{"id":728,"date":"2012-07-03T12:27:00","date_gmt":"2012-07-03T10:27:00","guid":{"rendered":"https:\/\/kids.esa.int\/titan_s_tides_point_to_a_hidden_ocean\/"},"modified":"2026-10-08T00:31:37","modified_gmt":"2026-10-07T22:31:37","slug":"titan_s_tides_point_to_a_hidden_ocean","status":"publish","type":"post","link":"https:\/\/kids.esa.int\/fi\/titan_s_tides_point_to_a_hidden_ocean\/","title":{"rendered":"Titanin vuorovedet viittaavat piilotettuun valtamereen"},"content":{"rendered":"
\n

Maata kutsutaan usein siniseksi planeetaksi, koska se on ainoa maailma aurinkokunnassamme, jonka pinta on suurelta osin veden peitossa. Useiden satelliittien, kuten Saturnuksen j\u00e4ttil\u00e4ism\u00e4isen kuun Titanin, pinnan alla uskotaan kuitenkin olevan valtameri\u00e4. Vihje Titanin pinnan alla olevan valtameren olemassaolosta on per\u00e4isin suurten vuoroveden vaihteluiden havainnoista.<\/p>\n<\/div>\n

Jokainen, joka vierailee rannikolla, tuntee vuorovedet \u2013 merenpinnan nousun ja laskun kahdesti p\u00e4iv\u00e4ss\u00e4. V\u00e4hemm\u00e4n ilmeisi\u00e4 ovat ne vuorovedet, jotka saavat maapallon kuoren nousemaan ja laskemaan muutamia kymmeni\u00e4 senttimetrej\u00e4. N\u00e4m\u00e4 vuorovedet johtuvat Kuun ja Auringon yhteisest\u00e4 painovoimavaikutuksesta Maahan. Titanin vuorovedet syntyv\u00e4t samalla tavalla. T\u00e4ll\u00e4 kertaa kuitenkin Saturnuksen vetovoima saa kuun muuttamaan muotoaan sen 16 p\u00e4iv\u00e4n kiertoradan aikana.<\/p>\n

Titanin muodonmuutos on havaittu seuraamalla tarkasti Cassini-avaruusluotaimen lentorataa, kun se lent\u00e4\u00e4 l\u00e4hell\u00e4 kuuta. Erot siin\u00e4, miten Titan veti Cassinia puoleensa, osoittivat, ett\u00e4 kuun painovoima \u2013 ja siten my\u00f6s sen muoto \u2013 oli muuttunut hyvin hieman. Kaukaisimmassa kohdassaan, kun Saturnuksen vetovoima on heikompi, Titan on l\u00e4hes pallomainen, kuten jalkapallo. Kun satelliitti on l\u00e4himp\u00e4n\u00e4 Saturnusta, se venyy niin, ett\u00e4 se muistuttaa enemm\u00e4n rugbypalloa.<\/p>\n

T\u00e4st\u00e4 johtuvat vuorovedet saavat Titanin pinnan nousemaan ja laskemaan yli 10 metri\u00e4. T\u00e4m\u00e4 vaihtelu on kuitenkin huomattavasti suurempi kuin mit\u00e4 voitaisiin odottaa, jos kuu olisi kauttaaltaan kiinte\u00e4\u00e4 ainetta. T\u00e4m\u00e4 viittaa siihen, ett\u00e4 sen noin 50 km paksun j\u00e4\u00e4kuoren alla on maanalainen meri, jonka syvyys on mahdollisesti 250 km.<\/p>","protected":false},"excerpt":{"rendered":"

Earth is often known as the blue planet, because it is the only world in our Solar System which is largely covered by water. However, a number of satellites, including […]<\/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\/2012\/06\/titan_s_tides_raised_by_saturn2\/17912925-2-eng-GB\/Titan_s_tides_raised_by_Saturn.jpeg","esa_banner_description":"","esa_banner_credit":"NASA\/JPL","esa_banner_licence":"ESA Standard Licence","esa_banner_detail_url":"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2012\/06\/Titan_s_tides_raised_by_Saturn2","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-728","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\/fi\/wp-json\/wp\/v2\/posts\/728","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/users\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/comments?post=728"}],"version-history":[{"count":1,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/posts\/728\/revisions"}],"predecessor-version":[{"id":1871,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/posts\/728\/revisions\/1871"}],"wp:attachment":[{"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/media?parent=728"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/categories?post=728"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/tags?post=728"},{"taxonomy":"panel","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/panel?post=728"},{"taxonomy":"language","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/language?post=728"},{"taxonomy":"age","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/age?post=728"},{"taxonomy":"duration","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/duration?post=728"},{"taxonomy":"resource_type","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/resource_type?post=728"},{"taxonomy":"audience","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/audience?post=728"},{"taxonomy":"wf_post_folders","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/wf_post_folders?post=728"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}