{"version":"1.0","provider_name":"AFRIK Management","provider_url":"https:\/\/afrikmanagement.com","author_name":"admin","author_url":"https:\/\/afrikmanagement.com\/index.php\/author\/wxrmg2xuqd\/","title":"N\u00e9buleuse plan\u00e9taire : qu'est-ce que c'est ? - AFRIK Management","type":"rich","width":600,"height":338,"html":"<blockquote class=\"wp-embedded-content\" data-secret=\"dF4v4EYvwL\"><a href=\"https:\/\/afrikmanagement.com\/index.php\/2023\/09\/25\/nebuleuse-planetaire-quest-ce-que-cest\/\">N\u00e9buleuse plan\u00e9taire : qu&#8217;est-ce que c&#8217;est ?<\/a><\/blockquote><iframe sandbox=\"allow-scripts\" security=\"restricted\" src=\"https:\/\/afrikmanagement.com\/index.php\/2023\/09\/25\/nebuleuse-planetaire-quest-ce-que-cest\/embed\/#?secret=dF4v4EYvwL\" width=\"600\" height=\"338\" title=\"\u00ab\u00a0N\u00e9buleuse plan\u00e9taire : qu&#8217;est-ce que c&#8217;est ?\u00a0\u00bb &#8212; AFRIK Management\" data-secret=\"dF4v4EYvwL\" frameborder=\"0\" marginwidth=\"0\" marginheight=\"0\" scrolling=\"no\" class=\"wp-embedded-content\"><\/iframe><script type=\"text\/javascript\">\n\/* <![CDATA[ *\/\n\/*! This file is auto-generated *\/\n!function(d,l){\"use strict\";l.querySelector&&d.addEventListener&&\"undefined\"!=typeof URL&&(d.wp=d.wp||{},d.wp.receiveEmbedMessage||(d.wp.receiveEmbedMessage=function(e){var t=e.data;if((t||t.secret||t.message||t.value)&&!\/[^a-zA-Z0-9]\/.test(t.secret)){for(var s,r,n,a=l.querySelectorAll('iframe[data-secret=\"'+t.secret+'\"]'),o=l.querySelectorAll('blockquote[data-secret=\"'+t.secret+'\"]'),c=new RegExp(\"^https?:$\",\"i\"),i=0;i<o.length;i++)o[i].style.display=\"none\";for(i=0;i<a.length;i++)s=a[i],e.source===s.contentWindow&&(s.removeAttribute(\"style\"),\"height\"===t.message?(1e3<(r=parseInt(t.value,10))?r=1e3:~~r<200&&(r=200),s.height=r):\"link\"===t.message&&(r=new URL(s.getAttribute(\"src\")),n=new URL(t.value),c.test(n.protocol))&&n.host===r.host&&l.activeElement===s&&(d.top.location.href=t.value))}},d.addEventListener(\"message\",d.wp.receiveEmbedMessage,!1),l.addEventListener(\"DOMContentLoaded\",function(){for(var e,t,s=l.querySelectorAll(\"iframe.wp-embedded-content\"),r=0;r<s.length;r++)(t=(e=s[r]).getAttribute(\"data-secret\"))||(t=Math.random().toString(36).substring(2,12),e.src+=\"#?secret=\"+t,e.setAttribute(\"data-secret\",t)),e.contentWindow.postMessage({message:\"ready\",secret:t},\"*\")},!1)))}(window,document);\n\/\/# sourceURL=https:\/\/afrikmanagement.com\/wp-includes\/js\/wp-embed.min.js\n\/* ]]> *\/\n<\/script>\n","thumbnail_url":"https:\/\/afrikmanagement.com\/wp-content\/uploads\/2023\/09\/nebulesue_chat_wikipedia_nasa.webp","thumbnail_width":1417,"thumbnail_height":1417,"description":"Les\u00a0n\u00e9buleuses\u00a0plan\u00e9taires sont nomm\u00e9es ainsi parce qu&#8217;autrefois, les\u00a0astronomes\u00a0les prenaient pour des plan\u00e8tes. Elles font partie des plus beaux objets\u00a0astrophysiques\u00a0que l&#8217;on peut admirer dans le cosmos avec un t\u00e9lescope. Ce sont de grands\u00a0nuages\u00a0de\u00a0gaz\u00a0cr\u00e9\u00e9s par des\u00a0\u00e9toiles g\u00e9antes\u00a0en fin de vie qui deviennent instables et se mettent \u00e0 \u00e9jecter leurs couches sup\u00e9rieures. Elles constituent finalement une enveloppe de gaz en expansion autour d&#8217;une naine blanche. Le rayonnement\u00a0ultraviolet\u00a0des \u00e9toiles mourantes, en excitant les\u00a0atomes\u00a0et\u00a0mol\u00e9cules\u00a0de ces nuages, est responsable de leurs\u00a0couleurs\u00a0si particuli\u00e8res. Les n\u00e9buleuses plan\u00e9taires se dispersent en 50.000 ans, voire moins. Extrait du documentaire\u00a0Du Big bang au Vivant. Jean-Pierre Luminet parle de l&#8217;\u00e9volution des \u00e9toiles de [&hellip;]"}