{"id":27399,"date":"2021-04-21T07:42:07","date_gmt":"2021-04-21T05:42:07","guid":{"rendered":"https:\/\/karmaka.de\/?p=27399"},"modified":"2021-05-06T06:49:30","modified_gmt":"2021-05-06T04:49:30","slug":"origins-of-colors-variability-among-c-cluster-main-belt-asteroids","status":"publish","type":"post","link":"https:\/\/karmaka.de\/?p=27399","title":{"rendered":"Origins of colors variability among C-cluster main-belt asteroids<span class=\"badge-status\" style=\"background:#787878\">OPEN ACCESS<\/span>&nbsp;"},"content":{"rendered":"\n<p>Pierre Beck, Olivier Poch<\/p>\n\n\n\n<p>Icarus<br>Available online: 21 April 2021<\/p>\n\n\n\n<p><a href=\"https:\/\/www.sciencedirect.com\/science\/article\/abs\/pii\/S0019103521001731\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>LINK<\/strong><\/a><\/p>\n\n\n\n<p>Update (6 May 2021): <a rel=\"noreferrer noopener\" href=\"https:\/\/arxiv.org\/ftp\/arxiv\/papers\/2105\/2105.01912.pdf\" target=\"_blank\"><strong>PDF (OPEN ACCESS)<\/strong><\/a><\/p>\n\n\n\n<p>&#8220;Highlights<\/p>\n\n\n\n<p>\u2022 A C-type cluster is identified by an SDSS colors &amp; albedo cluster analysis.<br>\u2022 The C-cluster matches CM chondrites but generally not other type of CC.<br>\u2022 Small C-type MBAs appear bluer (&lt;20\u202fkm) than large ones (D\u202f&gt;\u202f20\u202fkm).<br>\u2022 We suggest that bluer objects are covered by larger grained material (&gt;mm to rocks).&#8221;<\/p>\n\n\n\n<p class=\"justify-text\">&#8220;The Sloan Digital Sky Survey provides colors for more than 100,000 moving objects, among which around 10,000 have albedos determined. Here we combined colors and albedo in order to perform a cluster analysis on the small bodies population, and identify a C-cluster, a group of asteroid related to C-type as defined in earlier work. Members of this C-cluster are in fair agreement with the color boundaries of B and C-type defined in DeMeo and Carry (2013). We then compare colors of C-cluster asteroids to those of carbonaceous chondrites powders, while taking into account the effect of phase angle. We show that only CM chondrites have colors in the range of C-cluster asteroids, CO, CR and CV chondrites being significantly redder. Also, CM chondrites powders are on average slightly redder than the average C-cluster. The colors of C-cluster members are further investigated by looking at color variations as a function of asteroid diameter. We observe that the visible slope becomes bluer with decreasing asteroids diameter, and a transition seems to be present around 20\u202fkm. We discuss the origin of this variation and, if not related to a bias in the dataset &#8211; analysis, we conclude that it is related to the surface texture of the objects, smaller objects being covered by rocks, while larger objects are covered by a particulate surface. The blueing is interpreted by an increased contribution of the first reflection in the case of rock-dominated surfaces, which can scatter light in a Rayleigh-like manner. We do not have unambiguous evidence of space weathering within the C-cluster based on this analysis, however the generally bluer nature of C-cluster objects compared to CM chondrites could be to some extent related to space weathering.&#8221;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Pierre Beck, Olivier Poch IcarusAvailable online: 21 April 2021 LINK Update (6 May 2021): PDF (OPEN ACCESS) &#8220;Highlights \u2022 A C-type cluster is identified by an SDSS colors &amp; albedo cluster analysis.\u2022 The C-cluster matches&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[77,5445,2350,9,18,127,130,3504,1184],"tags":[1768,1854,5928,3274,3273,105,1479,673],"_links":{"self":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/27399"}],"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=27399"}],"version-history":[{"count":2,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/27399\/revisions"}],"predecessor-version":[{"id":27672,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/27399\/revisions\/27672"}],"wp:attachment":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=27399"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=27399"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=27399"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}