{"id":1119,"date":"2004-11-15T13:46:00","date_gmt":"2004-11-15T12:46:00","guid":{"rendered":"https:\/\/kids.esa.int\/the_birth_of_galaxies\/"},"modified":"2026-10-08T00:36:12","modified_gmt":"2026-10-07T22:36:12","slug":"the_birth_of_galaxies","status":"publish","type":"post","link":"https:\/\/kids.esa.int\/fr\/the_birth_of_galaxies\/","title":{"rendered":"La naissance des Galaxies"},"content":{"rendered":"
\n

Nous ne pouvons rien voir de ce qui s'est pass\u00e9 au cours des 300 000 premi\u00e8res ann\u00e9es de l'Univers. Les scientifiques tentent de le d\u00e9terminer \u00e0 partir de leurs connaissances sur les particules atomiques et de mod\u00e8les informatiques.<\/p>\n<\/div>\n

La seule preuve directe du Big Bang lui-m\u00eame est une lueur \u00e0 peine visible dans l'espace. Les sondes et les t\u00e9lescopes envoy\u00e9s par ballons l'observent sous la forme d'un m\u00e9lange diffus de gaz l\u00e9g\u00e8rement plus chaud et plus froid tout autour de nous. Ces diff\u00e9rentes ondulations indiquent \u00e9galement o\u00f9 se trouvent les nuages d'hydrog\u00e8ne l\u00e9g\u00e8rement plus denses.<\/p>\n

Apr\u00e8s plusieurs millions d'ann\u00e9es, les zones denses se sont transform\u00e9es en mati\u00e8re \u00e0 cause de leur plus forte gravit\u00e9. Finalement, pr\u00e8s de 100 millions d\u2019ann\u00e9es apr\u00e8s le Big Bang, le gaz s'est suffisamment r\u00e9chauff\u00e9 et densifi\u00e9 pour que naissent les premi\u00e8res \u00e9toiles.<\/p>\n

Les nouvelles \u00e9toiles naissaient 10 fois plus vite que dans notre Univers actuel. D'\u00e9normes amas d'\u00e9toiles constitu\u00e8rent bient\u00f4t les premi\u00e8res galaxies.<\/p>\n

\"Hubble's
La toute nouvelle cam\u00e9ra du t\u00e9lescope Hubble observe un foyer de formation stellaire<\/figcaption><\/figure>\n

Le T\u00e9lescope Spatial Hubble ainsi que les puissants t\u00e9lescopes au sol commencent maintenant \u00e0 d\u00e9couvrir des galaxies cr\u00e9\u00e9es pr\u00e8s d'un milliard d'ann\u00e9es apr\u00e8s le Big Bang. Ces petites galaxies \u00e9taient bien plus proches les unes des autres qu'elles ne le sont aujourd'hui. Les collisions \u00e9taient chose courante. Comme deux flammes s'attirant l'une l'autre, elles fusionn\u00e8rent pour former de plus grandes galaxies. C'est ainsi que notre Voie Lact\u00e9e est apparue.<\/p>","protected":false},"excerpt":{"rendered":"

We cannot see anything that happened during the first 300  000 years of the Universe. Scientists try to work it out from their knowledge of atomic particles and from computer […]<\/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\/2003\/05\/artist_s_impression_of_the_birth_of_our_galaxy2\/17907421-2-eng-GB\/Artist_s_impression_of_the_birth_of_our_Galaxy.jpg","esa_banner_description":"Artist's impression of the birth of our Galaxy","esa_banner_credit":"NASA and Adolf Schaller","esa_banner_licence":"ESA Standard Licence","esa_banner_detail_url":"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2003\/05\/Artist_s_impression_of_the_birth_of_our_Galaxy2","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":[10,11,19],"tags":[2],"panel":[],"language":[],"age":[],"duration":[],"resource_type":[],"audience":[],"wf_post_folders":[],"class_list":["post-1119","post","type-post","status-publish","format-standard","hentry","category-learn","category-our-universe","category-story-of-the-universe","tag-background-article"],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/posts\/1119","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=1119"}],"version-history":[{"count":4,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/posts\/1119\/revisions"}],"predecessor-version":[{"id":4856,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/posts\/1119\/revisions\/4856"}],"wp:attachment":[{"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/media?parent=1119"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/categories?post=1119"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/tags?post=1119"},{"taxonomy":"panel","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/panel?post=1119"},{"taxonomy":"language","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/language?post=1119"},{"taxonomy":"age","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/age?post=1119"},{"taxonomy":"duration","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/duration?post=1119"},{"taxonomy":"resource_type","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/resource_type?post=1119"},{"taxonomy":"audience","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/audience?post=1119"},{"taxonomy":"wf_post_folders","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/wf_post_folders?post=1119"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}