{"id":38614,"date":"2026-10-24T15:29:43","date_gmt":"2026-10-24T15:29:43","guid":{"rendered":"https:\/\/www.worldclock.com\/sterrentijd-berekenen\/"},"modified":"2026-10-24T15:29:43","modified_gmt":"2026-10-24T15:29:43","slug":"sterrentijd-berekenen","status":"publish","type":"page","link":"https:\/\/www.worldclock.com\/nl\/sterrentijd-berekenen\/","title":{"rendered":"Sterrentijd &#038; Juliaanse datum berekenen"},"content":{"rendered":"<div class=\"wc wc-tool-page wc-tool-page--sidereal\"><header class=\"wc-thero\"><div class=\"wc-thero__text\"><nav class=\"wc-crumbs\" aria-label=\"Breadcrumb\"><ol><li><a href=\"https:\/\/www.worldclock.com\/nl\/\">Wereldklok<\/a><\/li><li><a href=\"https:\/\/www.worldclock.com\/nl\/tools\/\">Tijdtools<\/a><\/li><li><span aria-current=\"page\">Sterrentijd &amp; Juliaanse datum berekenen<\/span><\/li><\/ol><\/nav><p class=\"wc-eyebrow\"><span aria-hidden=\"true\">\ud83c\udf0c<\/span> Gratis tool<\/p><h1 class=\"wc-thero__title\">Sterrentijd &amp; Juliaanse datum berekenen<\/h1><p class=\"wc-thero__lead\">Live lokale sterrentijd, Greenwich-sterrentijd, Juliaanse datum en gemodificeerde Juliaanse datum voor elke plaats en elk tijdstip.<\/p><\/div><\/header><div class=\"wc-tool\"><div class=\"wc-sid\" data-wc-tool=\"sidereal\" data-default=\"{&quot;n&quot;:&quot;Greenwich&quot;,&quot;t&quot;:&quot;Europe\\\/London&quot;,&quot;f&quot;:&quot;gb&quot;,&quot;a&quot;:51.4769,&quot;o&quot;:-0.0005}\"><div class=\"wc-tbar\"><div class=\"wc-field wc-field--grow\"><span>Locatie<\/span><div class=\"wc-search wc-search--tool\" data-wc-search data-mode=\"add\"><input type=\"search\" placeholder=\"Zoek een stad\u2026\" aria-label=\"Zoek een stad\u2026\" autocomplete=\"off\"><ul class=\"wc-search__results\" hidden><\/ul><\/div><\/div><label class=\"wc-field\"><span>Lengtegraad \u00b0<\/span><input type=\"number\" step=\"0.0001\" min=\"-180\" max=\"180\" data-lng><\/label><button type=\"button\" class=\"wc-btn wc-btn--ghost\" data-geo>\ud83d\udccd Gebruik mijn locatie<\/button><\/div><div class=\"wc-sunc__place\" data-place><\/div><div class=\"wc-sunc__cards\" data-cards><\/div><div class=\"wc-panel\" style=\"margin-top:16px\"><h2>Een datum omrekenen<\/h2><label class=\"wc-field\"><span>Datum &amp; tijd (UTC)<\/span><input type=\"datetime-local\" step=\"1\" data-dt><\/label><dl class=\"wc-unix__out\" data-out><\/dl><\/div><\/div><\/div><section class=\"wc-section wc-tool-info\"><div class=\"wc-prose\"><h2>Wat is sterrentijd?<\/h2><p>Sterrentijd meet de draaiing van de aarde ten opzichte van de verre sterren in plaats van de zon. Een sterrendag duurt ongeveer <strong>23 uur, 56 minuten en 4 seconden<\/strong> \u2013 bijna vier minuten korter dan een zonnedag \u2013 dus de sterren komen elke nacht vier minuten eerder op. Sterrenkundigen gebruiken de <strong>lokale sterrentijd (LST)<\/strong> om telescopen te richten: een ster staat het hoogst aan de hemel als de LST gelijk is aan haar rechte klimming.<\/p><p>De <strong>Juliaanse datum<\/strong> is een doorlopende telling van dagen sinds 12:00 UTC op 1 januari 4713 v.Chr., die in de sterrenkunde wordt gebruikt om kalenderproblemen te vermijden. De <strong>gemodificeerde Juliaanse datum<\/strong> (MJD) is JD \u2212 2.400.000,5 en begint om middernacht.<\/p><\/div><\/section><section class=\"wc-section wc-faq\"><h2>Veelgestelde vragen<\/h2><details><summary>Hoe bereken ik de lokale sterrentijd?<\/summary><p>Bereken de Greenwich Mean Sidereal Time uit de Juliaanse datum en tel daar je lengtegraad in uren bij op (lengtegraad \u00f7 15, oost positief). De rekenhulp hierboven doet dit live voor elke locatie.<\/p><\/details><\/section><section class=\"wc-section wc-tools-grid\"><div class=\"wc-section__head\"><h2>Meer gratis tijdtools<\/h2><a href=\"https:\/\/www.worldclock.com\/nl\/tools\/\">Alle tools \u2192<\/a><\/div><div class=\"wc-toolcards\"><a class=\"wc-toolcard wc-toolcard--sun\" href=\"https:\/\/www.worldclock.com\/nl\/zonsopkomst-zonsondergang\/\"><span class=\"wc-toolcard__icon\" aria-hidden=\"true\">\ud83c\udf05<\/span><span class=\"wc-toolcard__name\">Zonsopkomst &amp; zonsondergang<\/span><span class=\"wc-toolcard__desc\">Zonsopkomst, zonsondergang en gouden uur.<\/span><\/a><a class=\"wc-toolcard wc-toolcard--golden\" href=\"https:\/\/www.worldclock.com\/nl\/gouden-uur-berekenen\/\"><span class=\"wc-toolcard__icon\" aria-hidden=\"true\">\ud83d\udcf8<\/span><span class=\"wc-toolcard__name\">Gouden uur berekenen<\/span><span class=\"wc-toolcard__desc\">Beste licht voor foto\u2019s.<\/span><\/a><a class=\"wc-toolcard wc-toolcard--moon\" href=\"https:\/\/www.worldclock.com\/nl\/maanfase\/\"><span class=\"wc-toolcard__icon\" aria-hidden=\"true\">\ud83c\udf15<\/span><span class=\"wc-toolcard__name\">Maanfase vandaag<\/span><span class=\"wc-toolcard__desc\">De maan van vanavond &amp; maankalender.<\/span><\/a><a class=\"wc-toolcard wc-toolcard--fullmoon\" href=\"https:\/\/www.worldclock.com\/nl\/volle-maan-kalender\/\"><span class=\"wc-toolcard__icon\" aria-hidden=\"true\">\ud83c\udf1d<\/span><span class=\"wc-toolcard__name\">Volle-maankalender<\/span><span class=\"wc-toolcard__desc\">Data &amp; namen van volle manen.<\/span><\/a><a class=\"wc-toolcard wc-toolcard--moonrise\" href=\"https:\/\/www.worldclock.com\/nl\/maanopkomst-maanondergang\/\"><span class=\"wc-toolcard__icon\" aria-hidden=\"true\">\ud83c\udf19<\/span><span class=\"wc-toolcard__name\">Tijden van maanopkomst &amp; maanondergang<\/span><span class=\"wc-toolcard__desc\">Wanneer de maan opkomt &amp; ondergaat.<\/span><\/a><a class=\"wc-toolcard wc-toolcard--birthmoon\" href=\"https:\/\/www.worldclock.com\/nl\/maanfase-verjaardag\/\"><span class=\"wc-toolcard__icon\" aria-hidden=\"true\">\ud83c\udf82<\/span><span class=\"wc-toolcard__name\">De maan op je verjaardag<\/span><span class=\"wc-toolcard__desc\">De maan op elke datum.<\/span><\/a><a class=\"wc-toolcard wc-toolcard--astro\" href=\"https:\/\/www.worldclock.com\/nl\/astronomische-kalender\/\"><span class=\"wc-toolcard__icon\" aria-hidden=\"true\">\ud83d\udd2d<\/span><span class=\"wc-toolcard__name\">Sterrenkundekalender<\/span><span class=\"wc-toolcard__desc\">Verduisteringen, meteoren &amp; hemelverschijnselen.<\/span><\/a><a class=\"wc-toolcard wc-toolcard--converter\" href=\"https:\/\/www.worldclock.com\/nl\/tijdzone-omrekenen\/\"><span class=\"wc-toolcard__icon\" aria-hidden=\"true\">\ud83d\udd01<\/span><span class=\"wc-toolcard__name\">Tijdzone omrekenen<\/span><span class=\"wc-toolcard__desc\">Reken een tijd om tussen willekeurige steden.<\/span><\/a><\/div><\/section><\/div>\n","protected":false},"excerpt":{"rendered":"","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_acf_changed":false,"_kad_blocks_custom_css":"","_kad_blocks_head_custom_js":"","_kad_blocks_body_custom_js":"","_kad_blocks_footer_custom_js":"","_kad_post_transparent":"","_kad_post_title":"","_kad_post_layout":"","_kad_post_sidebar_id":"","_kad_post_content_style":"","_kad_post_vertical_padding":"","_kad_post_feature":"","_kad_post_feature_position":"","_kad_post_header":false,"_kad_post_footer":false,"_kad_post_classname":"","footnotes":"","bs_cache_bypass_cache":0,"bs_cache_related_page":0},"class_list":["post-38614","page","type-page","status-publish","hentry"],"acf":[],"taxonomy_info":[],"featured_image_src_large":false,"author_info":{"display_name":"clocker","author_link":"https:\/\/www.worldclock.com\/nl\/author\/clocker\/"},"comment_info":"","_links":{"self":[{"href":"https:\/\/www.worldclock.com\/nl\/wp-json\/wp\/v2\/pages\/38614","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.worldclock.com\/nl\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.worldclock.com\/nl\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.worldclock.com\/nl\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.worldclock.com\/nl\/wp-json\/wp\/v2\/comments?post=38614"}],"version-history":[{"count":0,"href":"https:\/\/www.worldclock.com\/nl\/wp-json\/wp\/v2\/pages\/38614\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.worldclock.com\/nl\/wp-json\/wp\/v2\/media?parent=38614"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}