^1,2PengYue Wang,³Edward Cloutis,¹XiaoPing Zhang,^1,4Ye Su,^1,5YunZhao Wu
Meteoritics & Planetary Science(in Press) Link to Article [https://doi.org/10.1111/maps.14077]
¹State Key Laboratory of Lunar and Planetary Sciences, Macau University of Science and Technology, Macau, China
²Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing, China
³Department of Geography, University of Winnipeg, Winnipeg, Canada
⁴Center for Excellence in Comparative Planetology, Chinese Academy of Science, Hefei, China
⁵Key Laboratory of Planetary Sciences, Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing, Chi
Published by arrangement with John Wiley & Sons

The impact threat of some near-Earth Asteroids (NEAs) drives our need to understand their mineral compositions. Quantitative mineral abundances based on reflectance spectroscopy are of great significance for studying the compositions of NEAs. In this study, we constrained the surface mineralogy of (99942) Apophis based on multiple diagnostic spectral parameters. The influence of non-mineral component factors (e.g., space weathering, phase angle, and surface temperature) on diagnostic spectral parameters was evaluated. We established the connection between Apophis and corresponding meteorite analog. Our results show that the abundances of olivine and pyroxene on the surface of Apophis are 53.4 ± 6 wt% and 35.6 ± 2 wt%, respectively. The 1 μm band width is basically unaffected by phase-angle changes and is less affected by temperature variations. Low temperature has more obvious effects on the 1.25/1 μm band depth ratio (BDR 1.25) based on the present data. When the phase angle ranges from 60° to 120°, the BDR 1.25 changes significantly with the increase or decrease of phase angle. In terms of spectral characteristics, the best meteorite analog of Apophis is LL chondrite, confirming earlier interpretations. Mineral analyses based on multiple diagnostic spectral parameters provide more consistent results. Knowledge of the surface compositions of Apophis can also inform optimum or possible defense strategies for it and other NEAs.

¹Juraj Tóth et al. (>10)
Icarus (in Press) Link to Article [https://doi.org/10.1016/j.icarus.2023.115791]
¹Faculty of Mathematics, Physics and Informatics, Comenius University Bratislava, Mlynska dolina, Bratislava, 84248, Slovakia
Copyright : Elsevier

We provide an overview of the MetSpec project, which aims to connect meteorite ablation laboratory experiments with meteor spectral observations in the atmosphere aiming at the development of a methodology to identify incoming planetary material distribution into the Earth’s atmosphere. We have selected 28 meteorites of different types to represent known planetary material compositions coming from asteroids, Vesta, Mars and the Moon. Some samples have been tested twice which resulted in overall 31 experiments. Three distinct test campaigns were realized in 2020, 2021 and 2022 with the High Enthalpy Flow Diagnostics Group in the Plasma Wind Tunnel PWK1 where they have developed a unique testing scenario. During the last and most elaborated campaign, 16 cameras observed the artificial meteors in the laboratory. Besides videos and online live streaming, instruments included several spectrometers, and optical and imaging instruments covering UV, visible and IR spectral range. This special collection in Icarus collects the resulting output from the different instruments and results. This overview article provides an introduction and summarizes the main findings of the experimental campaigns.