LINK<\/strong><\/a><\/p>\n\n\n\n“Highlights<\/p>\n\n\n\n
\u2022 146 HEDs have similar \u039417O values of \u22120.240\u202f\u00b1\u202f0.020\u2030 (2\u03c3) and derive from 4Vesta.
\n\u2022 Oxygen isotopes anomalies of 5 HEDs are caused by external factors.
\n\u2022 15 oxygen-anomalous HEDs are likely to originate from at least five different asteroids.
\n\u2022 The conclusions are supported by astrophysical and other geochemical studies.”<\/p>\n\n\n\n
“The howardite, eucrite and diogenite (HED) clan of meteorites are usually regarded as Vesta meteorites, but there is still serious controversy over whether Vesta is the only parent body for HEDs. Different numbers of HED parent asteroids have been proposed in previous studies of oxygen isotopes. The main controversy is whether the anomalous oxygen isotopic compositions in some HEDs are caused by factors such as terrestrial weathering, addition of exogenous material during brecciation, or a possible primary isotopic heterogeneity of Vesta. To readdress the questions of whether all HED meteorites are from the same parent body, or to constrain the possible number of multiple parent asteroids, the oxygen isotopic data of 166 HED meteorites from the literature are compiled and reviewed here. Among them, 146 HED meteorites have similar \u039417O values of \u22120.240\u202f\u00b1\u202f0.020\u2030 (2\u03c3), and the remaining 20 meteorites show oxygen isotopic anomalies (\u039417O values fall outside 3\u03c3 from the above mean). Fifteen HED meteorites have anomalous oxygen isotope compositions that cannot be accounted for by terrestrial weathering or the addition of exogenous material, while the oxygen isotope anomalies in the remaining 5 HEDs are caused by the above factors. Based on studies of a number of isotopic and trace element systems, HED meteorites should form from a magma ocean, thus their parent asteroid is highly likely to be homogeneous. This implies that the oxygen isotope variability of HEDs suggest multiple parent bodies for these meteorites, which is supported by arguments from astrophysical and other geochemical studies such as Zn and Cr. In summary, according to the \u039417O values and a number of other observations, we believe that HED meteorites most likely originate from at least 6 different basaltic asteroids.”<\/p>\n","protected":false},"excerpt":{"rendered":"
Chuantong Zhang, Bingkui Miao, Huaiyu He Planetary and Space Science In Press, Accepted Manuscript, Available online 19 February 2019 LINK “Highlights \u2022 146 HEDs have similar \u039417O values of \u22120.240\u202f\u00b1\u202f0.020\u2030 (2\u03c3) and derive from 4Vesta….<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[36,35,33,34,65,137],"tags":[4517,1824,1823,212,2108,1822,1872],"_links":{"self":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/17688"}],"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=17688"}],"version-history":[{"count":1,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/17688\/revisions"}],"predecessor-version":[{"id":17689,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/17688\/revisions\/17689"}],"wp:attachment":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=17688"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=17688"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=17688"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}