09:30 〜 09:45
[PCG20-03] A LIBS station concept for lunar missions
Introduction: Lunar polar volatiles including water preserve ancient materials from external delivery and internal degassing. Missions to the lunar south pole aim to locate volatiles and quantify their abundances. They also determine volatile sources and examine trapping, loss mechanisms, and interactions with both surface and subsurface regolith. For example, NASA Artemis and JAXA LUPEX will address these objectives [1]. Characterization of water reservoirs requires identification of correlations with rock types, minerals, or physical conditions. In-situ measurements with high spatial and temporal resolution offer a valuable addition to returning stratigraphically intact samples that contain ice. Moreover, the lunar south pole is an interesting region as it lies several hundred kilometers from moderately high potassium areas and gabbronoritic lithologies in the South Pole Aitken (SPA) basin [2]. Ejecta from these regions likely reached the south pole. Large craters such as Shackleton and Shoemaker create further complex local stratigraphy and geology. Analysis of fragment concentrations and identification of geologic endmembers will enhance understanding of impact-driven mixing processes and lunar crustal evolution around the SPA basin.
LIBS Capabilities: Laser-induced breakdown spectroscopy (LIBS) quantifies hydrogen and rock-forming elements. Yumoto et al. [3] reported that a partial least squares calibration model yields a relative error of approximately 20%. With univariate calibration, detection limits fall below 0.1 weight percent water and median relative errors near 10 percent. Experiments under vacuum (less than 4e-2 Pa) demonstrated standoff LIBS spectra acquisition at distances of 1 to 5 m [4]. LIBS also measures major elements in regolith and rocks at the same scale as hydrogen. Under lunar-like vacuum conditions, Yumoto et al. [5] achieved accuracies below 10 percent for silicon, magnesium, calcium, aluminum, and sodium and below 15 percent for iron, potassium, and titanium. This performance differentiates key lithologies at the lunar south pole, including upper crust anorthosites, lower crust noritic anorthosites, and basalts. Detection of potassium at 100 parts per million on a millimeter scale [6] supports identification of gabbronoritic KREEPy upper mantle material from the South Pole Aitken basin [2]. Potassium abundance measurements further contribute to in-situ geochronology via potassium-argon dating [7, 8].
LIBS Station Concept: To conduct these analyses on the Moon, a dedicated LIBS station was developed. It integrates a laser, spectrometer, context imager, optics, and field programmable gate array-based electronics into a self-contained unit. Its size fits 50 x 50 x 50 cm envelope and weighs < 25 kg total. A gimbal mounted mirror permits autonomous scanning in elevation and azimuth, while an autofocus lens assembly allows for analyses up to ~10 m. Solar panels generate power and enable direct communication with Earth using an X-band antenna. The station scans areas exceeding 100 square meters near the landing site. It examines regolith, large boulders that cannot be returned to Earth (> 50 cm), and shadowed regions. The instrument attains submillimeter vertical resolution and approximately 1 millimeter horizontal resolution while detecting hydrogen and eight major elements over an entire lunar day. These capabilities address science objectives relevant to lunar polar exploration.
References: [1] Artemis III Science Definition Team Report (2021) [2] Moriarty D. P. et al. (2021) JGR 121, e2020JE006589. [3] Yumoto K. et al. (2023) Spectrochim. Acta B. 205, 106696. [4] Cho Y. et al. (2025) LPSC 56, 1752. [5] Yumoto K. et al. (2024) Spectrochim. Acta B.221, 107049. [6] Cho Y. et al. (2017) Appl. Spectrosc, 71,1969. [7] Cho Y. & Cohen B. A. (2018) Rapid Comm Mass Spectrom. 32, 1755–1765. [8] Cattani, F. et al. (2023) MaPS 58, 591.
LIBS Capabilities: Laser-induced breakdown spectroscopy (LIBS) quantifies hydrogen and rock-forming elements. Yumoto et al. [3] reported that a partial least squares calibration model yields a relative error of approximately 20%. With univariate calibration, detection limits fall below 0.1 weight percent water and median relative errors near 10 percent. Experiments under vacuum (less than 4e-2 Pa) demonstrated standoff LIBS spectra acquisition at distances of 1 to 5 m [4]. LIBS also measures major elements in regolith and rocks at the same scale as hydrogen. Under lunar-like vacuum conditions, Yumoto et al. [5] achieved accuracies below 10 percent for silicon, magnesium, calcium, aluminum, and sodium and below 15 percent for iron, potassium, and titanium. This performance differentiates key lithologies at the lunar south pole, including upper crust anorthosites, lower crust noritic anorthosites, and basalts. Detection of potassium at 100 parts per million on a millimeter scale [6] supports identification of gabbronoritic KREEPy upper mantle material from the South Pole Aitken basin [2]. Potassium abundance measurements further contribute to in-situ geochronology via potassium-argon dating [7, 8].
LIBS Station Concept: To conduct these analyses on the Moon, a dedicated LIBS station was developed. It integrates a laser, spectrometer, context imager, optics, and field programmable gate array-based electronics into a self-contained unit. Its size fits 50 x 50 x 50 cm envelope and weighs < 25 kg total. A gimbal mounted mirror permits autonomous scanning in elevation and azimuth, while an autofocus lens assembly allows for analyses up to ~10 m. Solar panels generate power and enable direct communication with Earth using an X-band antenna. The station scans areas exceeding 100 square meters near the landing site. It examines regolith, large boulders that cannot be returned to Earth (> 50 cm), and shadowed regions. The instrument attains submillimeter vertical resolution and approximately 1 millimeter horizontal resolution while detecting hydrogen and eight major elements over an entire lunar day. These capabilities address science objectives relevant to lunar polar exploration.
References: [1] Artemis III Science Definition Team Report (2021) [2] Moriarty D. P. et al. (2021) JGR 121, e2020JE006589. [3] Yumoto K. et al. (2023) Spectrochim. Acta B. 205, 106696. [4] Cho Y. et al. (2025) LPSC 56, 1752. [5] Yumoto K. et al. (2024) Spectrochim. Acta B.221, 107049. [6] Cho Y. et al. (2017) Appl. Spectrosc, 71,1969. [7] Cho Y. & Cohen B. A. (2018) Rapid Comm Mass Spectrom. 32, 1755–1765. [8] Cattani, F. et al. (2023) MaPS 58, 591.