LINK<\/strong><\/a><\/p>\n\n\n\n“Highlights<\/p>\n\n\n\n
\u2022 Ceres\u2019 shape agrees with an organic-rich interior suggested from the surface composition.
\n\u2022 Ceres could consist of a mixture of 12\u201329 vol.% C-H-O-N-S organic matter and aqueously altered rocks with the composition of CI chondrites.
\n\u2022 Water ice is not required to explain density of the body and its upper interior layer.
\n\u2022 Interior density distribution is explained by compaction of a chemically uniform material.
\n\u2022 Ceres could have accreted between formation regions of CI chondrites and outer solar system bodies.”<\/p>\n\n\n\n
“Results of Ceres’ exploration with the Dawn spacecraft are modeled and discussed in terms of rock\/organic\/elemental composition, density and porosity in the interior, and formation, migration and geological evolution of the body. Carbon-rich surface composition is used to assess phase and elemental composition of the interior. The consistent bulk density and surface composition suggest an abundant organic matter within the body. Ceres is modeled as a chemically uniform mixture of CI-type carbonaceous chondritic rocks and 12\u201329\u202fvol% of macromolecular organic matter. Water ice, gas hydrates or high porosity (>10%) are not required to explain bulk density. Ceres may not have a partially differentiated interior structure because gravity and shape could be explained by compaction of chemically uniform materials. Gravity data suggest a two-layer structure with an abrupt density change. Gravity may not reflect the current global density distribution in the interior because the implied bulk porosity >9% and grain density\u202f>\u202f2380\u202fkg\u202fm\u22123 disagree with organic-rich compositions. In contrast, Ceres’ polar flattening indicates mild density gradients that could be explained by two-layer and gradual compaction models. The flattening implies grain density of 2200\u20132350\u202fkg\u202fm\u22123 that is consistent with the organic-rich interior. Viscosity of warmed rock-organic mixtures at depth could account for the observed relaxation of long wavelength topography. The organic-rich composition together with abundant surface carbonates, NH4-bearing phases suggests Ceres’ formation at larger heliocentric distances and later than CI chondrites. Ceres-forming materials could have been more water-rich than parent bodies of CI chondrites and excessive water could have been lost from the body. A majority of Ceres’ surface compounds could have formed through water-rock-organic reactions in a middle interior followed by collisional stripping of an upper interior.”<\/p>\n","protected":false},"excerpt":{"rendered":"
Mikhail Yu. Zolotov Icarus Available online 7 August 2019, 113404 LINK “Highlights \u2022 Ceres\u2019 shape agrees with an organic-rich interior suggested from the surface composition. \u2022 Ceres could consist of a mixture of 12\u201329 vol.%…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[74,9,167,10,360,1700],"tags":[3273,1868,1809,1880,1989],"_links":{"self":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/20224"}],"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=20224"}],"version-history":[{"count":2,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/20224\/revisions"}],"predecessor-version":[{"id":20226,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/20224\/revisions\/20226"}],"wp:attachment":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=20224"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=20224"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=20224"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}