LINK<\/strong><\/a><\/p>\n“Highlights<\/p>\n
\u2022 We irradiate carbonaceous meteorites with 40\u202fkeV ions simulating asteroid weathering.
\n\u2022 We perform FTIR micro-spectral imaging on areas irradiated with different doses.
\n\u2022 Irradiated anhydrous and hydrated silicates peak positions show spectral redshifts.
\n\u2022 We separate compositional heterogeneity of pristine materials and irradiation effects.
\n\u2022 We discuss implications for Hayabusa-2 and OSIRIS-REx sample return missions.”<\/p>\n
“Space weathering produces variations in the optical properties of small solar system body surfaces. Laboratory studies have been performed by several groups on different meteorite classes, aimed at simulating space weathering by using ion irradiation and laser ablation. Here we present new FTIR spectral imaging data of ion irradiated carbonaceous chondrites (CV Allende and CM Murchison meteorites), simulating solar wind irradiation on primitive asteroids. Irradiation conditions (40\u202fkeV He+ and Ar+ up to 3.1016 ion\/cm2) were reported in detail in previous studies. The new analyses were performed with a FTIR micro-spectrometer equipped with an FPA (Focal Plane Array) detector. Micro-reflectance spectra were acquired in the 2.5\u201312\u202f\u03bcm range using a spot size of 20\u202f\u03bcm and scanning large areas (from mm2 to cm2) of the meteorite pellets, both on virgin areas and on areas irradiated with different doses. Spectral maps allow us characterizing the heterogeneity of the meteorites at the 20\u202f\u03bcm spatial scale. In the irradiated areas, we observe spectral modifications of both anhydrous and hydrated silicates. Spectral shifts are observed after irradiation, larger for anhydrous than hydrated silicates. Compositional heterogeneity of the pristine materials and irradiation effects are compared to each other as a function of the irradiation dose, to determine which spectral features are more sensitive to space weathering. Results are then compared with the IR spectral capabilities of instruments onboard the Hayabusa2\/JAXA and OSIRIS-REx\/NASA spacecrafts, to provide these missions with spectral criteria on how to distinguish space weathering from compositional heterogeneity effects at the asteroid, and in view of surface selection for sample return.”<\/p>\n","protected":false},"excerpt":{"rendered":"
R. Brunetto, C. Lantz, Z. Dionnet, F. Borondics, A. Al\u00e9on-Toppani, D. Baklouti, M.A. Barucci, R.P. Binzel, Z. Djouadi, K. Kitazato, C. Pilorget Planetary and Space Science Available online 8 May 2018 LINK “Highlights \u2022 We…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[77,9,18,14,2243,552,130,181,1184],"tags":[108,1771,3273,105,1812,2551,509,107,2173,673],"_links":{"self":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/14790"}],"collection":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=14790"}],"version-history":[{"count":1,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/14790\/revisions"}],"predecessor-version":[{"id":14791,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/14790\/revisions\/14791"}],"wp:attachment":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=14790"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=14790"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=14790"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}