Coordinated Analysis of an Ion Irradiated Carbonaceous Chondrite Suggests Complex Space Weathering Effects

Laczniak, D L ; Thompson, M S ; Christoffersen, Roy G

关键词: GEOCHEMISTRY;    ION IRRADIATION;    CARBONACEOUS CHONDRITES;    MURCHISON METEORITE;    SPACE WEATHERING;    MINERALOGY;    ASTEROIDS;    IMAGING SPECTROMETERS;    SPECTRAL REFLECTANCE;    OSIRIS-REX;    BENNU ASTEROID;    REMOTE SENSING;    JAPANESE SPACE PROGRAM;    NASA SPACE PROGRAMS;   

RP-ID  :  LPI Contrib. No. 2132,JSC-E-DAA-TN66087

学科分类：天文学(综合)

美国|英语

来源: NASA Technical Reports Server

【 摘 要 】

Surfaces of airless planetary bodies are exposed to micrometeorite bombardment and solar wind irradiation which alter the microstructural, compositional, and optical properties of regoliths over time. These processes are collectively known as space weathering, and they complicate the interpretation of remote sensing data and the subsequent characterization of airless surfaces. Within the next 5 years, NASA’s OSIRIS-REx(Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer) and JAXA (Japan Aerospace Exploration Agency)’s Hayabusa2 missions will return samples from C-type asteroids Bennu and Ryugu, respectively. Compared to the Moon and S-type asteroids, our understanding of the space weathering of C-complex asteroids is limited. In order to maximize scientific return from remote sensing data and to prepare for the analysis of returned samples from these missions, we must better understand the effects of space weathering on hydrated, organic-rich materials. We can do so by simulating these processes in the laboratory. In this study, we simulate solar wind exposure through ion irradiation of the CM2 carbonaceous chondrite Murchison - a suitable analog for C-complex asteroids. Here, we present coordinated analyses of a sample before and after ion irradiation.