{"id":1133,"date":"2004-11-16T08:14:00","date_gmt":"2004-11-16T07:14:00","guid":{"rendered":"https:\/\/kids.esa.int\/planets_and_moons_life_on_earth\/"},"modified":"2026-10-08T00:36:23","modified_gmt":"2026-10-07T22:36:23","slug":"planets_and_moons_life_on_earth","status":"publish","type":"post","link":"https:\/\/kids.esa.int\/fr\/planets_and_moons_life_on_earth\/","title":{"rendered":"La vie sur la terre"},"content":{"rendered":"
\n

L'\u00e9tude des fossiles pr\u00e9sents dans les roches anciennes nous apprend que la vie est probablement apparue il y a environ 4 milliards d'ann\u00e9es, alors que la Terre \u00e9tait encore tr\u00e8s jeune. Personne ne sait comment la vie est apparue sur Terre. La plupart des scientifiques pensent qu'elle a pris naissance dans l'eau liquide. Mais s'agissait-il de mares \u00e0 la surface, souterraines, ou au fond des oc\u00e9ans, l\u00e0 o\u00f9 l'activit\u00e9 volcanique forme des sources chaudes ?<\/p>\n<\/div>\n

Des exp\u00e9riences montrent que les \u00e9l\u00e9ments chimiques constitutifs de la vie peuvent se former dans l'espace ou sur Terre. Bon nombre d'entre eux ont sans doute \u00e9t\u00e9 apport\u00e9s sur Terre par des m\u00e9t\u00e9orites et des com\u00e8tes. D'une mani\u00e8re ou d'une autre, ces compos\u00e9s chimiques \u2018 organiques \u2019 simples se sont assembl\u00e9s pour former des mol\u00e9cules plus complexes. C'est alors qu'ils ont commenc\u00e9 \u00e0 se reproduire et \u00e0 se d\u00e9velopper.<\/p>\n

\"Dry
Terre s\u00e8che<\/figcaption><\/figure>\n

Ce que nous savons, c\u2019est qu\u2019une fois qu\u2019elle a commenc\u00e9, la vie est incroyablement rude. Des bact\u00e9ries vivantes ont \u00e9t\u00e9 d\u00e9couvertes dans les glaces de l\u2019Antarctique, dans de l\u2019eau bouillante et \u00e0 l\u2019int\u00e9rieur de roches situ\u00e9es jusqu\u2019\u00e0 cinq kilom\u00e8tres sous terre. Nous savons \u00e9galement que ces organismes peuvent survivre pendant des ann\u00e9es dans l\u2019environnement hostile de l\u2019espace.<\/p>\n

Une fois que les plantes se sont r\u00e9pandues, de grandes quantit\u00e9s d'oxyg\u00e8ne ont \u00e9t\u00e9 lib\u00e9r\u00e9es dans l'air. La Terre est ainsi devenue la seule plan\u00e8te de notre syst\u00e8me solaire \u00e0 poss\u00e9der une atmosph\u00e8re riche en oxyg\u00e8ne. En recherchant de l'oxyg\u00e8ne sur d'autres mondes, nous pourrions un jour trouver des traces de vie extraterrestre.<\/p>","protected":false},"excerpt":{"rendered":"

Studies of fossils in ancient rocks tell us that life probably began about 4 billion years ago, when the Earth was very young. No one knows how life began on […]<\/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\/dna_s_famous_double-helix_structure3\/17902899-2-eng-GB\/DNA_s_famous_double-helix_structure.jpg","esa_banner_description":"DNA's famous double-helix structure","esa_banner_credit":"ESA 2003. Illustration by Medialab.","esa_banner_licence":"ESA Standard Licence","esa_banner_detail_url":"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2003\/05\/DNA_s_famous_double-helix_structure3","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":[10,11,12],"tags":[2],"panel":[],"language":[],"age":[],"duration":[],"resource_type":[],"audience":[],"wf_post_folders":[],"class_list":["post-1133","post","type-post","status-publish","format-standard","hentry","category-learn","category-our-universe","category-planets-and-moons","tag-background-article"],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/posts\/1133","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=1133"}],"version-history":[{"count":5,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/posts\/1133\/revisions"}],"predecessor-version":[{"id":4865,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/posts\/1133\/revisions\/4865"}],"wp:attachment":[{"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/media?parent=1133"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/categories?post=1133"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/tags?post=1133"},{"taxonomy":"panel","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/panel?post=1133"},{"taxonomy":"language","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/language?post=1133"},{"taxonomy":"age","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/age?post=1133"},{"taxonomy":"duration","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/duration?post=1133"},{"taxonomy":"resource_type","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/resource_type?post=1133"},{"taxonomy":"audience","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/audience?post=1133"},{"taxonomy":"wf_post_folders","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/wf_post_folders?post=1133"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}