{"id":10461,"date":"2023-12-26T20:29:21","date_gmt":"2023-12-26T20:29:21","guid":{"rendered":"https:\/\/groupeastronomiespa.be\/astrogas\/ic-342\/"},"modified":"2025-06-08T22:43:55","modified_gmt":"2025-06-08T20:43:55","slug":"ic-342","status":"publish","type":"post","link":"https:\/\/groupeastronomiespa.be\/astrogas\/ic-342\/","title":{"rendered":"IC 342"},"content":{"rendered":"<p>Ayant pris avantage d&rsquo;un miraculeux ciel d\u00e9gag\u00e9 ce 17\/12\/23, j&rsquo;ai pu terminer mon projet sur IC 342.<br \/>\nC&rsquo;est une galaxie spirale interm\u00e9diaire vue de face et situ\u00e9e dans la constellation de la Girafe.<br \/>\nElle est situ\u00e9e pr\u00e8s du plan de notre galaxie et voit sa lumi\u00e8re absorb\u00e9e par une forte densit\u00e9 de gaz et de poussi\u00e8res qui si\u00e8gent le long du plan galactique.<br \/>\nBien qu&rsquo;elle soit constitu\u00e9e de grains dont la taille est inf\u00e9rieure \u00e0 0,1 micron et que sa concentration soit faible, la poussi\u00e8re galactique constitue un puissant filtre dont IC 342 fait les frais.<br \/>\nSans cette poussi\u00e8re, la galaxie de la Girafe serait l&rsquo;une des vedettes de nos nuits, alors qu&rsquo;en r\u00e9alit\u00e9 elle a une magnitude de 9, ce qui n\u00e9cessite l&#8217;emploi d&rsquo;un t\u00e9lescope de bon diam\u00e8tre pour la distinguer.<br \/>\nAjouter \u00e0 cela la myriade d&rsquo;\u00e9toiles de notre galaxie situ\u00e9e entre nous et IC342.<\/p>\n<p>\u00c9tant donn\u00e9 la proximit\u00e9 de IC 342, l&rsquo;\u00e9valuation de sa distance par la m\u00e9thode du d\u00e9calage vers le rouge donne des r\u00e9sultats incorrects.<br \/>\nDonc, il faut utiliser d&rsquo;autres m\u00e9thodes pour \u00e9valuer sa distance.<br \/>\nDe nombreuses mesures bas\u00e9es sur ces autres m\u00e9thodes donnent une distance de \u223c10,6 millions d&rsquo;Al.<br \/>\n\u00c9tant donn\u00e9 cette \u00ab\u00a0proximit\u00e9\u00a0\u00bb, on pourrait penser que cette galaxie est un membre du Groupe local, mais ce n&rsquo;est pas le cas.<br \/>\nEn fait, IC 342 ainsi que NGC 1560, NGC 1569, UGCA 92 et UGCA 105 sont des galaxies du groupe IC 342\/Maffei, un groupe voisin du Groupe local.<\/p>\n<p>La masse du trou noir supermassif au centre de la galaxie IC 342 serait comprise entre 1,4 et 5,4 millions de Masses solaire.<\/p>\n<p>Du coup, ce n&rsquo;est pas un objet facile \u00e0 traiter pour faire ressortir des d\u00e9tails&#8230;tout du moins dans mon cas.<br \/>\nVoici ma version <\/p>\n<p><a href=\"https:\/\/groupeastronomiespa.be\/astrogas\/wp-content\/uploads\/2025\/06\/48_20231226-IC342.jpg\" data-lbwps-width=\"3702\" data-lbwps-height=\"3370\" data-lbwps-srcsmall=\"https:\/\/groupeastronomiespa.be\/astrogas\/wp-content\/uploads\/2025\/06\/48_20231226-IC342-300x273.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"size-medium\" src=\"https:\/\/groupeastronomiespa.be\/astrogas\/wp-content\/uploads\/2025\/06\/48_20231226-IC342-300x273.jpg\" alt=\"\" width=\"300\" height=\"273\" \/><\/a><\/p>\n<p>Technique<br \/>\nL  20x180sec  &#8211;  19x240sec  &#8211;  10x300sec  =  60+76= 2.25 H<br \/>\nR  20x180sec  &#8211;  15x300sec                      =  60+75= 2.25 H<br \/>\nG  12x180sec  &#8211;  15x300sec                      = 36+75= 1.85 H<br \/>\nB  19x240sec  &#8211;  15x300sec                       = 76+75= 2.5 H<br \/>\nHa  19x300sec                                          = 95     = 1.6 H<\/p>\n<p>Total 10.45 H<\/p>\n<p>T\u00e9lescope Skywatcher 250\/1200 &#8211; Monture AZEQ6 &#8211; Cam\u00e9ra: ZWO 1600MM Pro &#8211; Guidage: ZWO 120 MM Mini + Lunette Artesky 70\/ 400 &#8211;<br \/>\nNINA &#8211; PHD2 &#8211; GSS &#8211; SharpCap pour Polar align. &#8211; Stellarium &#8211;<br \/>\nProcess: Pixinsight.<\/p>\n<p>Richard Hendrick<\/p>\n\n\n<div class=\"kk-star-ratings kksr-auto kksr-align-left kksr-valign-bottom\"\n    data-payload='{&quot;align&quot;:&quot;left&quot;,&quot;id&quot;:&quot;10461&quot;,&quot;slug&quot;:&quot;default&quot;,&quot;valign&quot;:&quot;bottom&quot;,&quot;ignore&quot;:&quot;&quot;,&quot;reference&quot;:&quot;auto&quot;,&quot;class&quot;:&quot;&quot;,&quot;count&quot;:&quot;0&quot;,&quot;legendonly&quot;:&quot;&quot;,&quot;readonly&quot;:&quot;&quot;,&quot;score&quot;:&quot;0&quot;,&quot;starsonly&quot;:&quot;&quot;,&quot;best&quot;:&quot;10&quot;,&quot;gap&quot;:&quot;5&quot;,&quot;greet&quot;:&quot;Veuillez voter&quot;,&quot;legend&quot;:&quot;0\\\/10 - (0 vote)&quot;,&quot;size&quot;:&quot;18&quot;,&quot;title&quot;:&quot;IC 342&quot;,&quot;width&quot;:&quot;0&quot;,&quot;_legend&quot;:&quot;{score}\\\/{best} - ({count} {votes})&quot;,&quot;font_factor&quot;:&quot;1.25&quot;}'>\n            \n<div class=\"kksr-stars\">\n    \n<div class=\"kksr-stars-inactive\">\n            <div class=\"kksr-star\" data-star=\"1\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 18px; height: 18px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" data-star=\"2\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 18px; height: 18px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" data-star=\"3\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 18px; height: 18px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" data-star=\"4\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 18px; height: 18px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" data-star=\"5\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 18px; height: 18px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" data-star=\"6\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 18px; height: 18px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" data-star=\"7\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 18px; height: 18px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" data-star=\"8\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 18px; height: 18px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" data-star=\"9\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 18px; height: 18px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" data-star=\"10\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 18px; height: 18px;\"><\/div>\n        <\/div>\n    <\/div>\n    \n<div class=\"kksr-stars-active\" style=\"width: 0px;\">\n            <div class=\"kksr-star\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 18px; height: 18px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 18px; height: 18px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 18px; height: 18px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 18px; height: 18px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 18px; height: 18px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 18px; height: 18px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 18px; height: 18px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 18px; height: 18px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 18px; height: 18px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 18px; height: 18px;\"><\/div>\n        <\/div>\n    <\/div>\n<\/div>\n                \n\n<div class=\"kksr-legend\" style=\"font-size: 14.4px;\">\n            <span class=\"kksr-muted\">Veuillez voter<\/span>\n    <\/div>\n    <\/div>\n","protected":false},"excerpt":{"rendered":"<p>Ayant pris avantage d&rsquo;un miraculeux ciel d\u00e9gag\u00e9 ce 17\/12\/23, j&rsquo;ai pu terminer mon projet sur IC 342. C&rsquo;est une galaxie spirale interm\u00e9diaire vue de face et situ\u00e9e dans la constellation de la Girafe. Elle est situ\u00e9e pr\u00e8s du plan de notre galaxie et voit sa lumi\u00e8re absorb\u00e9e par une forte densit\u00e9 de gaz et de [&hellip;]<\/p>\n","protected":false},"author":11,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_et_pb_use_builder":"","_et_pb_old_content":"","_et_gb_content_width":"","footnotes":""},"categories":[2],"tags":[],"class_list":["post-10461","post","type-post","status-publish","format-standard","hentry","category-astrophotos"],"_links":{"self":[{"href":"https:\/\/groupeastronomiespa.be\/astrogas\/wp-json\/wp\/v2\/posts\/10461","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/groupeastronomiespa.be\/astrogas\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/groupeastronomiespa.be\/astrogas\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/groupeastronomiespa.be\/astrogas\/wp-json\/wp\/v2\/users\/11"}],"replies":[{"embeddable":true,"href":"https:\/\/groupeastronomiespa.be\/astrogas\/wp-json\/wp\/v2\/comments?post=10461"}],"version-history":[{"count":1,"href":"https:\/\/groupeastronomiespa.be\/astrogas\/wp-json\/wp\/v2\/posts\/10461\/revisions"}],"predecessor-version":[{"id":11216,"href":"https:\/\/groupeastronomiespa.be\/astrogas\/wp-json\/wp\/v2\/posts\/10461\/revisions\/11216"}],"wp:attachment":[{"href":"https:\/\/groupeastronomiespa.be\/astrogas\/wp-json\/wp\/v2\/media?parent=10461"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/groupeastronomiespa.be\/astrogas\/wp-json\/wp\/v2\/categories?post=10461"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/groupeastronomiespa.be\/astrogas\/wp-json\/wp\/v2\/tags?post=10461"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}