed-mounted set of cameras (Vertex Camera Array; VCA), and a low-energy ion and electron plasma analyzer (Magnetic Anomaly Plasma Spectrometer; MAPS) on the lander. In addition, a second suite of commercial fluxgate magnetometers (Vector Magnetometer – Rover; VMR) and a multispectral imager (Rover Multispectral Microscope; RMM) are mounted on a dedicated rover that will traverse a distance of at least 500 m from the lander, providing additional multi-point measurements. The combination of magnetic field measurements taken during cruise and descent by VML and during surface operations by both VML and VMR will characterize the surface magnetic field within a strong lunar magnetic anomaly. The combined magnetic field and plasma measurements from VML and MAPS will provide direct observations of plasma populations reaching the lunar surface and the associated local magnetic field configuration. Furthermore, the lunar regolith within the RG magnetic anomaly and over different regions of the associated lunar swirl will be characterized by RMM and VCA to reveal the surface texture, composition, and particle distribution around both the lander and rover locations and the correspondence to potential surface weathering processes.

How to cite: Vines, S., Ho, G., Blewett, D., Halekas, J., Greenhagen, B., Anderson, B., Waller, D., Jahn, J.-M., Kollmann, P., Denevi, B., Meyer, H., Klima, R., Cahill, J., Hood, L., Tikoo, S., Zou, X.-D., Weiczorek, M., Lemelin, M., Fatemi, S., and Cloutis, E.: Lunar Vertex: A PRISM Science Investigation of the Reiner Gamma Lunar Magnetic Anomaly and Swirl, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-10526, https://doi.org/10.5194/egusphere-egu23-10526, 2023.

15:35–15:45
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EGU23-5040
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On-site presentation
Martin Knapmeyer, Brigitte Knapmeyer-Endrun, Michael Maibaum, Jens Biele, Cinzia Fantinati, Oliver Küchemann, Stephan Ulamec, and Jean-Pierre de Vera

Recently, NASA’s InSight mission has shown the value of geophysical landers by greatly increasing our knowledge of the interior of Mars. Correspondingly, geophysical experiments are also of great relevance to lunar exploration: a number of geophysical experiments were proposed in response to the ESA's 2020 call for ideas for a scientific utilization of the large logistics lander (Argonaut). Geophysical payloads are already planned for the Moon, e.g. the Farside Seismic Suite will land a broad-band seismometer in 2025. We here present how the LUNA Habitat training facility under construction in Cologne, Germany, can contribute to the development and testing of lunar geophysical instrumentation.

The about 700 square meters of the LUNA Habitat will be covered by 60 cm of EAC-1 regolith simulant on most of the area. On an area of 140 square meters, regolith depth increases to 3 m along a sloping bottom (25° and 40°). This part of LUNA provides an invisible, but explorable underground structure suitable for seismic profiling, ground penetrating radar, geoelectrics, geomagnetics and other techniques, as well as sufficient depth for drilling, subsurface sampling, and deployment of heat flow probes. Sculpting craters and even caves in the regolith, as well as cooling small portions of it, is envisioned. Support by the facility will include personnel with experience in geophysical measurements and data analysis, an end-to-end operational environment including a remote control center with standard communication technology, and, last but not least, training of astronauts in co-operation with robotic units to operate the equipment in lunar surface suits and under gravity offloading.

A four-element, Y-shaped array of short period seismometers, based on the layout of the Apollo 17 seismic experiment, will be deployed on the LUNA construction site before erecting the building to record seismic noise sources (car traffic on the DLR campus, the ENVIHAB short arm centrifuge, wind tunnel discharges, air traffic on the nearby CGN international airport etc.). It will also allow for ambient noise analysis aimed at the underground structure, which is expected to consist of Rhine sediments. An active refraction seismic experiment and the deployment of 12 nodal sensors will further aid in site characterization. LUNA will have a concrete floor of up to 60 cm thickness, but with a structured underside for static reasons. The array will be re-deployed on the concrete once the hall is erected to characterize in how far the new high-velocity layer hides the underlying sediments from seismic observation. After completion of LUNA, the effect of the regolith cover on seismic recordings will be characterized by a third array deployment. Documentation of construction details, especially steel enforcing in the concrete, is foreseen.  A broad-band seismometer will be installed in the LUNA Habitat permanently, once construction is finished, to support the identification of artificial noise sources and local seismicity in the recordings of customer instruments, and monitor possible changes in the background e.g. due to new buildings or other large-scale research facilities on the DLR campus.

How to cite: Knapmeyer, M., Knapmeyer-Endrun, B., Maibaum, M., Biele, J., Fantinati, C., Küchemann, O., Ulamec, S., and de Vera, J.-P.: The ESA/DLR LUNA Habitat as geophysical experimentation facility, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-5040, https://doi.org/10.5194/egusphere-egu23-5040, 2023.

Posters on site: Tue, 25 Apr, 16:15–18:00 | Hall X4

Chairpersons: Chrysa Avdellidou, Bernard Foing
X4.344
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EGU23-10755
Christopher Watson, Thayyil Jayachandran, Anton Kascheyev, David Themens, Richard Langley, Richard Marchand, and Andrew Yau

The lunar ionosphere is a ~100 km thick layer of electrically charged plasma surrounding the moon.  Despite knowledge of its existence for decades, the structure and dynamics of the lunar plasma remain a mystery due to lack of consistent observational capacity. An enhanced observational picture of the lunar ionosphere and improved understanding of its formation/loss mechanisms is critical for understanding the lunar environment as a whole and assessing potential safety and economic hazards associated with lunar exploration and habitation. To address the high priority need for observations of the electrically charged constituents near the lunar surface, we introduce a concept study for the Radio Instrument Package for Lunar Ionospheric Observation (RIPLIO). RIPLIO would consist of a multi-CubeSat constellation (at least two satellites) in lunar orbit for the purpose of conducting “crosslink” radio occultation measurements of the lunar ionosphere, with at least one satellite carrying a very high frequency (VHF) transmitter broadcasting at multiple frequencies, and at least one satellite flying a broadband receiver to monitor transmitting satellites. Radio occultations intermittently occur when satellite-to-satellite signals cross through the lunar ionosphere, and the resulting phase perturbations of VHF signals may be analyzed to infer the ionosphere electron content and high- resolution vertical electron density profiles. As demonstrated in this study, RIPLIO would provide a novel means for lunar observation, with the potential to provide long-term, high-resolution observations of the lunar ionosphere with unprecedented pan-lunar detail.

How to cite: Watson, C., Jayachandran, T., Kascheyev, A., Themens, D., Langley, R., Marchand, R., and Yau, A.: Radio Instrument Package for Lunar Ionospheric Observation: A Concept Study, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-10755, https://doi.org/10.5194/egusphere-egu23-10755, 2023.

X4.345
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EGU23-15759
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ECS
Laura Rubino, Alejandro Remujo Castro, Ubaldo Denni, Marco Muccino, Lorenzo Salvatori, Mattia Tibuzzi, Matteo Petrassi, Michele Montanari, Marco Traini, Luciana Filomena, Lorenza Mauro, Luca Porcelli, and Simone Dell'Agnello

Laser Ranging is a technique used to perform accurate precision distance measurements between a laser ground station and an optical target, a Cube Corner Retroreflector (CCR). Since 1969 it is possible to realize Lunar Laser Ranging (LLR) measurements thanks to Apollo and Luna missions that placed some arrays of CCRs on the lunar surface. LLR outputs include accurate tests of General Relativity, information of the composition of the Moon, its ephemerides and its internal structure or geocentric positions and motions of ground stations: research uniquely enabled by the Moon.

Despite laser ground stations have significantly improved during the years, the current limitation of the lunar optical target is due to lunar librations. In order to achieve more precise LLR measurements, MoonLIGHT project is designed by SCF_Lab joined UMD. The aim of the project is designing a next-generation of retroreflectors, prototyping, manufacturing and qualify them for the Moon’s environment. Moving from a multi small CCRs array to a single large 100 mm CCR, called MoonLIGHT, unaffected by the lunar librations.

The field of view of each CCR is limited: the retroreflector needs to be pointed precisely to the ground station. The Apollo CCR arrays were manually arranged by the astronauts. In 2018 INFN proposed to ESA the MoonLIGHT Pointing Actuators (MPAc) project, able to perform unmanned pointing operation of MoonLIGHT. In 2019 ESA chose MPAc among 135 eligible scientific project proposals. In 2021 ESA agreed with NASA to launch MPAc to the Reiner Gamma region of the Moon, with a Commercial Lunar Payload Services (CLPS), which is part of the Artemis program. The lander on which MPAc will be integrated is designed by Intuitive Machines (IM). The launch expected date is in April 2024.

MPAc must be able to perform two continuous perpendicular rotations to accurately point the frontal face of the CCR towards the Earth. The device is continuously evolving to ensure the success of the mission, that will take place in Ultra High Vacuum space conditions, in a wide operating temperature range. Terrestrial prototypes, with all the characteristics of the final structure, have been developed for the study of mechanical and electronics components. Qualification tests for space are being planned as the components for the Proto Flight Model (PFM) arrived to the LNF. Payload delivery is scheduled for August 2023.

MPAc will contribute to attain lunar orbit range accuracy below few mm. This will improve, in turn, the precision of the Parametrized Post-Newtonian (PPN) parameters and put more stringent constraints on departures from GR predictions with observations.

How to cite: Rubino, L., Remujo Castro, A., Denni, U., Muccino, M., Salvatori, L., Tibuzzi, M., Petrassi, M., Montanari, M., Traini, M., Filomena, L., Mauro, L., Porcelli, L., and Dell'Agnello, S.: The MoonLIGHT Pointing Actuator (MPAc) project, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-15759, https://doi.org/10.5194/egusphere-egu23-15759, 2023.

X4.346
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EGU23-13668
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ECS
Stefanie Hempel, Martin Knapmeyer, Jens Biele, and Hans-Herbert Fischer

As international efforts to return humans to the Moon are increasing, ESA's European Astronaut Center (EAC) and the German Aerospace Center (DLR) are expanding their facilities by the LUNA habitat providing a 700m²-wide testbed covered by 60cm lunar regolith simulant (EAC-1) for astronaut training, including deploying and operating geological and seismic regolith characterization experiments, In Site Resource Utilization technologies (ISRU), biological and chemical experiments by both telerobotic and human activity. The LUNA facility will be operated as collaboration between ESA and DLR's Microgravity User Support Center (MUSC, see also the presentation by Knapmeyer et al. at this conference).

Geophysical experiments have proven useful to investigate the subsurface structure at the landing sites of e.g. Apollo and Chang'e missions on the Moon, but also at the InSight landing site on Mars, and a seismometer experiment to the lunar far side is already scheduled (Far Side Seismic suite, in 2025). To support future geophysical investigations on the Moon, a first seismic experiment was conducted in June, 2018 at the previously envisioned site of the LUNA facility between the :envihab, a research facility of the Institute for Aerospace Medicine and the European Astronaut Center (EAC) at Cologne-Porz. This passive seismic experiment consisted of a four-element, Y-shaped array of short period seismometers, based on the layout of the Apollo 17 seismic experiment. It recorded regional seismicity as well as urban noise. These measurements will be repeated and expanded by an active seismic refraction experiment at the new construction site just south of the EAC - before, during and after the construction of the facility, before and after the installment of the regolith cover to investigate the impact of the LUNA facility on the data quality and coupling to the ground.

We present details of the 2018 experiment as well as preliminary results, analyzing ambient noise to map the dominant sources of urban noise such as car traffic and airplane traffic at the nearby CGN international airport, the operational noises of the :envihab centrifuge and the wind tunnel as well as nearby construction and drilling.

How to cite: Hempel, S., Knapmeyer, M., Biele, J., and Fischer, H.-H.: Urban seismic noise investigation at the site of ESA/DLR’s future LUNA facility at Cologne, Germany, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-13668, https://doi.org/10.5194/egusphere-egu23-13668, 2023.

X4.347
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EGU23-17528
Bernard Foing, Henk Rogers, Serena Crotti, and Jara Pascual and the ILEWG LUNEX EuroMoonMars Team and EuroSpaceHub Academy

EuroMoonMars programme in Data Analysis, Instrumentation, Field Work and Astronautics: EuroMoonMars is an ILEWG programme [1-226] in collaboration with space agencies, academia, universities and research institutions and industries. The programme includes research activities for data analysis, instruments tests and development, field tests in MoonMars analogue, pilot projects , training and hands-on workshops , and outreach activities. Extreme environments on Earth often provide similar terrain conditions to sites on the Moon and Mars. In order to maximize scientific return it becomes more important to rehearse mission operations in the field and through simulations. EuroMoonMars field campaigns have then been organised in specific locations of technical, scientific and exploration interest. Lunex EuroMoonMars, has been organizing in collaboration with ESA, NASA, European and US universities a programme of data analysis, instrumentation tests, field work and analog missions for students and researchers in different locations worldwide since 2009, including Hawaii HI-SEAs, Utah MDRS, Iceland, Etna/ Vulcano Italy, Atacama, AATC Poland, ESTEC Netherlands, Eifel Germany, etc… Analogue missions provide a practical ground in which students can test the notions learnt at the university in a realistic simulation context. Over the course of these missions, students have access to special Space instrumentation, laboratories, Facilities, Science Operations, Human Robotic partnerships. In 2023 , EuroMoonMars and EuroSpaceHub Academy co-sponsored a series of EMMPOL Moonbase isolation simulation campaigns in Poland.

EuroSpaceHub programme for Space Innovation Workforce Development: The EuroSpaceHub project to facilitate accessibility to the Aerospace sector. EuroSpaceHub is a European-led project with collaborators worldwide, funded by the EIT HEI initiative - Innovation Capacity Building for Higher Education – with Agenda 2021-2027. The project includes six  core partners: Vilnius TU, ISU, U C Madrid,  Sikorsky Kyiv, Collabwith and Lunex. The project was created to foster collaboration, innovation and entrepreneurship in the European Aerospace sector. EuroSpaceHub Academy develops training programme for Space researchers and entrepreneurs.

Space Engineering Workforce Development: we have also developed a semester course of Space System Design Engineering at  EPFL Lausanne sicne 2020.

Interdisciplinary Space Workforce Development: In the frame of ISU International Space University and EuroSpaceHub academy, we performed lectures,  hands-on workshops including the operations of instruments on EuroMoonMars ExoGeoLab lander, workshops on MoonOutpost design performed in the frame of MSS master , or SSP Space Studies Programme. Together with ISU , EuroSpaceHub staff co-supervised various IP Individual Projects of students, and Master Research Projects.

EuroSpaceHub Participation to Congress and Events: We also co-sponsored the participation to conferences such as LPSC, EGU, IAC and the organization of events or workshops connecting the space scientists, engineers, innovators, entrepreneurs to space stakeholders. This included talks and expo booths at IAC International Astronautical Congress and Rome New Space Economy Forum.

How to cite: Foing, B., Rogers, H., Crotti, S., and Pascual, J. and the ILEWG LUNEX EuroMoonMars Team and EuroSpaceHub Academy: ILEWG/LUNEX EuroMoonMars & EuroSpaceHub Academy: Recent Highlights, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-17528, https://doi.org/10.5194/egusphere-egu23-17528, 2023.

X4.348
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EGU23-969
Emily Law and Brian Day and the Solar System Treks

NASA’s Moon Trek (https://trek.nasa.gov/moon/) is one of a growing number of interactive, browser-based, online portals for planetary data visualization and analysis produced by NASA’s Solar System Treks Project (SSTP). Moon Trek continues to be enhanced with new data and new capabilities enabling it to facilitate the planning and conducting of upcoming lunar missions by NASA, its commercial partners, and its international partners, as well as scientific research.

Moon Trek’s innovation visualization and analysis tools are already being used by a growing number of missions and scientists around the world. The tools deployed including interactive 2D and 3D visualization, a DEM and Ortho Mosaic Image production pipeline as well as tools for distance measurement, elevation profile generation, solar altitude and azimuth calculation, 3D print file generation, virtual reality visualization generation, lighting analysis, electrostatic surface potential analysis, slope analysis, rock detection, crater detection, rockfall detection, and profiling of raster data.

Moon Trek has added a new set of visualization and analysis tools include line of sight analysis (facilitating communications planning and detailed studies of solar illumination), traverse path planning, and 3D traverse path visualization tool, among others. This presentation for EGU will highlight Moon Trek’s latest tools and demonstrate their usage targeted for Lunar mission planning and exploration in this exciting Artemis era.

How to cite: Law, E. and Day, B. and the Solar System Treks: Lunar Mission Planning and Exploration using NASA’s Moon Trek Portal, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-969, https://doi.org/10.5194/egusphere-egu23-969, 2023.

X4.349
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EGU23-3992
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Kelsi Singer, Helle Skjetne, Julie Stopar, Mikayla Huffman, Clark Chapman, Lillian Ostrach, Brad Jolliff, and William McKinnon

We have performed an extensive study of secondary craters associated with specific primary craters on the Moon.  These data can be used to understand aspects of both (1) the secondary craters themselves and (2) the ejecta fragments that formed them.  Studying ejecta and secondary craters are a part of understanding the overall contributions of impacts to shaping and redistributing material across the lunar surface. 

We produced secondary crater size-range distributions for a large range of primary crater sizes (~0.8-660 km dimeter primaries).  Our results can be used to make a map of estimated maximum secondary crater sizes across the Moon.  They can also be used to test if a specific secondary crater cluster is likely related to a given primary crater.   

We also produced ejecta fragment size-velocity distributions for all our study sites.  These results can be used to understand the size and velocity of the ejecta fragments that were ejected as part of the primary impact.  This helps us understand the dynamics of the primary impact and the formation of fragments (or clusters of fragments) and how they are ejected during the passage of the shock wave through a planetary surface.  This new empirical data can be used to help constrain analytical and numerical models of dynamic fragmentation, place constraints on the largest ejecta fragments expected be ejected at escape velocity from the Moon, and used as inputs into models of regolith development and impact gardening. 

We will present the most current results on the above topics.  Initial results for 6 primary craters are presented in Singer et al. 2020 where we discovered a previously unrecognized trend where the size velocity distributions are dependent on the size of the impact (i.e., scale dependent).  We now have data on 10 additional primaries and further applications of the study. 

Singer, K. N., Jolliff, B. L., & McKinnon, W. B. (2020). Lunar secondary craters and estimated ejecta block sizes reveal a scale-dependent fragmentation trend. J. Geophys. Res., 125(8), e2019JE006313. doi:10.1029/2019JE006313

How to cite: Singer, K., Skjetne, H., Stopar, J., Huffman, M., Chapman, C., Ostrach, L., Jolliff, B., and McKinnon, W.: Lunar secondary crater distributions and ejecta fragment size velocity distributions: implications for regolith redistribution, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-3992, https://doi.org/10.5194/egusphere-egu23-3992, 2023.

X4.350
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EGU23-14255
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ECS
Rachael Martina Marshal, Ottaviano Rüsch, Christian Wöhler, Kay Wohlfarth, Sergey Velichko, and Markus Patzek

Introduction and Methods:  Our understanding of the response of boulders to space weathering, micrometeorite abrasion, thermal fatigue, and consequently their evolution into regolith can be improved by characterizing the surface roughness of the uppermost layer of boulders. In the first phase of our study [1] we characterize the surface roughness of boulder fields photometrically by using the phase ratio methodology applied to orbital image data. In the second phase of our study (in-progress) we focus on characterizing the sub-mm scale topography and roughness of naturally fresh surfaces of meteorite samples. The photometric roughness of boulder fields on the lunar surface is studied by employing a normalized logarithmic phase ratio difference (NLPRD) metric, described in [1], to measure and compare the slope of the phase curve (reflectance versus phase angle) of a rock-rich field to a rock-free field . We compare the photometric roughness of rock-rich fields on simulated images, with the photometric roughness of rock-rich fields on Lunar Reconnaissance Orbiter Narrow Angle Camera (LROC NAC) images sampled around an Unnamed crater at Hertzsprung S.


Results and Discussion: The NLPRD is normalized to a rock-free reference surface, assuming the roughness of the regolith within the boulderfield is comparable to the roughness of the regolith at the rock-free reference regions, the higher roughness of the boulder-fields implies the presence of rocks with diverse sub-mm scale roughness and, possibly, variable single scattering albedo. In figure 1b, the spread in NLPRD values for different rock morphologies, is exceeded by the spread in  NLPRD of the NAC-resolved boulderfields. We find spatial clustering of photometrically smooth and rough boulderfields in the downrange and up-range respectively of the Unnamed crater at Hertzsprung S, reflecting ejecta asymmetry (in agreement with [2]) and possibly indicating asymmetric modification of ejecta rock surfaces during impact excavation process. Our results imply that rock physical properties at the start of the surface exposure period are a function of petrology as well as the (shock) effects imparted upon ejecta rock formation and excavation. The work-in progress deals with supplementing our findings with investigation of the sub-mm scale topography and roughness of meteorite and lunar samples. To study the sub-mm scale roughness of these samples we produce high-resolution DTMs at the µm scale using a non-contact optical profilometer. A sample high-resolution DTM of lunar breccia NWA11273 is shown in figure 2.



Figure 3 shows that variations of the mean slope with spatial scale exists within different meteorites types. Next, we will investigate the scale-dependent rock micro-texture of various samples (i.e., ordinary and carbonaceous chondrites, lunar basalts and breccias as well as meteorites from the HED clan), and provide typical values of surface roughness that will inform photometric modelling of rock surfaces.

References: [1] Marshal, R. M., Rüsch, O., Wöhler, C., Wohlfarth, K., & Velichko, S. (2022). Icarus, 115419 [2] Velichko, S., Korokhin, V., Velikodsky, Y., Kaydash, V., Shkuratov, Y., & Videen, G. (2020). PSS, 193.

How to cite: Marshal, R. M., Rüsch, O., Wöhler, C., Wohlfarth, K., Velichko, S., and Patzek, M.: Photometry of rock-rich surfaces on airless bodies., EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-14255, https://doi.org/10.5194/egusphere-egu23-14255, 2023.

X4.351
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EGU23-7979
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ECS
Kamilla Cziráki and Gábor Timár

Because the Moon is much less flattened than the Earth, most lunar GIS applications use a spherical datum. However, nowadays, with the renaissance of lunar missions approaching, it seems worthwhile to define an ellipsoid of revolution that better fits the lunar gravity potential surface. The main long-term benefit of this might be to make the lunar adaptation of methods already implemented in terrestrial GNSS, gravimetry and GPS applications easier and somewhat more accurate.

In our work, we used a 660th degree and order potential surface called GRGM 1200A Lunar Geoid, developed in the frame of the GRAIL project. Samples were taken from the potential surface along a mesh that represents equal area pieces of the surface. The method of point grid selection was provided by a relatively simple Fibonacci sphere. We tried Fibonacci spheres with 100, 1000, 3000, 5000, 10000 and 100000 points and also separately examined the effect of rotating the network by length for a given number of points on the estimated parameters, but these differences was only noticeable for the lower resolution networks.

We estimated the best-fitting rotation ellipsoid semi-major axis and flatness data for the selenoid undulation values at the network points, which were obtained for a=1,737,576.6 m and f=0.000305. This parameter pair is already obtained for a 10000 point grid, while the case of reducing the points of the equidistant grid to 3000 does not cause a deviation in the axis data of more than 10 centimetres. As expected, the absolute value of the selenoid undulations has decreased compared to the values taken with respect to the spherical basal surface, with maxima exceeding +400 m still being found for Mare Serenitatis and Mare Imbrium, and the largest negative values for South Pole Aitken and Mare Orientale.

Supported by the ÚNKP-22-6 New National Excellence Program of the Ministry for Culture and Innovation from the source of the National Research, Development and Innovation Fund.

How to cite: Cziráki, K. and Timár, G.: Estimation of the parameters of a lunar ellipsoid of revolution based on GRAIL selenoid data and Fibonacci mesh, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-7979, https://doi.org/10.5194/egusphere-egu23-7979, 2023.

X4.352
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EGU23-13471
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ECS
Yuequn Lou, Xudong Gu, Xing Cao, Mingyu Wu, Sudong Xiao, Guoqiang Wang, Binbin Ni, and Tielong Zhang

Like 1 Hz waves occurring in the upstream of various celestial bodies in the solar system, 1 Hz narrowband whistler-mode waves are often observed around the Moon. However, the wave properties have not been thoroughly investigated, which makes it difficult to proclaim the generation mechanism of the waves. Using 5.5-year wave data from ARTEMIS, we perform a detailed investigation of 1 Hz waves in the near lunar space. The amplitude of lunar 1 Hz waves is generally 0.05-0.1 nT. In the GSE coordinates, the waves show no significant regional differentiation pattern but an absence inside the magnetosphere. Correspondingly, in the SSE coordinates, they can occur extensively at ~1.1-12 RL, while few events observed in the lunar wake due to a lack of interaction with the solar wind. Furthermore, the wave distributions exhibit modest day-night and dawn-dusk asymmetries, but less apparent north-south asymmetry. Compared with nightside, more intense waves with lower peak wave frequency are present on the dayside. The preferential distribution of 1 Hz waves exhibits a moderate correlation with strong magnetic anomalies. The waves propagate primarily at wave normal angles < 60° with an ellipticity of [-0.8, -0.3]. For stronger wave amplitudes and lower latitudes, 1 Hz waves generally have smaller wave normal angles and become more left-hand circularly polarized. Owing to the unique interaction between the Moon and solar wind, our statistical results might provide new insights into the generation mechanism(s) of 1 Hz waves in planetary plasma environments and promote the understanding of lunar plasma dynamics.

How to cite: Lou, Y., Gu, X., Cao, X., Wu, M., Xiao, S., Wang, G., Ni, B., and Zhang, T.: Statistical Analysis of Lunar 1 Hz Waves Using ARTEMIS Observations, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-13471, https://doi.org/10.5194/egusphere-egu23-13471, 2023.

X4.353
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EGU23-16681
Yohei Miyake and Jin Nakazono

Mission preparation for lunar exploration using landers has been rapidly increasing, and strong demand should arise toward precise understanding of the electrostatic environment. The lunar surface, which has neither a dense atmosphere nor a global magnetic field, gets charged electrically by the collection of surrounding charged particles of the solar wind or the Earth's magnetosphere. As a result of the charging processes, the surface regolith particles behave as "charged dust grains". Dust particles have been suggested to have adverse effects on exploration instruments and living organisms during the lunar landing missions, and their safety evaluation is an issue to be solved for the realization of sustainable manned lunar explorations. It is necessary to develop comprehensive and organized understanding of lunar charging phenomena and the electrodynamic characteristics of charged dust particles.

It is widely accepted that the surface potential of the lunar dayside is, "on average" several to 10 V positive due to photoelectron emission in addition to the solar wind plasma precipitation. Recent studies, however, have shown that insulating and rugged surfaces of the Moon tend to make positive and negative charges separated and irregularly distributed, and intense and structured electric fields can be formed around them. This strong electric field lies in the innermost part of the photoelectron sheath and may contribute to mobilizations of the charged dust particles. Since this strong electric field develops on a spatial scale of less than the Debye length and can take various states depending on the lunar surface geometry, it is necessary to update the research approach. In this paper, we will discuss the direction of the near-surface plasma, electrostatic, and dust environment for upcoming lunar landing missions.

How to cite: Miyake, Y. and Nakazono, J.: Lunar plasma and electrostatic environment: numerical approach and its future prospects, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-16681, https://doi.org/10.5194/egusphere-egu23-16681, 2023.

Posters virtual: Tue, 25 Apr, 16:15–18:00 | vHall ST/PS

Chairpersons: Chrysa Avdellidou, Bernard Foing
vSP.9
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EGU23-3206
Bojing Zhu

The planetary magnetic field, caused by convective currents in the cores and linking thermal and interior, is a fundamental way to determine the angular momentum exchange and secular variation in the core motions & core-mantle coupling system. But understanding the high temperature-pressure (e.g., ~5000 °C, 135~330 Gigapascals) rheology fluid flows in planetary cores is a tremendous interdisciplinary challenge. The fine-structure investigation requires understanding the fundamental rheology fluid dynamic involving turbulence and rotation from continuing hydro-dynamo-kinetic coupling scales well beyond the present traditional partial differential equation virtual test.

The lunar magnetic field is believed not currently to possess a feeble global magnetic field and can be ignored when exploring the solar-flare CME-induced solar storm transplant on the lunar surface. The hypothesis holds that the crustal magnetizations were acquired early in lunar history when dynamics were still operating. At that time, the dynamo magnetic fields were generated by the thermochemical convection of electrically conductive alloy metal liquid within lunar cores and reduced with the convection cooling process. The turbulence mechanical stirring of lunar core rheology fluids and perturbations by the tidal effect and orbital precession can contribute to sustaining dynamo fields.

With the supporting observations of China’s lunar and deep space exploration in recent years, it has become possible to re-estimates the past magnetic field by considering combining the tidal heating induced dissipation from viscous friction associated with the differential procession at a different angle and dynamo action (the non-ideal plasma; inner core-outer core-mantle; warm dense matter; liquid iron alloy; chemical-geological properties; density-temperature-pressure) together again.

In this work, based on the newly developed optimization methodology and numerical algorithm of relativistic hybrid particle-in-cell and lattice Boltzmann (RHPIC-LBM version 1.1.2), we establish the 3D lunular magnetic field modeling with combined rheology dynamo thermally and tidal-heating of its lunar cores and investigate the history of magnetic field evolution; And figure out the effect of tidal heating in the deepest lunar mantle,  and offer a possible unprecedented window on this intermediate state of rheology matter and providing a new virtual testing ground for dense rheology plasma theories.

How to cite: Zhu, B.: Exploration of Lunar magnetic fields with dynamo thermally and tidal heating-driven rheology model, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-3206, https://doi.org/10.5194/egusphere-egu23-3206, 2023.