16:30 〜 16:45
[PPS05-05] Millimeter- to kilometer-scale topographic roughness of airless bodies: implications for the small-scale topographic irregularities on Phobos
キーワード：フォボス、火星衛星探査計画、起伏
The topographic roughness of the solar system bodies is a surface remnant that is the result of the evolutionary history of the bodies. The quantitative measurements of topographic roughness and its scale dependence could be powerful tools for interpreting its origin (e.g., Kreslavsky et al., 2013; Cai & Fa, 2020). The characterized roughness features of each body have been compared in the previous studies, where differences in the impact history and regolith properties have been proposed (e.g., Ermakov et al., 2019). More studies on the scale dependence of the topographic roughness of each body should further clarify the differences in their geological features.
In addition, the study of the scale dependency of the topographic roughness of each solar system body is essential to ensure the engineering safety of landing explorations. Topographic roughness prevents the safe landing and roving on the target body and should be carefully studied prior to the mission launch. However, the topographic roughness is usually unknown for most bodies due to the lack of high-resolution images. Studying the scale dependence of topographic roughness can provide us with a unique key perspective to estimate the small-scale topographic roughness of bodies for which only larger-scale topography is known. Therefore, in this research, we characterize the scale dependence of the topographic roughness of solar system bodies and discuss the estimation of the small-scale topographic irregularities. Our specific target is Phobos, which will be explored by the JAXA’s MMX missions scheduled to launch in 2024.
In this research, we first characterize the millimeter to kilometer scale topographic irregularities of several airless bodies and evaluate the scale dependency of the topographic features. The global and regional Digital Terrain Model (DTM) with millimeter to kilometer resolution is evaluated by several indices such as Power Spectral Density (PSD), RMS height, and bidirectional slope. We also analyze the topographic irregularities on Phobos by the global DTM and the high-resolution regional DTM on the specific area near the Stickney crater (Takemura et al., 2021). The results of the PSD show that the topographic features of the Phobos’ regional DTM have the same trend for the lunar surface in the meter to 100-meter scales. In the presentation, we will discuss the detailed results of the analyzed scale dependence of topographic irregularities on airless bodies and the implications for the small-scale topographic irregularities on Phobos.
References:
Kreslavsky et al., Icarus, 226(1), 52-66 (2013).
Cai & Fa, Journal of Geophysical Research: Planets, 125(8), e2020JE006429 (2020).
Ermakov et al., Journal of Geophysical Research: Planets, 124(1), 14-30 (2019).
Takemura et al., Earth, Planets and Space, 73(1), 1-14 (2021).
In addition, the study of the scale dependency of the topographic roughness of each solar system body is essential to ensure the engineering safety of landing explorations. Topographic roughness prevents the safe landing and roving on the target body and should be carefully studied prior to the mission launch. However, the topographic roughness is usually unknown for most bodies due to the lack of high-resolution images. Studying the scale dependence of topographic roughness can provide us with a unique key perspective to estimate the small-scale topographic roughness of bodies for which only larger-scale topography is known. Therefore, in this research, we characterize the scale dependence of the topographic roughness of solar system bodies and discuss the estimation of the small-scale topographic irregularities. Our specific target is Phobos, which will be explored by the JAXA’s MMX missions scheduled to launch in 2024.
In this research, we first characterize the millimeter to kilometer scale topographic irregularities of several airless bodies and evaluate the scale dependency of the topographic features. The global and regional Digital Terrain Model (DTM) with millimeter to kilometer resolution is evaluated by several indices such as Power Spectral Density (PSD), RMS height, and bidirectional slope. We also analyze the topographic irregularities on Phobos by the global DTM and the high-resolution regional DTM on the specific area near the Stickney crater (Takemura et al., 2021). The results of the PSD show that the topographic features of the Phobos’ regional DTM have the same trend for the lunar surface in the meter to 100-meter scales. In the presentation, we will discuss the detailed results of the analyzed scale dependence of topographic irregularities on airless bodies and the implications for the small-scale topographic irregularities on Phobos.
References:
Kreslavsky et al., Icarus, 226(1), 52-66 (2013).
Cai & Fa, Journal of Geophysical Research: Planets, 125(8), e2020JE006429 (2020).
Ermakov et al., Journal of Geophysical Research: Planets, 124(1), 14-30 (2019).
Takemura et al., Earth, Planets and Space, 73(1), 1-14 (2021).