{"id":1031,"date":"2005-05-02T12:13:00","date_gmt":"2005-05-02T10:13:00","guid":{"rendered":"https:\/\/kids.esa.int\/radar_to_reveal_hidden_mars\/"},"modified":"2026-10-08T00:35:05","modified_gmt":"2026-10-07T22:35:05","slug":"radar_to_reveal_hidden_mars","status":"publish","type":"post","link":"https:\/\/kids.esa.int\/fr\/radar_to_reveal_hidden_mars\/","title":{"rendered":"Un radar pour r\u00e9v\u00e9ler la face cach\u00e9e de Mars"},"content":{"rendered":"
\n

Un nouveau chapitre dans l\u2019exploration de Mars est sur le point de s\u2019ouvrir. Apr\u00e8s une longue attente, le radar MARSIS embarqu\u00e9 sur la sonde Mars Express de l\u2019ESA va pouvoir entrer en action.<\/p>\n<\/div>\n

MARSIS est le premier instrument \u00e0 avoir \u00e9t\u00e9 con\u00e7u pour aller sonder sous la surface rouge\u00e2tre de la Plan\u00e8te rouge en \u00e9mettant des signaux radio basse fr\u00e9quence.<\/p>\n

La plupart de ces signaux rebondiront tout de suite sur la surface, mais quelques-uns parviendront \u00e0 percer le sol pour ensuite rebondir depuis les couches de la subsurface.<\/p>\n

En analysant les \u00e9chos, les scientifiques esp\u00e8rent d\u00e9couvrir de la glace ou de l\u2019eau souterraine. Cet \u00e9l\u00e9ment serait capital quand on sait que la pr\u00e9sence d\u2019eau est souvent associ\u00e9e \u00e0 la vie.<\/p>\n

MARSIS sondera \u00e9galement les couches rocheuses jusqu\u2019\u00e0 une profondeur de plusieurs kilom\u00e8tres et mesurera la hauteur des montagnes et des vall\u00e9es.<\/p>\n

\"MARSIS
Antenne principale de MARSIS<\/figcaption><\/figure>\n

Mais avant tout cela, les trois segments (similaires \u00e0 des m\u00e2ts) qui constituent le radar doivent \u00eatre d\u00e9ploy\u00e9s. Ils auraient d\u00fb l\u2019\u00eatre en avril 2004, mais juste avant la date pr\u00e9vue, est apparu un risque de rebond des antennes, potentiellement dommageable pour la sonde.<\/p>\n

Comme nous l\u2019explique John Reddy de l\u2019ESA, \u00ab Un tel d\u00e9ploiement ne peut \u00eatre effectu\u00e9 sur Terre. C\u2019est pourquoi, \u00e0 moins de faire des essais dans l\u2019espace, nous ne pouvons compter que sur des simulations informatiques. \u00bb<\/p>\n

Apr\u00e8s analyse minutieuse des risques, l\u2019ESA a d\u00e9cid\u00e9 de donner son feu vert pour l\u2019exp\u00e9rience. Les deux m\u00e2ts de 20 m de long seront d\u00e9ploy\u00e9s en premier, suivi par le m\u00e2t de 7 m quelques jours plus tard. Cette op\u00e9ration devrait se d\u00e9rouler entre les 4 et 12 mai.<\/p>\n

Une fois le d\u00e9ploiement effectu\u00e9, MARSIS proc\u00e8dera \u00e0 trois semaines de tests. Le travail du radar pourra alors commencer.<\/p>","protected":false},"excerpt":{"rendered":"

A new chapter in the exploration of Mars is about to begin. After a long delay, the MARSIS radar instrument on board ESA\u2019s Mars Express orbiter is about to swing […]<\/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\/2001\/08\/marsis_prospecting_for_water2\/17863678-3-eng-GB\/MARSIS_prospecting_for_water.jpg","esa_banner_description":"MARSIS prospecting for water","esa_banner_credit":"ESA","esa_banner_licence":"ESA Standard Licence","esa_banner_detail_url":"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2001\/08\/MARSIS_prospecting_for_water2","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":[],"panel":[],"language":[],"age":[],"duration":[],"resource_type":[],"audience":[],"wf_post_folders":[],"class_list":["post-1031","post","type-post","status-publish","format-standard","hentry","category-learn","category-our-universe","category-planets-and-moons"],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/posts\/1031","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=1031"}],"version-history":[{"count":4,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/posts\/1031\/revisions"}],"predecessor-version":[{"id":4806,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/posts\/1031\/revisions\/4806"}],"wp:attachment":[{"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/media?parent=1031"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/categories?post=1031"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/tags?post=1031"},{"taxonomy":"panel","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/panel?post=1031"},{"taxonomy":"language","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/language?post=1031"},{"taxonomy":"age","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/age?post=1031"},{"taxonomy":"duration","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/duration?post=1031"},{"taxonomy":"resource_type","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/resource_type?post=1031"},{"taxonomy":"audience","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/audience?post=1031"},{"taxonomy":"wf_post_folders","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/wf_post_folders?post=1031"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}