{"id":694,"date":"2012-11-30T14:15:00","date_gmt":"2012-11-30T13:15:00","guid":{"rendered":"https:\/\/kids.esa.int\/europe_s_comet_explorers\/"},"modified":"2026-10-08T00:31:13","modified_gmt":"2026-10-07T22:31:13","slug":"europe_s_comet_explorers","status":"publish","type":"post","link":"https:\/\/kids.esa.int\/fi\/europe_s_comet_explorers\/","title":{"rendered":"Euroopan komeettatutkijat"},"content":{"rendered":"
\n

13. maaliskuuta 1986 ESAn Giotto-avaruusluotain l\u00e4hetti kuvia mustasta, perunanmuotoisesta kohteesta, josta suihkusi avaruuteen kirkkaita ainevirtoja. Se oli ensimm\u00e4inen kerta, kun kukaan oli n\u00e4hnyt komeetan ytimess\u00e4 olevan kiinte\u00e4n ytimen.<\/p>\n<\/div>\n

Giotton kohteena oli Halley-komeetta, joka on nimetty 1600-luvun brittil\u00e4isen t\u00e4htitieteilij\u00e4n Edmond Halleyn mukaan. H\u00e4n oli ensimm\u00e4inen, joka tajusi, ett\u00e4 t\u00e4m\u00e4 kirkas komeetta vierailee s\u00e4\u00e4nn\u00f6llisesti ja palaa aurinkokunnan sis\u00e4osiin 75\u201376 vuoden v\u00e4lein. Sen seuraava vierailu taivaallamme on suunniteltu vuodelle 2061.<\/p>\n

Halleyn komeetta on tunnetuin niist\u00e4 miljoonista komeetoista, jotka kiert\u00e4v\u00e4t Aurinkoa. Vaikka Halleyn komeetta olisi aurinkokunnan ulko-osien pimeydess\u00e4, se vaikuttaa silti planeettaamme. Joka lokakuu Maa kulkee komeetan j\u00e4tt\u00e4m\u00e4n hienon p\u00f6lyvirran l\u00e4pi, mik\u00e4 aiheuttaa Orionidien meteorimyrskyn. Halleyn komeetan uskotaan olevan vastuussa my\u00f6s Eta-Aquaridien meteoriparvesta, joka esiintyy joka vuosi toukokuussa. N\u00e4m\u00e4 meteorit, joita usein kutsutaan \u201ct\u00e4hdenlennoksi\u201d, ovat kirkkaita j\u00e4lki\u00e4, joita j\u00e4tt\u00e4v\u00e4t pienet, nopeasti liikkuvat komeetan j\u00e4\u00e4nteet, jotka palavat loppuun Maan ilmakeh\u00e4ss\u00e4.<\/p>\n

\"Rosetta
Rosetta kiert\u00e4\u00e4 komeetta 67P\/Churyumov-Gerasimenkoa<\/figcaption><\/figure>\n

Giotton merkitt\u00e4v\u00e4n menestyksen j\u00e4lkeen avaruusluotaimilla on tutkittu my\u00f6s muita komeettoja. Kunnianhimoisin hanke on kuitenkin ESA:n Rosetta-luotain, joka l\u00e4htee komeetan per\u00e4\u00e4n ja saapuu Churyumov-Gerasimenko-komeetan luo vuonna 2014. Rosetta lent\u00e4\u00e4 komeetan ytimen vierell\u00e4 ja tutkii perusteellisesti muutoksia, joita tapahtuu, kun aurinko l\u00e4mmitt\u00e4\u00e4 sit\u00e4. Se my\u00f6s laukaisee Philae-nimisen pienen luotaimen, joka suorittaa ensimm\u00e4isen pehme\u00e4n laskeutumisen komeetalle!<\/p>","protected":false},"excerpt":{"rendered":"

On 13 March 1986, ESA\u2019s Giotto spacecraft sent back pictures of a black, potato-shaped object that was blasting bright jets of material into space. It was the first time that […]<\/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\/11\/comet_halley_close_up3\/17877183-2-eng-GB\/Comet_Halley_close_up.jpg","esa_banner_description":"Comet Halley close up","esa_banner_credit":"ESA\/MPS","esa_banner_licence":"ESA Standard Licence","esa_banner_detail_url":"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2012\/11\/Comet_Halley_close_up3","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-694","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\/694","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=694"}],"version-history":[{"count":4,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/posts\/694\/revisions"}],"predecessor-version":[{"id":4631,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/posts\/694\/revisions\/4631"}],"wp:attachment":[{"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/media?parent=694"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/categories?post=694"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/tags?post=694"},{"taxonomy":"panel","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/panel?post=694"},{"taxonomy":"language","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/language?post=694"},{"taxonomy":"age","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/age?post=694"},{"taxonomy":"duration","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/duration?post=694"},{"taxonomy":"resource_type","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/resource_type?post=694"},{"taxonomy":"audience","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/audience?post=694"},{"taxonomy":"wf_post_folders","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/wf_post_folders?post=694"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}