{"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\/cs\/phobos_and_deimos\/","title":{"rendered":"Fobos a Deimos"},"content":{"rendered":"
\n

V roce 1877 objevil americk\u00fd astronom Asaph Hall dva mal\u00e9 m\u011bs\u00edce ob\u00edhaj\u00edc\u00ed kolem planety Mars. Byly pojmenov\u00e1ny Phobos (Strach) a Deimos (Panika). I po v\u00edce ne\u017e 130 letech se v\u011bdci st\u00e1le sna\u017e\u00ed odhalit tajemstv\u00ed t\u011bchto m\u011bs\u00edc\u016f.<\/p>\n<\/div>\n

Mohou to b\u00fdt asteroidy \u2013 mal\u00e9 horniny, kter\u00e9 zbyly po vzniku planet \u2013 a kter\u00e9 byly zachyceny Marsem.<\/p>\n

Oba m\u011bs\u00edce jsou \u010dern\u011bj\u0161\u00ed ne\u017e uhl\u00ed a vypadaj\u00ed jako rozma\u010dkan\u00e9 brambory. Phobos m\u00e1 v nej\u0161ir\u0161\u00edm m\u00edst\u011b pr\u016fm\u011br 27 km a na jedn\u00e9 stran\u011b se nach\u00e1z\u00ed velk\u00fd impaktn\u00ed kr\u00e1ter. Kolem Marsu oblet\u00ed t\u0159ikr\u00e1t za jeden mar\u0165ansk\u00fd den.<\/p>\n

Deimos je je\u0161t\u011b men\u0161\u00ed \u2013 pat\u0159\u00ed k nejmen\u0161\u00edm m\u011bs\u00edc\u016fm ve slune\u010dn\u00ed soustav\u011b. Nach\u00e1z\u00ed se d\u00e1le od Marsu, tak\u017ee mu jeden ob\u011bh kolem planety trv\u00e1 n\u011bco m\u00e1lo p\u0159es jeden den.<\/p>\n

D\u00edky jejich mal\u00fdm rozm\u011br\u016fm je gravitace na obou m\u011bs\u00edc\u00edch velmi slab\u00e1. Astronaut stoj\u00edc\u00ed na Phobosu by byl 1000kr\u00e1t leh\u010d\u00ed ne\u017e na Zemi. Jak\u00fdkoli v\u011bt\u0161\u00ed skok by mohl m\u00edt za n\u00e1sledek, \u017ee by astronaut odlet\u011bl do vesm\u00edru!<\/p>\n

Bl\u00edzk\u00e9 pr\u016flety sondy Mars Express agentury ESA poskytly vod\u00edtka k tomu, z \u010deho jsou tyto planety slo\u017eeny a odkud poch\u00e1zej\u00ed.<\/p>\n

Mars Express je jedin\u00e1 kosmick\u00e1 sonda, kter\u00e1 v sou\u010dasn\u00e9 dob\u011b ob\u00edh\u00e1 kolem Rud\u00e9 planety na vysoce eliptick\u00e9 (vejcovit\u00e9) ob\u011b\u017en\u00e9 dr\u00e1ze. Tato dr\u00e1ha ji vede p\u0159es ob\u011b\u017enou dr\u00e1hu Phobosu, co\u017e j\u00ed umo\u017e\u0148uje pozorovat v\u0161echny strany tohoto mal\u00e9ho m\u011bs\u00edce. (Stejn\u011b jako M\u011bs\u00edc Zem\u011b i Phobos v\u017edy obrac\u00ed ke sv\u00e9 mate\u0159sk\u00e9 planet\u011b stejnou stranou.) Mezi 23. \u010dervencem a 15. z\u00e1\u0159\u00edm 2008 provedla sonda Mars Express osm pr\u016flet\u016f kolem Phobosu, p\u0159i\u010dem\u017e se k n\u011bmu p\u0159ibli\u017eovala na vzd\u00e1lenost od 4 500 km a\u017e po pouh\u00fdch 93 km.<\/p>\n

Z\u00e1b\u011bry zbl\u00edzka ukazuj\u00ed, \u017ee Phobos, v\u011bt\u0161\u00ed z obou m\u011bs\u00edc\u016f, je vesm\u00edrn\u00e1 sk\u00e1la ve tvaru brambory o rozm\u011brech pouh\u00fdch 27 km \u00d7 22 km \u00d7 19 km. Je velmi tmav\u00fd \u2013 \u010dern\u011bj\u0161\u00ed ne\u017e uhl\u00ed \u2013 a pokryt\u00fd \u010detn\u00fdmi kr\u00e1tery. Pe\u010dliv\u00fdm sledov\u00e1n\u00edm toho, jak Phobos p\u0159i ka\u017ed\u00e9m pr\u016fletu p\u016fsob\u00ed gravita\u010dn\u00ed silou na sondu Mars Express, v\u011bdci zjistili, \u017ee tento m\u011bs\u00edc nen\u00ed p\u0159\u00edli\u0161 hust\u00fd. T\u00e9m\u011b\u0159 jist\u011b se jedn\u00e1 o \u2018hromadu suti\u2019 \u2013 slo\u017eenou z mnoha kus\u016f horniny, kter\u00e9 dr\u017e\u00ed pohromad\u011b gravitace \u2013 sp\u00ed\u0161e ne\u017e o jedin\u00fd pevn\u00fd objekt.<\/p>\n

Studie sondy Mars Express nazna\u010duj\u00ed, \u017ee Phobos a Deimos mohly b\u00fdt kdysi asteroidy, kter\u00e9 ob\u00edhaly kolem Slunce mezi Marsem a Jupiterem. Nikdo v\u0161ak zat\u00edm nedok\u00e1\u017ee vysv\u011btlit, jak byly zachyceny Marsem a jak se ocitly na \u2018norm\u00e1ln\u00edch\u2019 ob\u011b\u017en\u00fdch drah\u00e1ch nad jeho rovn\u00edkem.<\/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\/cs\/wp-json\/wp\/v2\/posts\/921","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/kids.esa.int\/cs\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/kids.esa.int\/cs\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/kids.esa.int\/cs\/wp-json\/wp\/v2\/users\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/kids.esa.int\/cs\/wp-json\/wp\/v2\/comments?post=921"}],"version-history":[{"count":1,"href":"https:\/\/kids.esa.int\/cs\/wp-json\/wp\/v2\/posts\/921\/revisions"}],"predecessor-version":[{"id":2064,"href":"https:\/\/kids.esa.int\/cs\/wp-json\/wp\/v2\/posts\/921\/revisions\/2064"}],"wp:attachment":[{"href":"https:\/\/kids.esa.int\/cs\/wp-json\/wp\/v2\/media?parent=921"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/kids.esa.int\/cs\/wp-json\/wp\/v2\/categories?post=921"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/kids.esa.int\/cs\/wp-json\/wp\/v2\/tags?post=921"},{"taxonomy":"panel","embeddable":true,"href":"https:\/\/kids.esa.int\/cs\/wp-json\/wp\/v2\/panel?post=921"},{"taxonomy":"language","embeddable":true,"href":"https:\/\/kids.esa.int\/cs\/wp-json\/wp\/v2\/language?post=921"},{"taxonomy":"age","embeddable":true,"href":"https:\/\/kids.esa.int\/cs\/wp-json\/wp\/v2\/age?post=921"},{"taxonomy":"duration","embeddable":true,"href":"https:\/\/kids.esa.int\/cs\/wp-json\/wp\/v2\/duration?post=921"},{"taxonomy":"resource_type","embeddable":true,"href":"https:\/\/kids.esa.int\/cs\/wp-json\/wp\/v2\/resource_type?post=921"},{"taxonomy":"audience","embeddable":true,"href":"https:\/\/kids.esa.int\/cs\/wp-json\/wp\/v2\/audience?post=921"},{"taxonomy":"wf_post_folders","embeddable":true,"href":"https:\/\/kids.esa.int\/cs\/wp-json\/wp\/v2\/wf_post_folders?post=921"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}