{"id":931,"date":"2004-11-15T14:32:00","date_gmt":"2004-11-15T13:32:00","guid":{"rendered":"https:\/\/kids.esa.int\/dwarfs_and_supergiants\/"},"modified":"2026-10-08T00:33:54","modified_gmt":"2026-10-07T22:33:54","slug":"dwarfs_and_supergiants","status":"publish","type":"post","link":"https:\/\/kids.esa.int\/fr\/dwarfs_and_supergiants\/","title":{"rendered":"Les naines et les super g\u00e9antes"},"content":{"rendered":"
\n

Le Soleil est une \u00e9toile. Comme la plupart des \u00e9toiles, le Soleil est une boule de gaz tr\u00e8s chaud qui produit d'\u00e9normes quantit\u00e9s de lumi\u00e8re, de chaleur et d'autres rayonnements. Ces rayonnements sont le r\u00e9sultat des r\u00e9actions nucl\u00e9aires dans le noyau. C'est comme si des millions de bombes \u00e0 hydrog\u00e8ne explosaient chaque seconde.<\/p>\n<\/div>\n

Il existe de nombreux types d'\u00e9toiles. Les \u00e9toiles rouges sont les plus froides, avec des temp\u00e9ratures de surface avoisinant les 2 500 degr\u00e9s Celsius. Les \u00e9toiles bleu-blanc sont les plus chaudes, atteignant une temp\u00e9rature torride
40 000 degr\u00e9s. Les \u00e9toiles jaunes, comme le Soleil, se situent entre les deux, avec des temp\u00e9ratures de surface d'environ 5 500 degr\u00e9s.<\/p>\n

Les \u00e9toiles ont \u00e9galement de nombreuses tailles. Le Soleil a une taille moyenne. Il br\u00fble son hydrog\u00e8ne assez lentement, aussi peut-il continuer \u00e0 briller pendant 10 milliards d'ann\u00e9es. Certaines \u00e9toiles sont bien plus grosses et bien plus chaudes que le Soleil. La super g\u00e9ante rouge, Antares, est 800 fois plus grosse que le Soleil. Si elle se trouvait au centre de notre syst\u00e8me solaire, elle avalerait toutes les plan\u00e8tes qui s\u2019y trouvent, y compris la Terre. Comme des voitures grandes consommatrices de gaz, ces super g\u00e9antes consomment tout leur hydrog\u00e8ne et tout leur h\u00e9lium tr\u00e8s rapidement.<\/p>\n

Les \u00e9toiles les plus froides et dont la combustion est la plus lente sont les naines rouges. Celles-ci peuvent vivre plus de 10 000 milliards d'ann\u00e9es. Encore plus froides et plus petites, les naines brunes sont des \u2018 \u00e9toiles rat\u00e9es \u2019. Elles sont si froides \u2013 parfois \u00e0 peine quelques centaines de degr\u00e9s en surface \u2013 que leurs r\u00e9acteurs nucl\u00e9aires ne se mettent jamais en marche.<\/p>","protected":false},"excerpt":{"rendered":"

The Sun is a star. Like most stars, the Sun is a ball of very hot gas that gives off huge amounts of light, heat and other radiation. This radiation […]<\/p>\n","protected":false},"author":5,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"esa_banner_image":"https:\/\/www.esa.int\/var\/esa\/storage\/images\/esa_multimedia\/images\/2000\/09\/the_tycho_supernova2\/17865860-3-eng-GB\/The_Tycho_supernova.jpg","esa_banner_description":"The Tycho supernova","esa_banner_credit":"ESA","esa_banner_licence":"ESA Standard Licence","esa_banner_detail_url":"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2000\/09\/The_Tycho_supernova2","esa_external_url":"","esa_external_new_window":false,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_post_was_ever_published":true},"categories":[10,11,21],"tags":[2],"panel":[],"language":[],"age":[],"duration":[],"resource_type":[],"audience":[],"wf_post_folders":[],"class_list":["post-931","post","type-post","status-publish","format-standard","hentry","category-learn","category-our-universe","category-stars-and-galaxies","tag-background-article"],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/posts\/931","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/users\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/comments?post=931"}],"version-history":[{"count":1,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/posts\/931\/revisions"}],"predecessor-version":[{"id":2074,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/posts\/931\/revisions\/2074"}],"wp:attachment":[{"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/media?parent=931"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/categories?post=931"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/tags?post=931"},{"taxonomy":"panel","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/panel?post=931"},{"taxonomy":"language","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/language?post=931"},{"taxonomy":"age","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/age?post=931"},{"taxonomy":"duration","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/duration?post=931"},{"taxonomy":"resource_type","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/resource_type?post=931"},{"taxonomy":"audience","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/audience?post=931"},{"taxonomy":"wf_post_folders","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/wf_post_folders?post=931"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}