{"id":17600,"date":"2019-02-03T20:00:21","date_gmt":"2019-02-03T19:00:21","guid":{"rendered":"http:\/\/www.laterredufutur.com\/accueil\/?p=17600"},"modified":"2019-01-07T16:32:21","modified_gmt":"2019-01-07T15:32:21","slug":"un-tiers-des-exoplanetes-connues-seraient-des-planetes-oceans","status":"publish","type":"post","link":"https:\/\/www.laterredufutur.com\/accueil\/un-tiers-des-exoplanetes-connues-seraient-des-planetes-oceans\/","title":{"rendered":"Un tiers des exoplan\u00e8tes connues seraient des \u00ab\u00a0plan\u00e8tes-oc\u00e9ans\u00a0\u00bb"},"content":{"rendered":"<div class=\"1665f18d14f35dd9e7566e1a8ac9a3e9\" data-index=\"1\" style=\"float: none; margin:10px 0 10px 0; text-align:center;\">\n<script async src=\"https:\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js\"><\/script>\r\n<ins class=\"adsbygoogle\"\r\n     style=\"display:block; text-align:center;\"\r\n     data-ad-layout=\"in-article\"\r\n     data-ad-format=\"fluid\"\r\n     data-ad-client=\"ca-pub-2860849627502538\"\r\n     data-ad-slot=\"3019501113\"><\/ins>\r\n<script>\r\n     (adsbygoogle = window.adsbygoogle || []).push({});\r\n<\/script>\n<\/div>\n<p>Une \u00e9quipe de chercheurs de l\u2019Universit\u00e9 d\u2019Harvard a classifi\u00e9 les exoplan\u00e8tes selon leur rayon. Plus d\u2019un tiers d\u2019entre elles seraient recouvertes \u00e0 moiti\u00e9 d\u2019eau.<\/p>\n<p>Li Zeng, astronome \u00e0 Harvard et son \u00e9quipe ont publi\u00e9 en ao\u00fbt une \u00e9tude dans le Monthly Notices of the Royal Astronomical Society. Ils y proposent une nouvelle classification des 3 838 exoplan\u00e8tes d\u00e9couvertes \u00e0 ce jour, gr\u00e2ce notamment \u00e0 Kepler, en fonction de leur taille. Une classification qui permet de faire le lien entre la masse d\u2019une plan\u00e8te, son rayon, sa formation et sa composition.<\/p>\n<p>LE RAYON COMME PI\u00c8CE D\u2019IDENTIT\u00c9<br \/>\nLi Zeng et son \u00e9quipe se sont appuy\u00e9s sur les analyses du satellite GAIA de l\u2019Agence Spatiale Europ\u00e9enne pour appuyer un nouveau syst\u00e8me de classement, bas\u00e9 sur la constante RT (Rayon Terrestre). Ce qui fait \u00ab la beaut\u00e9 de ce mod\u00e8le \u00bb selon Li Zeng, c\u2019est qu\u2019il explique la relation entre la masse, le rayon et la composition des exoplan\u00e8tes. Selon ce syst\u00e8me, les plan\u00e8tes dont le rayon fait moins de 2 RT sont v\u00e9rifi\u00e9es comme \u00e9tant rocheuses et pauvres en eau. Entre 2 et 4 RT, on retrouve la cat\u00e9gorie des plan\u00e8tes-oc\u00e9ans, riches en eau. Entre 4 et 10 RT, les plan\u00e8tes sont riches en gaz et au-del\u00e0 de 10 RT, elles sont consid\u00e9r\u00e9es comme des g\u00e9antes gazeuses, majoritairement compos\u00e9e d\u2019hydrog\u00e8ne et d\u2019h\u00e9lium.<\/p>\n<p>Li Zeng conclut en affirmant que les dimensions des plan\u00e8tes contraignent leur formation et leur structure interne. Ce postulat lui a permis d&rsquo;expliquer la formation des plan\u00e8tes-oc\u00e9ans.<\/p><div class=\"1665f18d14f35dd9e7566e1a8ac9a3e9\" data-index=\"2\" style=\"float: none; margin:10px 0 10px 0; text-align:center;\">\n<script async src=\"https:\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js\"><\/script>\r\n<ins class=\"adsbygoogle\"\r\n     style=\"display:block; text-align:center;\"\r\n     data-ad-layout=\"in-article\"\r\n     data-ad-format=\"fluid\"\r\n     data-ad-client=\"ca-pub-2860849627502538\"\r\n     data-ad-slot=\"3019501113\"><\/ins>\r\n<script>\r\n     (adsbygoogle = window.adsbygoogle || []).push({});\r\n<\/script>\n<\/div>\n\n<p>DE NOMBREUSES SUPER-TERRES RECOUVERTES D\u2019EAU<br \/>\n\u00ab R\u00e9aliser que les plan\u00e8tes-oc\u00e9ans sont si nombreuses \u00e9tait une immense surprise \u00bb confie Li Zeng. En effet, plus d\u2019un tiers des exoplan\u00e8tes recens\u00e9es seraient recouvertes pour moiti\u00e9 d\u2019eau. \u00c0 titre de comparaison, les oc\u00e9ans de la Terre recouvrent 70,8 % de sa surface. Le chercheur apporte une r\u00e9ponse quant \u00e0 leur formation : \u00ab Les plan\u00e8tes-oc\u00e9ans se sont certainement form\u00e9es d\u2019une mani\u00e8re similaire aux g\u00e9antes gazeuses que l\u2019on trouve dans notre syst\u00e8me solaire. [\u2026] \u00c9chouant \u00e0 devenir des g\u00e9antes gazeuses \u00bb, elles auraient \u00e9volu\u00e9 diff\u00e9remment pour devenir des plan\u00e8tes riches en eau. Ces plan\u00e8tes se situent \u00e0 la limite sup\u00e9rieure d&rsquo;une cat\u00e9gorie d&rsquo;exoplan\u00e8tes appel\u00e9es super-terres, avec une masse environ 10 fois plus importante que celle de la Terre.<\/p>\n<p>Li Zeng avait r\u00e9cemment publi\u00e9 une seconde \u00e9tude, mettant \u00e9galement en relation le rayon des plan\u00e8tes et le type d\u2019\u00e9toile autour de laquelle elles orbitent. Le myst\u00e8re sur la formation demeure mais cette d\u00e9couverte est une belle avanc\u00e9e en mati\u00e8re de recherche de plan\u00e8tes similaires \u00e0 la n\u00f4tre et de vie extraterrestre.<\/p>\n<p>source : <a href=\"https:\/\/www.nationalgeographic.fr\/espace\/un-tiers-des-exoplanetes-connues-seraient-des-planetes-oceans?fbclid=IwAR2gYlLd0RjXq_mV4VPzr6Vdz4cSzP1itZGe58n9cxqfcWD-K2kV2ONPtBo\" target=\"_blank\" rel=\"noopener\">https:\/\/www.nationalgeographic.fr\/<\/a><\/p>\n<p class=\"bawpvc-ajax-counter\" data-id=\"17600\">(306)<\/p>\n<!--CusAds0-->\n<div style=\"font-size: 0px; height: 0px; line-height: 0px; margin: 0; padding: 0; clear: both;\"><\/div>","protected":false},"excerpt":{"rendered":"<p>Une \u00e9quipe de chercheurs de l\u2019Universit\u00e9 d\u2019Harvard a classifi\u00e9 les exoplan\u00e8tes selon leur rayon. Plus d\u2019un tiers d\u2019entre elles seraient&#8230;<\/p>\n","protected":false},"author":1,"featured_media":17601,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_exactmetrics_skip_tracking":false,"_exactmetrics_sitenote_active":false,"_exactmetrics_sitenote_note":"","_exactmetrics_sitenote_category":0,"ngg_post_thumbnail":0,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"Un tiers des exoplan\u00e8tes connues seraient des \"plan\u00e8tes-oc\u00e9ans\" @laterredufutur","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2},"jetpack_post_was_ever_published":false},"categories":[22],"tags":[333,359,6886,241,6887],"class_list":["post-17600","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-espace","tag-eau","tag-exoplanete","tag-li-zeng","tag-ocean","tag-planetes-oceans","wpcat-22-id"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2019\/01\/exoplan%C3%A8te-ocean.jpg?fit=1900%2C1069&ssl=1","jetpack_shortlink":"https:\/\/wp.me\/p631RN-4zS","jetpack-related-posts":[{"id":24340,"url":"https:\/\/www.laterredufutur.com\/accueil\/decouverte-dune-probable-planete-ocean\/","url_meta":{"origin":17600,"position":0},"title":"D\u00e9couverte d&rsquo;une probable plan\u00e8te oc\u00e9an","author":"Admin","date":"27 ao\u00fbt 2022","format":false,"excerpt":"Elle serait ainsi enti\u00e8rement recouverte d'une \u00e9paisse couche d'eau. Si on sait que l\u2019eau liquide est essentielle au d\u00e9veloppement de la vie, il est beaucoup trop t\u00f4t pour se prononcer sur la potentielle pr\u00e9sence de vie sur cette exoplan\u00e8te. TOI-1452 b est une exoplan\u00e8te en orbite autour d'une des deux\u2026","rel":"","context":"Dans &quot;Espace&quot;","block_context":{"text":"Espace","link":"https:\/\/www.laterredufutur.com\/accueil\/sujets\/espace\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2022\/08\/exoplanete-ocean.jpg?fit=1200%2C675&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2022\/08\/exoplanete-ocean.jpg?fit=1200%2C675&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2022\/08\/exoplanete-ocean.jpg?fit=1200%2C675&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2022\/08\/exoplanete-ocean.jpg?fit=1200%2C675&ssl=1&resize=700%2C400 2x, https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2022\/08\/exoplanete-ocean.jpg?fit=1200%2C675&ssl=1&resize=1050%2C600 3x"},"classes":[]},{"id":15166,"url":"https:\/\/www.laterredufutur.com\/accueil\/une-nouvelle-exoplanete-qui-pourrait-accueillir-la-vie\/","url_meta":{"origin":17600,"position":1},"title":"Une nouvelle exoplan\u00e8te qui pourrait accueillir la vie ?","author":"Admin","date":"9 mai 2017","format":false,"excerpt":"Elle porte le doux nom de LHS 1140b. Situ\u00e9e dans la zone habitable autour d'une \u00e9toile situ\u00e9e \u00e0 40 ann\u00e9es lumi\u00e8res de notre syst\u00e8me solaire, ce monde rocheux a toutes les caract\u00e9ristiques pour qu'on y d\u00e9couvre \u00e9ventuellement la pr\u00e9sence d'eau \u00e0 sa surface. LHS 1140b grimpe en t\u00eate de la\u2026","rel":"","context":"Dans &quot;Espace&quot;","block_context":{"text":"Espace","link":"https:\/\/www.laterredufutur.com\/accueil\/sujets\/espace\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2017\/02\/exoplanete.jpg?fit=1024%2C415&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2017\/02\/exoplanete.jpg?fit=1024%2C415&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2017\/02\/exoplanete.jpg?fit=1024%2C415&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2017\/02\/exoplanete.jpg?fit=1024%2C415&ssl=1&resize=700%2C400 2x"},"classes":[]},{"id":25919,"url":"https:\/\/www.laterredufutur.com\/accueil\/un-monde-potentiellement-habitable-de-la-taille-de-la-terre-decouvert-a-40-annees-lumiere\/","url_meta":{"origin":17600,"position":2},"title":"Un monde potentiellement habitable de la taille de la Terre d\u00e9couvert \u00e0 40 ann\u00e9es-lumi\u00e8re","author":"Admin","date":"27 mai 2024","format":false,"excerpt":"Une plan\u00e8te qui ressemble \u00e0 s'y m\u00e9prendre \u00e0 la Terre vient d'\u00eatre d\u00e9couverte en orbite autour d'une \u00e9toile situ\u00e9e \u00e0 seulement 40 ann\u00e9es-lumi\u00e8re du syst\u00e8me solaire. Cette exoplan\u00e8te a un rayon tr\u00e8s similaire \u00e0 celui de notre plan\u00e8te, ce qui laisse supposer une composition rocheuse similaire. Il est int\u00e9ressant de\u2026","rel":"","context":"Dans &quot;Espace&quot;","block_context":{"text":"Espace","link":"https:\/\/www.laterredufutur.com\/accueil\/sujets\/espace\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2024\/05\/Gliese-12-exoplanete.jpg?fit=642%2C361&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2024\/05\/Gliese-12-exoplanete.jpg?fit=642%2C361&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2024\/05\/Gliese-12-exoplanete.jpg?fit=642%2C361&ssl=1&resize=525%2C300 1.5x"},"classes":[]},{"id":22352,"url":"https:\/\/www.laterredufutur.com\/accueil\/il-pleut-dans-tout-le-systeme-solaire-a-quoi-ressemble-cette-pluie\/","url_meta":{"origin":17600,"position":3},"title":"Il pleut dans tout le syst\u00e8me solaire, \u00e0 quoi ressemble cette pluie ?","author":"Admin","date":"10 avril 2021","format":false,"excerpt":"\u00c0 quoi ressembleraient les gouttes de pluie sur d'autres mondes? Les pr\u00e9cipitations sont beaucoup plus r\u00e9pandues dans tout le syst\u00e8me solaire qu'on ne le pense g\u00e9n\u00e9ralement. De toute \u00e9vidence, il pleut de l'eau sur Terre, mais il neige du dioxyde de carbone sur Mars, il pleut du m\u00e9thane sur Titan,\u2026","rel":"","context":"Dans &quot;Espace&quot;","block_context":{"text":"Espace","link":"https:\/\/www.laterredufutur.com\/accueil\/sujets\/espace\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2021\/04\/pluie-titan.jpg?fit=1050%2C700&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2021\/04\/pluie-titan.jpg?fit=1050%2C700&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2021\/04\/pluie-titan.jpg?fit=1050%2C700&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2021\/04\/pluie-titan.jpg?fit=1050%2C700&ssl=1&resize=700%2C400 2x, https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2021\/04\/pluie-titan.jpg?fit=1050%2C700&ssl=1&resize=1050%2C600 3x"},"classes":[]},{"id":25249,"url":"https:\/\/www.laterredufutur.com\/accueil\/le-telescope-james-webb-decouvre-du-methane-et-du-dioxyde-de-carbone-dans-latmosphere-de-k2-18-b\/","url_meta":{"origin":17600,"position":4},"title":"Le t\u00e9lescope James Webb d\u00e9couvre du m\u00e9thane et du dioxyde de carbone dans l&rsquo;atmosph\u00e8re de K2-18 b","author":"Admin","date":"27 septembre 2023","format":false,"excerpt":"Une nouvelle observation de K2-18 b, une exoplan\u00e8te 8,6 fois plus massive que la Terre, par le t\u00e9lescope spatial James Webb de la NASA a r\u00e9v\u00e9l\u00e9 la pr\u00e9sence de mol\u00e9cules contenant du carbone, notamment du m\u00e9thane et du dioxyde de carbone. La d\u00e9couverte de M. Webb vient s'ajouter \u00e0 de\u2026","rel":"","context":"Dans &quot;Espace&quot;","block_context":{"text":"Espace","link":"https:\/\/www.laterredufutur.com\/accueil\/sujets\/espace\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2023\/09\/exoplanete-K2-18b.jpg?fit=985%2C554&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2023\/09\/exoplanete-K2-18b.jpg?fit=985%2C554&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2023\/09\/exoplanete-K2-18b.jpg?fit=985%2C554&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2023\/09\/exoplanete-K2-18b.jpg?fit=985%2C554&ssl=1&resize=700%2C400 2x"},"classes":[]},{"id":14996,"url":"https:\/\/www.laterredufutur.com\/accueil\/des-scientifiques-viennent-de-detecter-une-atmosphere-sur-une-exoplanete\/","url_meta":{"origin":17600,"position":5},"title":"Des scientifiques viennent de d\u00e9tecter une atmosph\u00e8re sur une exoplan\u00e8te","author":"Admin","date":"15 avril 2017","format":false,"excerpt":"La recherche de formes de vie extraterrestre est sans doute l\u2019une des qu\u00eates les plus exaltantes de l\u2019univers. Des chercheurs viennent de d\u00e9couvrir une atmosph\u00e8re autour de Gliese 1132b, une exoplan\u00e8te de la taille de la Terre, faisant d\u2019elle une candidate potentielle au d\u00e9veloppement de la vie. LA D\u00c9COUVERTE D\u2019UNE\u2026","rel":"","context":"Dans &quot;Espace&quot;","block_context":{"text":"Espace","link":"https:\/\/www.laterredufutur.com\/accueil\/sujets\/espace\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2017\/04\/GJ-1132b.jpg?fit=904%2C508&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2017\/04\/GJ-1132b.jpg?fit=904%2C508&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2017\/04\/GJ-1132b.jpg?fit=904%2C508&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2017\/04\/GJ-1132b.jpg?fit=904%2C508&ssl=1&resize=700%2C400 2x"},"classes":[]}],"jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.laterredufutur.com\/accueil\/wp-json\/wp\/v2\/posts\/17600","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.laterredufutur.com\/accueil\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.laterredufutur.com\/accueil\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.laterredufutur.com\/accueil\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.laterredufutur.com\/accueil\/wp-json\/wp\/v2\/comments?post=17600"}],"version-history":[{"count":1,"href":"https:\/\/www.laterredufutur.com\/accueil\/wp-json\/wp\/v2\/posts\/17600\/revisions"}],"predecessor-version":[{"id":17602,"href":"https:\/\/www.laterredufutur.com\/accueil\/wp-json\/wp\/v2\/posts\/17600\/revisions\/17602"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.laterredufutur.com\/accueil\/wp-json\/wp\/v2\/media\/17601"}],"wp:attachment":[{"href":"https:\/\/www.laterredufutur.com\/accueil\/wp-json\/wp\/v2\/media?parent=17600"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.laterredufutur.com\/accueil\/wp-json\/wp\/v2\/categories?post=17600"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.laterredufutur.com\/accueil\/wp-json\/wp\/v2\/tags?post=17600"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}