{"id":607313,"date":"2025-12-18T11:35:27","date_gmt":"2025-12-18T11:35:27","guid":{"rendered":"https:\/\/www.europesays.com\/fr\/607313\/"},"modified":"2025-12-18T11:35:27","modified_gmt":"2025-12-18T11:35:27","slug":"la-terre-se-serait-formee-dans-un-bain-de-rayons-cosmiques","status":"publish","type":"post","link":"https:\/\/www.europesays.com\/fr\/607313\/","title":{"rendered":"La Terre se serait form\u00e9e dans un bain de rayons cosmiques"},"content":{"rendered":"<p>\n    <strong>D\u00c9CRYPTAGE &#8211;<\/strong> Une explosion d\u2019\u00e9toile survenue \u00e0 proximit\u00e9 du Syst\u00e8me solaire dans ses premiers millions d\u2019ann\u00e9es d\u2019existence expliquerait sa teneur \u00e9lev\u00e9e en aluminium radioactif, un param\u00e8tre cl\u00e9 dans la formation des plan\u00e8tes rocheuses.<\/p>\n<p class=\"fig-paragraph\">Lorsque notre Syst\u00e8me solaire s\u2019est form\u00e9, il \u00e9tait particuli\u00e8rement riche en \u00e9l\u00e9ments radioactifs \u00e0 \u00abcourte\u00bb dur\u00e9e de vie, ou SLR (en anglais\u00a0: \u00abshort-lived radionuclides\u00bb). Nous mettons courte entre guillemets car c\u2019est le mot employ\u00e9 par les astrophysiciens, mais leur dur\u00e9e de vie para\u00eet tout de m\u00eame bien longue par rapport \u00e0 l\u2019\u00e9chelle d\u2019une vie. Le fer 60, dont la demi-vie est de 2,6 millions d\u2019ann\u00e9es, est par exemple consid\u00e9r\u00e9 comme un SLR. \u00ab\u00c0 l\u2019\u00e9chelle des temps astronomiques, cela reste tr\u00e8s rapide\u00bb, souligne Fr\u00e9d\u00e9ric Moynier, cosmochimiste \u00e0 l\u2019Institut de physique du globe de Paris. \u00abCela veut dire qu\u2019au bout de 26 millions d\u2019ann\u00e9es, soit dix demi-vies, la quantit\u00e9 de fer 60 a \u00e9t\u00e9 par dix fois divis\u00e9e par deux et qu\u2019il en reste donc moins d\u2019un milli\u00e8me (puisque 210=1024, NDLR).\u00bb<\/p>\n<p class=\"fig-paragraph\">La question est donc la suivante\u00a0: puisque ces \u00e9l\u00e9ments \u00e0 dur\u00e9e de vie courte disparaissent tr\u00e8s vite, d\u2019o\u00f9 peuvent-ils provenir\u00a0? Nous savons que les \u00e9toiles massives en produisent naturellement\u2026<\/p>\n<p class=\"fig-premium-paywall__infos\">\n        Cet article est r\u00e9serv\u00e9 aux abonn\u00e9s.        Il vous reste 79% \u00e0 d\u00e9couvrir.\n    <\/p>\n<p>                <img  data- alt=\"Le Figaro\" class=\"fig-img--complete fig-img\"\/><\/p>\n<p class=\"fig-premium-paywall__title\">Vente Flash<\/p>\n<p class=\"fig-premium-paywall__subtitle\">-50% sur l&rsquo;abonnement num\u00e9rique<\/p>\n<p class=\"fig-premium-paywall__connect\">\n                D\u00e9j\u00e0 abonn\u00e9\u00a0?                <a class=\"fig-premium-paywall__connect-link\" href=\"https:\/\/connect.lefigaro.fr\/login?client=horizon_web&amp;type=main&amp;redirect_uri=https%3A%2F%2Fwww.lefigaro.fr%2Fsciences%2Fla-terre-se-serait-formee-dans-un-bain-de-rayons-cosmiques-20251218\" data-js-gtm=\"{&quot;customCategorie&quot;: &quot;conversion&quot;, &quot;customAction&quot;: &quot;before_Landing_Connexion_paywall_auto&quot;, &quot;customLabel&quot;: &quot;bGVmaWdhcm8uZnJfXzFmMGRiMmM5LWRiM2MtNmMwNi04YzNiLWE5ZjRmNDJiM2IyNl9fQXJ0aWNsZQ==_La Terre se serait form\u00e9e dans un bain de rayons cosmiques_198&quot;, &quot;customIDSPE&quot;: &quot;bGVmaWdhcm8uZnJfXzFmMGRiMmM5LWRiM2MtNmMwNi04YzNiLWE5ZjRmNDJiM2IyNl9fQXJ0aWNsZQ==&quot;, &quot;event&quot;: &quot;customEventSPE&quot;}\" target=\"_blank\" rel=\"noopener\"><br \/>\n                    Connectez-vous<br \/>\n                <\/a>\n            <\/p>\n","protected":false},"excerpt":{"rendered":"D\u00c9CRYPTAGE &#8211; Une explosion d\u2019\u00e9toile survenue \u00e0 proximit\u00e9 du Syst\u00e8me solaire dans ses premiers millions d\u2019ann\u00e9es d\u2019existence expliquerait&hellip;\n","protected":false},"author":2,"featured_media":607314,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[48,1011,27,43,40,41,39,24901,42,44],"class_list":{"0":"post-607313","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-sciences-et-technologies","8":"tag-astronomie","9":"tag-fr","10":"tag-france","11":"tag-science","12":"tag-science-and-technology","13":"tag-sciences","14":"tag-sciences-et-technologies","15":"tag-systeme-solaire","16":"tag-technologies","17":"tag-technology"},"share_on_mastodon":{"url":"https:\/\/pubeurope.com\/@fr\/115740365500358851","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/fr\/wp-json\/wp\/v2\/posts\/607313","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/fr\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/fr\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/fr\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/fr\/wp-json\/wp\/v2\/comments?post=607313"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/fr\/wp-json\/wp\/v2\/posts\/607313\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/fr\/wp-json\/wp\/v2\/media\/607314"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/fr\/wp-json\/wp\/v2\/media?parent=607313"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/fr\/wp-json\/wp\/v2\/categories?post=607313"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/fr\/wp-json\/wp\/v2\/tags?post=607313"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}