{"id":1005,"date":"2004-11-15T13:50:00","date_gmt":"2004-11-15T12:50:00","guid":{"rendered":"https:\/\/kids.esa.int\/what_is_space\/"},"modified":"2026-10-08T00:34:45","modified_gmt":"2026-10-07T22:34:45","slug":"what_is_space","status":"publish","type":"post","link":"https:\/\/kids.esa.int\/cs\/what_is_space\/","title":{"rendered":"Co je to vesm\u00edr?"},"content":{"rendered":"<div class=\"lede\">\n<p>Ve vesm\u00edru nikdo nesly\u0161\u00ed tv\u016fj v\u00fdk\u0159ik. Je to proto, \u017ee ve vesm\u00edru nen\u00ed vzduch \u2013 je to vakuum. Zvukov\u00e9 vlny se vakuem \u0161\u00ed\u0159it nemohou.<\/p>\n<\/div>\n<p>\u2018Vesm\u00edr\u2019 za\u010d\u00edn\u00e1 p\u0159ibli\u017en\u011b 100 km nad Zem\u00ed, kde kon\u010d\u00ed vrstva vzduchu obklopuj\u00edc\u00ed na\u0161i planetu. Bez vzduchu, kter\u00fd by rozptyloval slune\u010dn\u00ed sv\u011btlo a vytv\u00e1\u0159el modrou oblohu, se vesm\u00edr jev\u00ed jako \u010dern\u00e1 p\u0159ikr\u00fdvka poset\u00e1 hv\u011bzdami.<\/p>\n<p>Vesm\u00edr se obvykle pova\u017euje za zcela pr\u00e1zdn\u00fd. To v\u0161ak nen\u00ed pravda. Obrovsk\u00e9 mezery mezi hv\u011bzdami a planetami jsou vypln\u011bny obrovsk\u00fdm mno\u017estv\u00edm \u0159\u00eddce rozpt\u00fdlen\u00e9ho plynu a prachu. I ty nejpr\u00e1zdn\u011bj\u0161\u00ed \u010d\u00e1sti vesm\u00edru obsahuj\u00ed alespo\u0148 n\u011bkolik set atom\u016f nebo molekul na metr krychlov\u00fd.<\/p>\n<p>Vesm\u00edr je tak\u00e9 pln\u00fd mnoha druh\u016f z\u00e1\u0159en\u00ed, kter\u00e9 jsou pro astronauty nebezpe\u010dn\u00e9. Velk\u00e1 \u010d\u00e1st tohoto infra\u010derven\u00e9ho a ultrafialov\u00e9ho z\u00e1\u0159en\u00ed poch\u00e1z\u00ed ze Slunce. Vysoce energetick\u00e9 rentgenov\u00e9 z\u00e1\u0159en\u00ed, gama z\u00e1\u0159en\u00ed a kosmick\u00e9 z\u00e1\u0159en\u00ed \u2013 \u010d\u00e1stice pohybuj\u00edc\u00ed se t\u00e9m\u011b\u0159 rychlost\u00ed sv\u011btla \u2013 p\u0159ich\u00e1zej\u00ed ze vzd\u00e1len\u00fdch hv\u011bzdn\u00fdch soustav.<\/p>","protected":false},"excerpt":{"rendered":"<p>In space, no one can hear you scream. This is because there is no air in space \u2013 it is a vacuum. Sound waves cannot travel through a vacuum. &#8216;Outer [&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\/2004\/12\/earth_from_space2\/17871152-2-eng-GB\/Earth_from_space.jpg","esa_banner_description":"","esa_banner_credit":"ESA","esa_banner_licence":"ESA Standard Licence","esa_banner_detail_url":"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2004\/12\/Earth_from_space2","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":[10,11,19],"tags":[2],"panel":[],"language":[],"age":[],"duration":[],"resource_type":[],"audience":[],"wf_post_folders":[],"class_list":["post-1005","post","type-post","status-publish","format-standard","hentry","category-learn","category-our-universe","category-story-of-the-universe","tag-background-article"],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/kids.esa.int\/cs\/wp-json\/wp\/v2\/posts\/1005","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=1005"}],"version-history":[{"count":1,"href":"https:\/\/kids.esa.int\/cs\/wp-json\/wp\/v2\/posts\/1005\/revisions"}],"predecessor-version":[{"id":2148,"href":"https:\/\/kids.esa.int\/cs\/wp-json\/wp\/v2\/posts\/1005\/revisions\/2148"}],"wp:attachment":[{"href":"https:\/\/kids.esa.int\/cs\/wp-json\/wp\/v2\/media?parent=1005"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/kids.esa.int\/cs\/wp-json\/wp\/v2\/categories?post=1005"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/kids.esa.int\/cs\/wp-json\/wp\/v2\/tags?post=1005"},{"taxonomy":"panel","embeddable":true,"href":"https:\/\/kids.esa.int\/cs\/wp-json\/wp\/v2\/panel?post=1005"},{"taxonomy":"language","embeddable":true,"href":"https:\/\/kids.esa.int\/cs\/wp-json\/wp\/v2\/language?post=1005"},{"taxonomy":"age","embeddable":true,"href":"https:\/\/kids.esa.int\/cs\/wp-json\/wp\/v2\/age?post=1005"},{"taxonomy":"duration","embeddable":true,"href":"https:\/\/kids.esa.int\/cs\/wp-json\/wp\/v2\/duration?post=1005"},{"taxonomy":"resource_type","embeddable":true,"href":"https:\/\/kids.esa.int\/cs\/wp-json\/wp\/v2\/resource_type?post=1005"},{"taxonomy":"audience","embeddable":true,"href":"https:\/\/kids.esa.int\/cs\/wp-json\/wp\/v2\/audience?post=1005"},{"taxonomy":"wf_post_folders","embeddable":true,"href":"https:\/\/kids.esa.int\/cs\/wp-json\/wp\/v2\/wf_post_folders?post=1005"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}