{"id":509,"date":"2004-11-16T10:36:00","date_gmt":"2004-11-16T09:36:00","guid":{"rendered":"https:\/\/kids.esa.int\/asteroids_the_minor_planets\/"},"modified":"2026-10-08T00:29:02","modified_gmt":"2026-10-07T22:29:02","slug":"asteroids_the_minor_planets","status":"publish","type":"post","link":"https:\/\/kids.esa.int\/fr\/asteroids_the_minor_planets\/","title":{"rendered":"Les ast\u00e9ro\u00efdes \u2013 les plan\u00e8tes mineures"},"content":{"rendered":"<div class=\"lede\">\n<p>Les ast\u00e9ro\u00efdes sont de petits corps rocheux issus de la formation des plan\u00e8tes, il y a 4,5 milliards d'ann\u00e9es. On les appelle souvent \u2018 plan\u00e8tes mineures \u2019.<\/p>\n<\/div>\n<p>On estime qu'il existe des milliards de ces morceaux de roche. La plupart d'entre eux se trouvent dans une \u2018 ceinture principale \u2019 en forme d'anneau, situ\u00e9e entre les orbites de Mars et de Jupiter. \u00c0 la limite int\u00e9rieure de cette ceinture principale, les ast\u00e9ro\u00efdes mettent environ trois ans \u00e0 effectuer une orbite autour du Soleil. Ceux qui se trouvent pr\u00e8s de la limite ext\u00e9rieure de la ceinture principale mettent deux fois plus de temps.<\/p>\n<p>Le mot \u2018 ast\u00e9ro\u00efde \u2019 signifie \u2018 semblable \u00e0 une \u00e9toile \u2019. On leur a donn\u00e9 ce nom car, dans la plupart des t\u00e9lescopes, ils n\u2019apparaissent que sous la forme de points lumineux. Au d\u00e9but du XXe si\u00e8cle, les astronomes les qualifiaient de \u2018 vermine du ciel \u2019. Ils \u00e9taient si nombreux qu'ils g\u00e2chaient les photographies de galaxies et de n\u00e9buleuses lointaines.<\/p>\n<p>Le plus grand des ast\u00e9ro\u00efdes, C\u00e9r\u00e8s, a \u00e9t\u00e9 d\u00e9couvert le premier. Il fut d\u00e9couvert par Giuseppi Piazzi \u00e0 Palerme, en Sicile, le 1er janvier 1801.<\/p>\n<p>Une seconde plan\u00e8te mineure, Pallas, fut d\u00e9couverte par Wilhelm Olbers en 1802. Elle fut suivie par Junon (1804) et Vesta (1807). Depuis 1847, pas une ann\u00e9e ne s'est pass\u00e9e sans que l'on ne d\u00e9couvre au moins un ast\u00e9ro\u00efde.<\/p>\n<nav class=\"related\" aria-label=\"\u00c0 lire \u00e9galement\">\n<h2 class=\"related__heading\">\u00c0 lire \u00e9galement<\/h2>\n<div class=\"grid related__grid\">\n<div class=\"grid-item\">\n<article class=\"card focuson agency\"><a class=\"card__link\" href=\"\/fr\/asteroider_de_smaa_planeter\/\"><\/p>\n<figure class=\"thumbnail\"><span class=\"dimmer\"><\/span><\/figure>\n<header class=\"entry\">\n<h3 class=\"heading\">danois<\/h3>\n<\/header>\n<p><\/a><\/article>\n<\/div>\n<div class=\"grid-item\">\n<article class=\"card focuson agency\"><a class=\"card__link\" href=\"\/fr\/planetoiden_-_de_kleine_planeten\/\"><\/p>\n<figure class=\"thumbnail\"><span class=\"dimmer\"><\/span><\/figure>\n<header class=\"entry\">\n<h3 class=\"heading\">n\u00e9erlandais<\/h3>\n<\/header>\n<p><\/a><\/article>\n<\/div>\n<div class=\"grid-item\">\n<article class=\"card focuson agency\"><a class=\"card__link\" href=\"\/fr\/asteroiden_-_die_kleinplaneten\/\"><\/p>\n<figure class=\"thumbnail\"><span class=\"dimmer\"><\/span><\/figure>\n<header class=\"entry\">\n<h3 class=\"heading\">Allemand<\/h3>\n<\/header>\n<p><\/a><\/article>\n<\/div>\n<div class=\"grid-item\">\n<article class=\"card focuson agency\"><a class=\"card__link\" href=\"\/fr\/asteroider_de_smaa_planetene\/\"><\/p>\n<figure class=\"thumbnail\"><span class=\"dimmer\"><\/span><\/figure>\n<header class=\"entry\">\n<h3 class=\"heading\">norv\u00e9gien<\/h3>\n<\/header>\n<p><\/a><\/article>\n<\/div>\n<div class=\"grid-item\">\n<article class=\"card focuson agency\"><a class=\"card__link\" href=\"\/fr\/asteroidy_czyli_planetoidy\/\"><\/p>\n<figure class=\"thumbnail\"><span class=\"dimmer\"><\/span><\/figure>\n<header class=\"entry\">\n<h3 class=\"heading\">polonais<\/h3>\n<\/header>\n<p><\/a><\/article>\n<\/div>\n<div class=\"grid-item\">\n<article class=\"card focuson agency\"><a class=\"card__link\" href=\"\/fr\/asteroider_smaaplaneterna\/\"><\/p>\n<figure class=\"thumbnail\"><span class=\"dimmer\"><\/span><\/figure>\n<header class=\"entry\">\n<h3 class=\"heading\">su\u00e9dois<\/h3>\n<\/header>\n<p><\/a><\/article>\n<\/div>\n<\/div>\n<\/nav>","protected":false},"excerpt":{"rendered":"<p>Asteroids are small, rocky bodies that have been left over from the formation of the planets 4.5 billion years ago. They are often known as &#8216;minor planets&#8217;. There are thought [&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\/2001\/07\/asteroid_243_ida_and_its_newly_discovered_moon_dactyl2\/17863270-3-eng-GB\/Asteroid_243_Ida_and_its_newly_discovered_moon_Dactyl.jpg","esa_banner_description":"Asteroid 243 Ida and its newly discovered moon, Dactyl","esa_banner_credit":"NASA","esa_banner_licence":"ESA Standard Licence","esa_banner_detail_url":"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2001\/07\/Asteroid_243_Ida_and_its_newly_discovered_moon_Dactyl2","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":[46,10,11],"tags":[2],"panel":[],"language":[],"age":[],"duration":[],"resource_type":[],"audience":[],"wf_post_folders":[],"class_list":["post-509","post","type-post","status-publish","format-standard","hentry","category-comets-and-meteors","category-learn","category-our-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\/509","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=509"}],"version-history":[{"count":1,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/posts\/509\/revisions"}],"predecessor-version":[{"id":1652,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/posts\/509\/revisions\/1652"}],"wp:attachment":[{"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/media?parent=509"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/categories?post=509"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/tags?post=509"},{"taxonomy":"panel","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/panel?post=509"},{"taxonomy":"language","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/language?post=509"},{"taxonomy":"age","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/age?post=509"},{"taxonomy":"duration","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/duration?post=509"},{"taxonomy":"resource_type","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/resource_type?post=509"},{"taxonomy":"audience","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/audience?post=509"},{"taxonomy":"wf_post_folders","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/wf_post_folders?post=509"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}