{"id":953,"date":"2004-11-19T08:31:00","date_gmt":"2004-11-19T07:31:00","guid":{"rendered":"https:\/\/kids.esa.int\/telltale_signs\/"},"modified":"2026-10-08T00:34:10","modified_gmt":"2026-10-07T22:34:10","slug":"telltale_signs","status":"publish","type":"post","link":"https:\/\/kids.esa.int\/fr\/telltale_signs\/","title":{"rendered":"Indices"},"content":{"rendered":"
\n

La Terre est le seul lieu connu qui accueille la vie. Qu'est-ce qui la rend si particuli\u00e8re? La pr\u00e9sence d'eau liquide est un facteur essentiel.<\/p>\n<\/div>\n

La Terre est le seul endroit de notre syst\u00e8me solaire \u00e0 poss\u00e9der de vastes oc\u00e9ans \u00e0 sa surface. Cela s'explique par le fait qu'elle se trouve dans la \u2018 zone Goldilocks \u2019.<\/p>\n

Venus est trop pr\u00e8s du soleil et trop chaude. Mars est trop \u00e9loign\u00e9e et trop froide. La Terre est exactement \u00e0 la bonne distance et \u00e0 la bonne temp\u00e9rature.<\/p>\n

Pourrait-il exister des \u2018 Terres \u2019 en orbite autour d\u2019autres \u00e9toiles ? Comment pourrions-nous les reconna\u00eetre ? La premi\u00e8re chose \u00e0 faire est de mesurer la temp\u00e9rature d\u2019une plan\u00e8te. Il faudrait \u00e9galement disposer de preuves indiquant que l\u2019eau y est abondante.<\/p>\n

Nous devons ensuite rechercher des gaz tels que l'oxyg\u00e8ne et le m\u00e9thane. Ces gaz sont lib\u00e9r\u00e9s dans l'atmosph\u00e8re par les cr\u00e9atures vivantes.<\/p>\n

Les futures missions chercheront ces \u2018 biomarqueurs \u2019 dans des milliers de syst\u00e8mes stellaires. Bien qu\u2019elles ne d\u00e9tectent pas directement l\u2019oxyg\u00e8ne, elles \u2018 verront \u2019 l\u2019ozone, une forme d\u2019oxyg\u00e8ne. Elles d\u00e9tecteront \u00e9galement le dioxyde de carbone, l\u2019eau et, dans certains cas, le m\u00e9thane.<\/p>","protected":false},"excerpt":{"rendered":"

Earth is the only place we know that supports life. What makes it so special? One key factor is the presence of liquid water. Life on Earth seems to have […]<\/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\/2002\/01\/planet_earth_as_seen_by_the_apollo_17_astronauts2\/17863973-3-eng-GB\/Planet_Earth_as_seen_by_the_Apollo_17_astronauts.jpg","esa_banner_description":"Planet Earth as seen by the Apollo 17 astronauts","esa_banner_credit":"NASA","esa_banner_licence":"ESA Standard Licence","esa_banner_detail_url":"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2002\/01\/Planet_Earth_as_seen_by_the_Apollo_17_astronauts2","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":[14,10,13],"tags":[2],"panel":[],"language":[],"age":[],"duration":[],"resource_type":[],"audience":[],"wf_post_folders":[],"class_list":["post-953","post","type-post","status-publish","format-standard","hentry","category-are-we-alone","category-learn","category-life-in-space","tag-background-article"],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/posts\/953","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=953"}],"version-history":[{"count":1,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/posts\/953\/revisions"}],"predecessor-version":[{"id":2096,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/posts\/953\/revisions\/2096"}],"wp:attachment":[{"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/media?parent=953"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/categories?post=953"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/tags?post=953"},{"taxonomy":"panel","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/panel?post=953"},{"taxonomy":"language","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/language?post=953"},{"taxonomy":"age","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/age?post=953"},{"taxonomy":"duration","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/duration?post=953"},{"taxonomy":"resource_type","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/resource_type?post=953"},{"taxonomy":"audience","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/audience?post=953"},{"taxonomy":"wf_post_folders","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/wf_post_folders?post=953"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}