{"id":921,"date":"2004-11-15T16:12:00","date_gmt":"2004-11-15T15:12:00","guid":{"rendered":"https:\/\/kids.esa.int\/phobos_and_deimos\/"},"modified":"2026-10-08T00:33:48","modified_gmt":"2026-10-07T22:33:48","slug":"phobos_and_deimos","status":"publish","type":"post","link":"https:\/\/kids.esa.int\/da\/phobos_and_deimos\/","title":{"rendered":"Phobos og Deimos"},"content":{"rendered":"
\n

I 1877 opdagede den amerikanske astronom Asaph Hall to sm\u00e5 m\u00e5ner, der kredser om planeten Mars. De fik navnene Phobos (Frygt) og Deimos (Panik). Mere end 130 \u00e5r senere fors\u00f8ger forskerne stadig at l\u00f8se mysterierne omkring disse m\u00e5ner.<\/p>\n<\/div>\n

Det kan v\u00e6re asteroider \u2013 sm\u00e5 klippestykker, der er tilbage fra planeternes dannelse \u2013 som Mars har indfanget.<\/p>\n

Begge m\u00e5ner er sortere end kul og ligner smadrede kartofler. Phobos er 27 km i diameter p\u00e5 det bredeste sted og har et stort nedslagskrater p\u00e5 den ene side. Den kredser tre gange rundt om Mars p\u00e5 \u00e9n marsdag.<\/p>\n

Deimos er endnu mindre \u2013 en af de mindste m\u00e5ner i solsystemet. Den ligger l\u00e6ngere v\u00e6k fra Mars, s\u00e5 hver oml\u00f8bsbane omkring planeten tager lidt over en dag.<\/p>\n

Deres lille st\u00f8rrelse betyder, at tyngdekraften p\u00e5 begge m\u00e5ner er meget svag. En astronaut, der st\u00e5r p\u00e5 Phobos, ville opleve en tyngdekraft, der er 1000 gange svagere end p\u00e5 Jorden. Store spring kunne f\u00e5 astronauten til at flyve ud i rummet!<\/p>\n

T\u00e6tte forbiflyvninger foretaget af ESA\u2019s rumfart\u00f8j Mars Express har givet os en id\u00e9 om, hvad disse planeter best\u00e5r af, og hvor de stammer fra.<\/p>\n

Mars Express er det eneste rumfart\u00f8j, der i \u00f8jeblikket opererer omkring den R\u00f8de Planet, og som befinder sig i en st\u00e6rkt elliptisk (\u00e6ggeformet) bane. Denne bane f\u00f8rer den p\u00e5 tv\u00e6rs af Phobos\u2019 bane, hvilket g\u00f8r det muligt at se alle sider af den lille m\u00e5ne. (Ligesom Jordens M\u00e5ne vender Phobos altid den samme side mod den n\u00e6rliggende planet.) Mellem den 23. juli og den 15. september 2008 gennemf\u00f8rte Mars Express otte forbiflyvninger af Phobos, hvor den susede forbi i afstande fra 4.500 km til kun 93 km.<\/p>\n

N\u00e6rbilleder viser, at Phobos, den st\u00f8rste m\u00e5ne, er en kartoffelformet rumklippe, der kun m\u00e5ler 27 km x 22 km x 19 km. Den er meget m\u00f8rk \u2013 sort som kul \u2013 og er d\u00e6kket af utallige kratere. Ved n\u00f8je at f\u00f8lge den m\u00e5de, hvorp\u00e5 Phobos tr\u00e6kker i Mars Express under hver forbiflyvning, har forskerne fundet ud af, at m\u00e5nen ikke er s\u00e6rlig t\u00e6t. Den er n\u00e6sten helt sikkert en \u2018stenbunke\u2019 \u2013 best\u00e5ende af mange stykker sten, der holdes sammen af tyngdekraften \u2013 snarere end et enkelt, fast objekt.<\/p>\n

Unders\u00f8gelser fra Mars Express tyder p\u00e5, at Phobos og Deimos m\u00e5ske engang var asteroider, der kredsede om Solen mellem Mars og Jupiter. Ingen kan dog endnu forklare, hvordan de blev indfanget af Mars og endte i \u2018normale\u2019 baner over planetens \u00e6kvator.<\/p>","protected":false},"excerpt":{"rendered":"

In 1877, the American astronomer Asaph Hall discovered two small moons circling the planet Mars. They were named Phobos (Fear) and Deimos (Panic). More than 130 years later, scientists are […]<\/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\/2004\/11\/phobos_in_colour_close-up2\/17881549-2-eng-GB\/Phobos_in_colour_close-up.jpg","esa_banner_description":"Phobos in colour, close-up","esa_banner_credit":"ESA\/DLR\/FU Berlin (G. Neukum)","esa_banner_licence":"ESA Standard Licence","esa_banner_detail_url":"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2004\/11\/Phobos_in_colour_close-up2","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-921","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\/da\/wp-json\/wp\/v2\/posts\/921","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/users\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/comments?post=921"}],"version-history":[{"count":1,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/posts\/921\/revisions"}],"predecessor-version":[{"id":2064,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/posts\/921\/revisions\/2064"}],"wp:attachment":[{"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/media?parent=921"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/categories?post=921"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/tags?post=921"},{"taxonomy":"panel","embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/panel?post=921"},{"taxonomy":"language","embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/language?post=921"},{"taxonomy":"age","embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/age?post=921"},{"taxonomy":"duration","embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/duration?post=921"},{"taxonomy":"resource_type","embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/resource_type?post=921"},{"taxonomy":"audience","embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/audience?post=921"},{"taxonomy":"wf_post_folders","embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/wf_post_folders?post=921"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}