{"id":970,"date":"2005-07-11T09:32:00","date_gmt":"2005-07-11T07:32:00","guid":{"rendered":"https:\/\/kids.esa.int\/history_s_greatest_comet_hunter\/"},"modified":"2026-10-08T00:34:21","modified_gmt":"2026-10-07T22:34:21","slug":"history_s_greatest_comet_hunter","status":"publish","type":"post","link":"https:\/\/kids.esa.int\/fi\/history_s_greatest_comet_hunter\/","title":{"rendered":"Historian suurin komeettamets\u00e4st\u00e4j\u00e4"},"content":{"rendered":"<div class=\"lede\">\n<p>Ajoittain paljaalla silm\u00e4ll\u00e4kin n\u00e4kyy kirkas komeetta, jolla on pitk\u00e4t, per\u00e4ss\u00e4 roikkuvat h\u00e4nn\u00e4t. Viime vuosina ESA:n ja NASA:n SOHO-avaruusluotain on kuitenkin osoittanut, ett\u00e4 n\u00e4m\u00e4 \u201clikaiset lumipallot\u201d ovat paljon yleisempi\u00e4 kuin kukaan olisi voinut kuvitella.<\/p>\n<\/div>\n<p>SOHO on suunniteltu tarkkailemaan Aurinkoa, ei etsim\u00e4\u00e4n komeettoja. Yksi sen instrumenteista, nimelt\u00e4\u00e4n LASCO, on tarkoitettu Auringon ulomman ilmakeh\u00e4n (koronan) havainnointiin. Sen ansiosta SOHOsta on kuitenkin tullut historian suurin komeettojen etsij\u00e4.<\/p>\n<p>LASCO tutkii himme\u00e4\u00e4 koronaa suodattamalla pois Auringon kirkkaan valon. Sattumalta t\u00e4m\u00e4 mahdollistaa my\u00f6s pienten, Aurinkoa hipovien komeettojen havaitsemisen. Suurin osa n\u00e4ist\u00e4 j\u00e4isist\u00e4 tulokkaista ohittaa Auringon pinnan alle 800 000 km:n et\u00e4isyydelt\u00e4 \u2013 niin l\u00e4helt\u00e4, ett\u00e4 ne h\u00f6yrystyv\u00e4t tai sy\u00f6ksyv\u00e4t sen tuliseen uuniin.<\/p>\n<figure class=\"wp-block-image size-large\" data-width=\"3055\" data-credit=\"ESA\" data-detail-url=\"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2000\/09\/SOHO_spacecraft2\" data-licence=\"ESA Standard Licence\" data-licence-url=\"https:\/\/www.esa.int\/ESA_Multimedia\/Terms_and_conditions_of_use_of_images_and_videos_available_on_the_esa_website\"><img decoding=\"async\" loading=\"lazy\" style=\"max-width:100%;height:auto\" src=\"https:\/\/www.esa.int\/var\/esa\/storage\/images\/esa_multimedia\/images\/2000\/09\/soho_spacecraft2\/17865750-3-eng-GB\/SOHO_spacecraft.jpg\" alt=\"SOHO spacecraft\"><figcaption>SOHO-avaruusluotain<\/figcaption><\/figure>\n<p>Ennen SOHO:n laukaisua joulukuussa 1995 avaruusluotaimet olivat l\u00f6yt\u00e4neet vain 16 aurinkoa hipovaa komeettaa. 6. hein\u00e4kuuta 2005 menness\u00e4 pelk\u00e4st\u00e4\u00e4n SOHO oli l\u00f6yt\u00e4nyt per\u00e4ti 990 komeettaa. T\u00e4m\u00e4 tarkoittaa, ett\u00e4 SOHO on l\u00f6yt\u00e4nyt l\u00e4hes puolet kaikista komeetoista, joiden kiertoradat on laskettu historian alusta l\u00e4htien. T\u00e4m\u00e4n huikean kokonaism\u00e4\u00e4r\u00e4n odotetaan ylitt\u00e4v\u00e4n 1 000 t\u00e4m\u00e4n kes\u00e4n aikana ja kasvavan edelleen.<\/p>\n<p>Monet n\u00e4ist\u00e4 l\u00f6yd\u00f6ist\u00e4 ovat amat\u00f6\u00f6rien tekemi\u00e4, ja ne perustuvat internetist\u00e4 l\u00f6ytyviin SOHO-kuviin. SOHO-komeettien etsij\u00f6it\u00e4 on monista maista, muun muassa Yhdysvalloista, Yhdistyneest\u00e4 kuningaskunnasta, Kiinasta, Japanista, Taiwanista, Ven\u00e4j\u00e4lt\u00e4, Ukrainasta, Ranskasta, Saksasta ja Liettuasta.<\/p>\n<p>Komeetat ovat j\u00e4\u00e4- ja p\u00f6lypalasia \u2013 \u2018j\u00e4\u00e4mi\u00e4\u2019 planeettojen muodostumisesta 4,5 miljardia vuotta sitten.<\/p>\n<nav class=\"related\" aria-label=\"Aiheeseen liittyv\u00e4t\">\n<h2 class=\"related__heading\">Aiheeseen liittyv\u00e4t<\/h2>\n<div class=\"grid related__grid\">\n<div class=\"grid-item\">\n<article class=\"card focuson agency\"><a class=\"card__link\" href=\"\/fi\/build_a_soho_spacecraft\/\"><\/p>\n<figure class=\"thumbnail\"><img decoding=\"async\" class=\"image-bg\" src=\"https:\/\/www.esa.int\/var\/esa\/storage\/images\/esa_multimedia\/images\/2003\/11\/artist_s_impression_of_soho_spacecraft2\/17874814-2-eng-GB\/Artist_s_impression_of_SOHO_spacecraft.jpg\" alt=\"Test your skills - build your own SOHO spacecraft\" loading=\"lazy\"><span class=\"dimmer\"><\/span><\/figure>\n<header class=\"entry\">\n<h3 class=\"heading\">Kokeile taitojasi \u2013 rakenna oma SOHO-avaruusalus<\/h3>\n<\/header>\n<p><\/a><\/article>\n<\/div>\n<\/div>\n<\/nav>","protected":false},"excerpt":{"rendered":"<p>From time to time a bright comet with long, trailing tails becomes visible with the naked eye. However, in recent years the ESA \/ NASA SOHO spacecraft has shown that [&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\/2003\/09\/soho_see_two_comets_plunging_into_the_sun2\/17885766-2-eng-GB\/SOHO_see_two_comets_plunging_into_the_Sun.gif","esa_banner_description":"SOHO see two comets plunging into the Sun","esa_banner_credit":"SOHO\/LASCO (ESA\/NASA)","esa_banner_licence":"ESA Standard Licence","esa_banner_detail_url":"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2003\/09\/SOHO_see_two_comets_plunging_into_the_Sun2","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":[],"panel":[],"language":[],"age":[],"duration":[],"resource_type":[],"audience":[],"wf_post_folders":[],"class_list":["post-970","post","type-post","status-publish","format-standard","hentry","category-comets-and-meteors","category-learn","category-our-universe"],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/posts\/970","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=970"}],"version-history":[{"count":4,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/posts\/970\/revisions"}],"predecessor-version":[{"id":4763,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/posts\/970\/revisions\/4763"}],"wp:attachment":[{"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/media?parent=970"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/categories?post=970"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/tags?post=970"},{"taxonomy":"panel","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/panel?post=970"},{"taxonomy":"language","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/language?post=970"},{"taxonomy":"age","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/age?post=970"},{"taxonomy":"duration","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/duration?post=970"},{"taxonomy":"resource_type","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/resource_type?post=970"},{"taxonomy":"audience","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/audience?post=970"},{"taxonomy":"wf_post_folders","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/wf_post_folders?post=970"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}