{"id":9515,"date":"2017-12-29T18:53:09","date_gmt":"2017-12-29T17:53:09","guid":{"rendered":"http:\/\/projectes.xtec.cat\/zenit\/?p=9515"},"modified":"2023-07-03T07:55:43","modified_gmt":"2023-07-03T05:55:43","slug":"orbites","status":"publish","type":"post","link":"https:\/\/projectes.xtec.cat\/zenit\/general\/orbites\/","title":{"rendered":"1.2. \u00d2rbites dels sat\u00e8l\u00b7lits"},"content":{"rendered":"<div>\n<ul class=\"nav nav-tabs nav-pills\">\n<li class=\"nav-item\"><a class=\"nav-link active\" href=\"#consulta\" data-toggle=\"tab\">Consulta<\/a><\/li>\n<li class=\"nav-item\"><a class=\"nav-link\" href=\"#practica\" data-toggle=\"tab\">Practica<\/a><\/li>\n<\/ul>\n<div class=\"tab-content\" style=\"margin-top: 20px;\">\n<div id=\"consulta\" class=\"tab-pane active\">\n<p>Els sat\u00e8l\u00b7lits que orbiten entorn de la Terra ho fan en \u00f2rbites el\u00edptiques (circulars en la majoria de casos). El tipus d&#8217;\u00f2rbita es tria en funci\u00f3 de l&#8217;\u00fas assignat al sat\u00e8l\u00b7lit: posicionament, meteorologia &#8230;<br \/>\nEls sat\u00e8l\u00b7lits que es mouen en \u00f2rbites polars poden passar per sobre de qualsevol punt de la Terra a intervals de temps relativament curts, per la qual cosa poden obtenir dades a nivell mundial. Per contra, quan hi ha una inclinaci\u00f3 respecte l&#8217;\u00f2rbita polar, la zona explorada queda restringida a un marge redu\u00eft de latituds.<br \/>\nEn la imatge a escala que hi ha a sota es poden observar diferents tipus d&#8217;\u00f2rbites segons la seva dist\u00e0ncia a la Terra :<\/p>\n<ul>\n<li>En color <strong><span style=\"color: #00ffff;\">cyan<\/span><\/strong>, les \u00f2rbites baixes fins a 2.000 km d&#8217;altura (<em>Low Earth Orbit<\/em>, LEO). La circumfer\u00e8ncia en punts <strong><span style=\"color: #ff0000;\">vermells<\/span><\/strong> correspon a l&#8217;\u00f2rbita de l&#8217;estaci\u00f3 espacial internacional ISS (a 370 km d&#8217;altura).<\/li>\n<li>En color <strong><span style=\"color: #ffff00;\">groc<\/span><\/strong>, les \u00f2rbites mitjanes fins a 34.780 km d&#8217;altura (<em>Medium Earth<\/em> <em>Orbit<\/em>, MEO). La circumfer\u00e8ncia en tra\u00e7os <strong><span style=\"color: #00ff00;\">verds<\/span><\/strong> correspon a sistemes de posicionament GPS (a 20.230 km d&#8217;altura, amb un temps orbital de 12 hores).<\/li>\n<li>La circumfer\u00e8ncia en tra\u00e7os <strong>negres<\/strong> correspon a una \u00f2rbita geos\u00edncrona, a 35.786 km d&#8217;altura. Si el pla de l&#8217;orbita es troba en el pla de l&#8217;equador, tenim una \u00f2rbita geoestacion\u00e0ria (<em>Geostationary Orbit, <\/em>GEO). En aquest cas la posici\u00f3 del sat\u00e8l\u00b7lit respecte a la superf\u00edcie terrestre no varia i es pot observar un semiglobus terrestre sencer.<a title=\"By Image of earth: Gringer. Scale orbits: Mike1024 [Public domain], via Wikimedia Commons\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File%3AOrbits_around_earth_scale_diagram.svg\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter\" src=\"https:\/\/upload.wikimedia.org\/wikipedia\/commons\/thumb\/8\/8d\/Orbits_around_earth_scale_diagram.svg\/256px-Orbits_around_earth_scale_diagram.svg.png\" alt=\"Orbits around earth scale diagram\" width=\"411\" height=\"411\" \/><\/a><\/li>\n<\/ul>\n<p style=\"text-align: center;\"><a title=\"By Rrakanishu [GFDL (http:\/\/www.gnu.org\/copyleft\/fdl.html) or CC BY-SA 4.0 (https:\/\/creativecommons.org\/licenses\/by-sa\/4.0)], from Wikimedia Commons\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Orbitalaltitudes.jpg\"><img decoding=\"async\" class=\"aligncenter\" src=\"https:\/\/upload.wikimedia.org\/wikipedia\/commons\/thumb\/8\/82\/Orbitalaltitudes.jpg\/1024px-Orbitalaltitudes.jpg\" alt=\"Orbitalaltitudes\" \/><\/a>Dist\u00e0ncia a la Terra de les \u00f2rbites de sat\u00e8l\u00b7lits artificials, en comparaci\u00f3 amb l&#8217;\u00f2rbita lunar.<\/p>\n<\/div>\n<div id=\"practica\" class=\"tab-pane fade\">\n<p>En el simulador del moviment d&#8217;un sat\u00e8l\u00b7lit que hi ha a continuaci\u00f3, pots observar per quins punts sobre la superf\u00edcie terrestre passa un sat\u00e8l\u00b7lit. Desplega\u00a0 els controls i ajusta primer els par\u00e0metres de simulaci\u00f3 :<\/p>\n<ul>\n<li>Inclinaci\u00f3 de l&#8217;\u00f2rbita respecte l&#8217;equador (graus)<\/li>\n<li>Longitud del node ascendent (graus)<\/li>\n<li>Radi del peri\u00e0pside (quil\u00f2metres)<\/li>\n<li>Excentricitat<\/li>\n<\/ul>\n<p><a href=\"https:\/\/edumet.cat\/areatac\/zenit\/satelit.html\" target=\"_blank\" rel=\"noopener noreferrer\"><input type=\"button\" value=\"Veure en pantalla completa\" \/><\/a><\/p>\n<p><iframe loading=\"lazy\" style=\"border: 0px;\" title=\"\" src=\"https:\/\/edumet.cat\/areatac\/zenit\/satelit.html\" width=\"1024px\" height=\"500px\" scrolling=\"no\"> <\/iframe><\/p>\n<p>Et proposem una s\u00e8rie de preguntes que podr\u00e0s respondre usant el simulador. Els dos par\u00e0metres que has d&#8217;ajustar en cada simulaci\u00f3 s\u00f3n la inclinaci\u00f3 de l&#8217;\u00f2rbita i el per\u00edode de rotaci\u00f3 del sat\u00e8l\u00b7lit (pots ajustar el per\u00edode canviant el valor del radi del peri\u00e0pside).<\/p>\n<h3 style=\"text-align: center;\"><span style=\"color: #ff0000;\">Qu\u00e8 has apr\u00e8s sobre les \u00f2rbites ?<\/span><\/h3>\n<p><iframe loading=\"lazy\" src=\"https:\/\/projectes.xtec.cat\/zenit\/wp-admin\/admin-ajax.php?action=h5p_embed&amp;id=5\" width=\"1040\" height=\"348\" frameborder=\"0\" allowfullscreen=\"allowfullscreen\"><\/iframe><script src=\"http:\/\/projectes.xtec.cat\/zenit\/wp-content\/plugins\/h5p\/h5p-php-library\/js\/h5p-resizer.js\" charset=\"UTF-8\"><\/script><\/p>\n<\/div>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<ul class=\"nav nav-tabs nav-pills\">\n<li class=\"nav-item\"><a class=\"nav-link active\" href=\"#consulta\" data-toggle=\"tab\">Consulta<\/a><\/li>\n<li class=\"nav-item\"><a class=\"nav-link\" href=\"#practica\" data-toggle=\"tab\">Practica<\/a><\/li>\n<\/ul>\n<p>Els sat\u00e8l\u00b7lits que orbiten entorn de la Terra ho fan en \u00f2rbites el\u00edptiques (circulars en la majoria de casos). El tipus d&#8217;\u00f2rbita es tria en funci\u00f3 de l&#8217;\u00fas assignat al sat\u00e8l\u00b7lit: posicionament, meteorologia&hellip;  <a href=\"https:\/\/projectes.xtec.cat\/zenit\/general\/orbites\/\" title=\"Read 1.2. \u00d2rbites dels sat\u00e8l\u00b7lits\">Llegeix m\u00e9s\u00bb<\/a><\/p>\n","protected":false},"author":4,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_bbp_topic_count":0,"_bbp_reply_count":0,"_bbp_total_topic_count":0,"_bbp_total_reply_count":0,"_bbp_voice_count":0,"_bbp_anonymous_reply_count":0,"_bbp_topic_count_hidden":0,"_bbp_reply_count_hidden":0,"_bbp_forum_subforum_count":0,"footnotes":""},"categories":[1,330],"tags":[306,316],"class_list":["post-9515","post","type-post","status-publish","format-standard","hentry","category-general","category-obsterra","tag-plafo","tag-ud_posicionament"],"post_mailing_queue_ids":[],"_links":{"self":[{"href":"https:\/\/projectes.xtec.cat\/zenit\/wp-json\/wp\/v2\/posts\/9515","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/projectes.xtec.cat\/zenit\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/projectes.xtec.cat\/zenit\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/projectes.xtec.cat\/zenit\/wp-json\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/projectes.xtec.cat\/zenit\/wp-json\/wp\/v2\/comments?post=9515"}],"version-history":[{"count":4,"href":"https:\/\/projectes.xtec.cat\/zenit\/wp-json\/wp\/v2\/posts\/9515\/revisions"}],"predecessor-version":[{"id":11347,"href":"https:\/\/projectes.xtec.cat\/zenit\/wp-json\/wp\/v2\/posts\/9515\/revisions\/11347"}],"wp:attachment":[{"href":"https:\/\/projectes.xtec.cat\/zenit\/wp-json\/wp\/v2\/media?parent=9515"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/projectes.xtec.cat\/zenit\/wp-json\/wp\/v2\/categories?post=9515"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/projectes.xtec.cat\/zenit\/wp-json\/wp\/v2\/tags?post=9515"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}