AstroLEAP: A Surface Package to Monitor the Near-Surface Lunar Environment

Introduction: The lunar surface has become a major target for a number of Space Agencies and private stakeholders with a number of commercial and institutional missions under preparation, relying on both robotic deployments and astronaut based operations. Future ESA lunar missions of interest include ArgoNET and MoonLight enabling the implementation of a lunar communication and navigation network, as well as the delivery of payloads of different nature and at different location to the lunar surface. In this highly evolving international context as part of ESA’s strategic vision for sustained human and robotic exploration of the Moon and beyond [1-2] and the evolving NASA Artemis program [e.g., 3], the deployment of a Lunar Environment Analysis Package (AstroLEAP) becomes necessary to characterize the lunar surface near environment and help both in the design of upcoming missions and contribute to real time feedback on lunar surface environmental conditions for plasma, fields, lunar dust and radiation.

AstroLEAP Scope: As such, AstroLEAP eventually aims to provide in-situ measurements of near surface plasma populations, electro-magnetic fields, transported lunar dust and ejecta, as well as incoming meteoritic flux, exospheric species and surface radiation. Such measurements will help to characterise the associated physical mechanisms acting at the surface [e.g., 4-10] to provide environmental data and help constrain exploration environment models addressing both fundamental scientific questions and preparation for safe and sustained lunar surface operations [1,2,11, 12] (Figure 1).

In particular, AstroLEAP takes advantage of the Moon as a unique vantage point to characterise the upstream solar wind and Earth magnetosphere environments variations along the lunar orbit. A key design driver for the analysis package is the requirement for long duration (1-5 years) in situ surface operations, to understand the impact of temporally variable conditions on the environment dynamics, e.g., over several lunations, varying solar illumination, varying solar wind flux (including solar activity and solar events such as SEPs and CMEs), magnetosheath and tail variability, plasmasheet crossings; meteoroid impacts, etc. [4-10].

Science Definition:  The AstroLEAP facility will  be composed of an analytical instrument suite supported by a payload servicing module (in preparation by ESA) providing long-term power, communications, power conversion and data storage/transfer (Figure 2). The initial science case informing AstroLEAP development studies was elaborated as a result of an international Facility Definition Team (FDT) [12]. Exploration science questions have been formulated and categorized within a number of key themes that encompass ESA strategic documents [1,2] and international exploration goals [e.g., 3,11], including:

• Near surface plasma, particles and fields
• Earth Magnetospheric Environments
• Energetic particle Environment
• Surface bounded Exosphere
• Dust Environment
• Human exploration Impact

Resultant synergistic exploration-enabling and exploration-enabled science objectives have been flown to a science traceability matrix, which describes measurements requirements, deployment and functional requirements (pointing, sampling, etc.). Target science products, performance and associated example analytical techniques/instrumentation that can be applied to addressing the identified measurements have also been defined.

Ongoing Development: This presentation will provide an overview of the AstroLEAP science goals and measurements objectives as well as potential instrumentation of interest and to engage the community in discussing those in the current context. It will also elaborate on challenges regarding implementation due to intrinsic lunar surface environment constraints and possible operational constraints in relation to an ongoing Phase A development study. 

[1] ESA Explore 2040 https://www.esa.int/About_Us/ESA_Strategy_2040 [2] ESA Strategy for Science at the Moon (2019); [3] Artemis III SDT Report (2021); [4]  Dandouras, I. et al. (2023) Front. Astron. Space Sci., 10: 1120302 ; [5] Grün, E. et al. (2011) PSS, 59, 1672-1680 ; [6] Futaana, Y. et al. (2018) PSS, 156, 23-40 ; [7] Wurz et al. (2022) Space Sci. Rev., 218, 10 ; [8] Farrel, W.M. et al. (2023) Rev. In Min. & Geochem., 89, 563-609 ; [9] Denevi, B.W. et al. (2023) Rev. In Min. & Geochem., 89, 611-650 ; [10] Hurley, D.M. et al. (2023) Rev. In Min. & Geochem., 89, 787-827. [11] Moon to Mars Strategy and Objectives [12] AstroLEAP FDT report (ESA/FDT, 2024).