{"id":297,"date":"2019-04-04T12:15:36","date_gmt":"2019-04-04T10:15:36","guid":{"rendered":"https:\/\/kids.esa.int\/esa_test_a_new_pulsar_clock\/"},"modified":"2026-10-08T00:26:33","modified_gmt":"2026-10-07T22:26:33","slug":"esa_test_a_new_pulsar_clock","status":"publish","type":"post","link":"https:\/\/kids.esa.int\/sv\/esa_test_a_new_pulsar_clock\/","title":{"rendered":"ESA testar en ny pulsarklocka"},"content":{"rendered":"
\n

N\u00e4r var det senast du tittade p\u00e5 klockan? Kanske har du ett armbandsur eller en v\u00e4ggklocka. Har du n\u00e5gonsin funderat \u00f6ver hur exakt tiden den visar egentligen \u00e4r? I v\u00e5r vardag beh\u00f6ver klockor egentligen bara vara exakta inom n\u00e5gra minuter eller sekunder. Men vad h\u00e4nder om du \u00e4r forskare, ingenj\u00f6r eller astronaut? D\u00e5 kan du beh\u00f6va m\u00e4ta tiden mycket exakt. ESA:s forskare har b\u00f6rjat testa en ny typ av extremt exakt klocka som anv\u00e4nder pulsarer! Den kallas \u201cPulChron\u201d och m\u00e4ter tidens g\u00e5ng med hj\u00e4lp av radiopulser med millisekundfrekvens fr\u00e5n flera snabbt roterande neutronstj\u00e4rnor!<\/p>\n<\/div>\n

Neutronstj\u00e4rnor \u00e4r otroligt t\u00e4ta himlakroppar som bildas ur de kollapsade k\u00e4rnorna hos exploderande stj\u00e4rnor. De \u00e4r mycket sm\u00e5 j\u00e4mf\u00f6rt med vanliga stj\u00e4rnor och planeter \u2013 med en diameter p\u00e5 endast cirka 10 till 20 km \u2013 men de inneh\u00e5ller mer \u201cmateria\u201d, det vill s\u00e4ga massa, \u00e4n solen! Ibland roterar neutronstj\u00e4rnor mycket snabbt. D\u00e5 kallas de pulsarer, och det \u00e4r just dessa som forskarna i PulChron-projektet anv\u00e4nder sig av. N\u00e4r pulsarerna roterar avger de str\u00e5lar av radiov\u00e5gor som kan detekteras h\u00e4r p\u00e5 jorden. Effekten p\u00e5minner lite om hur vi ser de blinkande ljusen fr\u00e5n en fyr. Dessa radiopulsar \u00e4r s\u00e5 regelbundna att de skulle kunna utg\u00f6ra grunden f\u00f6r ett mycket exakt klocksystem \u2013 precis vad PulChron-teamet h\u00e5ller p\u00e5 att testa.\u00a0<\/p>\n

\"PulChron
Konfiguration av PulChron<\/figcaption><\/figure>\n

Vi har redan uppfunnit n\u00e5gra mycket bra metoder f\u00f6r att m\u00e4ta tiden. V\u00e5r b\u00e4sta metod hittills \u00e4r en apparat som kallas atomur. Elektroner i atomer kan ta upp eller avge mycket exakta m\u00e4ngder energi. Denna energi avges som en ljusv\u00e5g med en viss frekvens \u2013 ett visst antal hela v\u00e5gl\u00e4ngder per sekund \u2013 som kan anv\u00e4ndas f\u00f6r att m\u00e4ta tiden, precis som antalet hela sv\u00e4ngningar hos en pendel under en minut styr en golvklocka.<\/p>\n

Atomklockor kan vara b\u00e4ttre p\u00e5 korta tidsskalor, till exempel \u00e5r, men pulsarklockor som PulChron skulle kunna vara b\u00e4ttre \u00f6ver \u00e5rtionden, d\u00e5 enskilda atomklockor riskerar att sluta fungera. Detta inneb\u00e4r att pulsarklockor kan vara mycket anv\u00e4ndbara f\u00f6r framtida satellitnavigeringssystem, s\u00e5som ESA:s Galileo, som kr\u00e4ver oerh\u00f6rt exakt tidsm\u00e4tning under m\u00e5nga \u00e5r.<\/p>\n

\"Lovell
Lovell-teleskopet, Jodrell Bank<\/figcaption><\/figure>\n

Men vad h\u00e4nder om data fr\u00e5n en pulsar f\u00f6rvr\u00e4ngs \u2013 kanske av gravitationsv\u00e5gor, som \u00e4r som krusningar i rymden orsakade av kraftfulla kosmiska h\u00e4ndelser? Det skulle kunna f\u00e5 det att se ut som om pulsaren snurrar snabbare eller l\u00e5ngsammare under en kort stund. PulChron-teamet har t\u00e4nkt p\u00e5 detta och anv\u00e4nder d\u00e4rf\u00f6r fem stora radioteleskop runt om i Europa f\u00f6r att observera inte bara en, utan hela 18 pulsarer!\u00a0<\/p>\n

Kanske kommer pulsarklockor att bli vanligare i framtiden och, tillsammans med atomklockor, hj\u00e4lpa oss att m\u00e4ta tiden b\u00e4ttre \u00e4n n\u00e5gonsin tidigare!<\/p>\n

\"Galileo
Galileo-satelliten i omloppsbana<\/figcaption><\/figure>\n

Intressant fakta: Pulsarerna uppt\u00e4cktes 1967 av den brittiska astronomen Jocelyn Bell Burnell. Till en b\u00f6rjan trodde hon att de kunde vara bevis p\u00e5 att intelligenta utomjordiska varelser f\u00f6rs\u00f6kte kommunicera med oss!\u00a0<\/i><\/p>","protected":false},"excerpt":{"rendered":"

When was the last time you checked the time? Maybe you have a wristwatch, or a clock on the wall. Did you stop to think about how accurate the time […]<\/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\/2017\/05\/crab_on_lcd\/16946171-1-eng-GB\/Crab_on_LCD.jpg","esa_banner_description":"A pulsar is hidden deep within this supernova bubble. Copyright: NASA, ESA, G. Dubner (IAFE, CONICET-University of Buenos Aires) et al.; A. Loll et al.; T. Temim et al.; F. Seward et al.; VLA\/NRAO\/AUI\/NSF; Chandra\/CXC; Spitzer\/JPL-Caltech; XMM-Newton\/ESA; and Hubble\/STScI, CC BY 4.0","esa_banner_credit":"NASA, ESA, G. Dubner (IAFE, CONICET-University of Buenos Aires) et al.; A. Loll et al.; T. Temim et al.; F. Seward et al.; VLA\/NRAO\/AUI\/NSF; Chandra\/CXC; Spitzer\/JPL-Caltech; XMM-Newton\/ESA; and Hubble\/STScI,CC BY 4.0","esa_banner_licence":"CC BY 4.0 INT or ESA Standard Licence","esa_banner_detail_url":"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2017\/05\/Crab_on_LCD","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":[26],"tags":[],"panel":[],"language":[],"age":[],"duration":[],"resource_type":[],"audience":[],"wf_post_folders":[],"class_list":["post-297","post","type-post","status-publish","format-standard","hentry","category-news"],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/kids.esa.int\/sv\/wp-json\/wp\/v2\/posts\/297","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/kids.esa.int\/sv\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/kids.esa.int\/sv\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/kids.esa.int\/sv\/wp-json\/wp\/v2\/users\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/kids.esa.int\/sv\/wp-json\/wp\/v2\/comments?post=297"}],"version-history":[{"count":5,"href":"https:\/\/kids.esa.int\/sv\/wp-json\/wp\/v2\/posts\/297\/revisions"}],"predecessor-version":[{"id":4394,"href":"https:\/\/kids.esa.int\/sv\/wp-json\/wp\/v2\/posts\/297\/revisions\/4394"}],"wp:attachment":[{"href":"https:\/\/kids.esa.int\/sv\/wp-json\/wp\/v2\/media?parent=297"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/kids.esa.int\/sv\/wp-json\/wp\/v2\/categories?post=297"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/kids.esa.int\/sv\/wp-json\/wp\/v2\/tags?post=297"},{"taxonomy":"panel","embeddable":true,"href":"https:\/\/kids.esa.int\/sv\/wp-json\/wp\/v2\/panel?post=297"},{"taxonomy":"language","embeddable":true,"href":"https:\/\/kids.esa.int\/sv\/wp-json\/wp\/v2\/language?post=297"},{"taxonomy":"age","embeddable":true,"href":"https:\/\/kids.esa.int\/sv\/wp-json\/wp\/v2\/age?post=297"},{"taxonomy":"duration","embeddable":true,"href":"https:\/\/kids.esa.int\/sv\/wp-json\/wp\/v2\/duration?post=297"},{"taxonomy":"resource_type","embeddable":true,"href":"https:\/\/kids.esa.int\/sv\/wp-json\/wp\/v2\/resource_type?post=297"},{"taxonomy":"audience","embeddable":true,"href":"https:\/\/kids.esa.int\/sv\/wp-json\/wp\/v2\/audience?post=297"},{"taxonomy":"wf_post_folders","embeddable":true,"href":"https:\/\/kids.esa.int\/sv\/wp-json\/wp\/v2\/wf_post_folders?post=297"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}