{"id":661,"date":"2008-07-04T09:36:00","date_gmt":"2008-07-04T07:36:00","guid":{"rendered":"https:\/\/kids.esa.int\/can_et_hear_the_sounds_of_earth\/"},"modified":"2026-10-08T00:30:51","modified_gmt":"2026-10-07T22:30:51","slug":"can_et_hear_the_sounds_of_earth","status":"publish","type":"post","link":"https:\/\/kids.esa.int\/fr\/can_et_hear_the_sounds_of_earth\/","title":{"rendered":"Les extraterrestres entendent-ils les bruits \u00e9mis par la Terre ?"},"content":{"rendered":"<div class=\"lede\">\n<p>Les quatre satellites de la mission Cluster de l\u2019ESA ont d\u00e9couvert que la Terre et les autres plan\u00e8tes avaient un mode bien \u00e0 elles de signaler leur pr\u00e9sence au reste de la galaxie. Les messages, en fait de v\u00e9ritables cris d'appel, \u00e9mis par les plan\u00e8tes ne peuvent \u00eatre entendus et compris qu\u2019en utilisant de grands radiot\u00e9lescopes. Ainsi, une race extra-terrestre qui capterait les signaux radio naturels de la Terre entendrait une s\u00e9rie de stridulations et de sifflements, un peu comme ceux de R2-D2, le robot de la Guerre des \u00e9toiles.<\/p>\n<\/div>\n<p>\u00c0 l'heure actuelle, m\u00eame les t\u00e9lescopes les plus modernes ne sont pas assez puissants pour d\u00e9tecter des plan\u00e8tes de la taille de la Terre autour d'\u00e9toiles lointaines. Les astronomes extraterrestres sont confront\u00e9s au m\u00eame probl\u00e8me : chercher la Terre reviendrait \u00e0 chercher une aiguille dans une botte de foin. Cependant, les sursauts radio de notre plan\u00e8te \u2013 10 000 fois plus intenses que le signal radar militaire le plus puissant \u2013 signalent clairement la pr\u00e9sence de la Terre.<\/p>\n<figure class=\"wp-block-image size-natural\" data-width=\"400\" data-credit=\"ESA\" data-detail-url=\"https:\/\/www.esa.int\/Media\/Animations\/Auroral-2HQ\" data-licence=\"ESA Standard Licence\" data-licence-url=\"https:\/\/www.esa.int\/ESA_Multimedia\/Terms_and_conditions_of_use_of_images_and_videos_available_on_the_esa_website\"><img decoding=\"async\" loading=\"lazy\" style=\"max-width:100%;height:auto\" src=\"https:\/\/www.esa.int\/var\/esa\/storage\/images\/media\/animations\/auroral-2hq\/9257-5-eng-GB\/Auroral-2HQ.jpg\" alt=\"\"><\/figure>\n<p>Les chercheurs savent depuis les ann\u00e9es 70 que les plan\u00e8tes dot\u00e9es d\u2019un champ magn\u00e9tique (notamment la Terre, Jupiter et Saturne) \u00e9mettent des signaux radio forts. Ces \u00e9missions sont g\u00e9n\u00e9r\u00e9es bien au-dessus de chaque plan\u00e8te par les particules solaires qui sont \u00e0 l\u2019origine des aurores qui \u00e9clairent le ciel sous-jacent. Jusqu\u2019\u00e0 aujourd\u2019hui, les astronomes pensaient que ces ondes radio voyageaient dans l\u2019espace en format un c\u00f4ne s\u2019\u00e9largissant sans fin un peu comme la lumi\u00e8re d\u2019une lampe torche. Gr\u00e2ce \u00e0 Cluster, nous savons maintenant que ce n\u2019est pas vrai.<\/p>\n<p>Les rafales d\u2019ondes radio qu'ont essuy\u00e9es \u00e0 tour de r\u00f4le les satellites ont permis aux scientifiques d\u2019en calculer la position et l\u2019emplacement. Ils ont ainsi remarqu\u00e9 que les signaux voyageaient dans l\u2019espace en faisceau \u00e9troit, ce qui permet d\u2019en localiser bien plus facilement l\u2019origine. \u00c0 l\u2019avenir, nous pourrons peut-\u00eatre d\u00e9couvrir des mondes extraterrestres en captant leurs sifflements et stridulations.<\/p>","protected":false},"excerpt":{"rendered":"<p>ESA\u2019s four Cluster spacecraft have found that Earth and other planets have a way of shouting \u201cI\u2019m here!\u201d to the rest of the Galaxy. However, the messages from the planets [&hellip;]<\/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\/08\/the_cluster_constellation\/17863826-3-eng-GB\/The_Cluster_constellation.jpg","esa_banner_description":"The Cluster constellation","esa_banner_credit":"ESA","esa_banner_licence":"ESA Standard Licence","esa_banner_detail_url":"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2002\/08\/The_Cluster_constellation","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":[],"panel":[],"language":[],"age":[],"duration":[],"resource_type":[],"audience":[],"wf_post_folders":[],"class_list":["post-661","post","type-post","status-publish","format-standard","hentry","category-are-we-alone","category-learn","category-life-in-space"],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/posts\/661","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=661"}],"version-history":[{"count":5,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/posts\/661\/revisions"}],"predecessor-version":[{"id":4616,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/posts\/661\/revisions\/4616"}],"wp:attachment":[{"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/media?parent=661"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/categories?post=661"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/tags?post=661"},{"taxonomy":"panel","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/panel?post=661"},{"taxonomy":"language","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/language?post=661"},{"taxonomy":"age","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/age?post=661"},{"taxonomy":"duration","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/duration?post=661"},{"taxonomy":"resource_type","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/resource_type?post=661"},{"taxonomy":"audience","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/audience?post=661"},{"taxonomy":"wf_post_folders","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/wf_post_folders?post=661"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}