{"id":551,"date":"2018-03-17T23:36:52","date_gmt":"2018-03-17T22:36:52","guid":{"rendered":"http:\/\/astroriom.net\/wp1\/?p=551"},"modified":"2023-11-01T19:28:15","modified_gmt":"2023-11-01T18:28:15","slug":"les-etoiles-variables-doubles-multiples","status":"publish","type":"post","link":"http:\/\/astroriom.net\/v2\/?p=551","title":{"rendered":"Les \u00e9toiles variables, doubles, multiples&#8230;"},"content":{"rendered":"<p>\t\t\t\t<span style=\"font-size: large;\"><span style=\"color: #ff3366;\"><b>Les<\/b><\/span> <strong><span style=\"color: #ff3366;\">\u00e9toiles variables<\/span><\/strong> : sont des \u00e9toiles dont l&rsquo;\u00e9clat varie au cours du temps, il en existe de diff\u00e9rents types.<\/span><\/p>\n<p><strong><span style=\"font-size: large;\">Les variables pulsantes <\/span><\/strong><span style=\"font-size: large;\">: ce sont les variables les plus courantes ; ces \u00e9toiles pr\u00e9sentent<\/span> <span style=\"font-size: large;\">une variation p\u00e9riodique de leur volume, ce qui engendre une modification de leur luminosit\u00e9 .<\/span><\/p>\n<p><strong><span style=\"font-size: large;\">Les variables par rotations <\/span><\/strong><span style=\"font-size: large;\">: poss\u00e8dent \u00e0 leur surface des taches sombres ou claires. Ainsi, en tournant sur elle-m\u00eame, l&rsquo;\u00e9toile nous fait parvenir plus ou moins de lumi\u00e8re.<\/span><\/p>\n<p><strong><span style=\"font-size: large;\">Les variables \u00e0 \u00e9clipses <\/span><\/strong><span style=\"font-size: large;\">: la pr\u00e9sence d&rsquo;une autre \u00e9toile (ou d&rsquo;une plan\u00e8te) autour de l&rsquo;\u00e9toile principale fait que, vue sous un certain angle, une de ces deux \u00e9toiles (ou plan\u00e8te) peut, \u00e0 intervalles r\u00e9guliers, \u00e9clipser l&rsquo;autre, et ainsi nous adresser une moindre luminosit\u00e9.<\/span><\/p>\n<p><span style=\"color: #ff3366;\"><span style=\"font-size: large;\"><b>Les \u00e9toiles doubles<\/b><\/span><\/span><span style=\"font-size: large;\"> : sont des paires d&rsquo;\u00e9toiles qui apparaissent comme proches l&rsquo;une de l&rsquo;autre dans le ciel, lorsqu&rsquo;on les observe depuis la Terre.<\/span><\/p>\n<p><strong><span style=\"font-size: large;\">Les doubles optiques <\/span><\/strong><span style=\"font-size: large;\">: c&rsquo;est un alignement d\u00fb au hasard de deux \u00e9toiles, qui se trouvent dans le ciel \u00e0 des distances diff\u00e9rentes, mais qui sont vues sous le m\u00eame angle de vis\u00e9e depuis la Terre.<\/span><\/p>\n<p><strong><span style=\"font-size: large;\">Les syst\u00e8mes binaires <\/span><\/strong><span style=\"font-size: large;\">: les deux \u00e9toiles sont li\u00e9es par la gravitation, l&rsquo;une tournant autour de l&rsquo;autre ; l&rsquo;int\u00e9r\u00eat pour les astronomes de ces syst\u00e8mes binaires, est que la connaissance de leur mouvement permet de d\u00e9terminer la masse des \u00e9toiles qui les composent.<\/span><\/p>\n<p><span style=\"font-size: large;\">Ci-dessous une liste d&rsquo;\u00e9toiles doubles \u00e0 observer facilement :<\/span><\/p>\n<p><a href=\"http:\/\/www.astrosurf.com\/lecurieux\/Evenement%20ciel\/Liste%20des%20etoiles%20doubles.pdf\"><span style=\"font-size: large;\">http:\/\/www.astrosurf.com\/lecurieux\/Evenement%20ciel\/Liste%20des%20etoiles%20doubles.pdf<\/span><\/a><\/p>\n<p><span style=\"color: #ff3366;\"><span style=\"font-size: large;\"><b>Les \u00e9toiles multiples <\/b><\/span><\/span><span style=\"font-size: large;\">: sont des syst\u00e8mes stellaires compos\u00e9s d&rsquo;au moins trois \u00e9toiles <\/span><span style=\"font-size: large;\">reli\u00e9es par la gravitation.<\/span><\/p>\n<p><span style=\"font-size: large;\">Voir ci-dessous la vue d&rsquo;artiste de HD 188753,un syst\u00e8me \u00e0 trois \u00e9toiles:<\/span><\/p>\n<p><span style=\"font-size: large;\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone  wp-image-552\" src=\"http:\/\/astroriom.net\/wp1\/wp-content\/uploads\/2018\/03\/etoiles_multiples-300x240.jpg\" alt=\"\" width=\"535\" height=\"432\" \/><\/span>\t\t<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Les \u00e9toiles variables : sont des \u00e9toiles dont l&rsquo;\u00e9clat varie au cours du temps, il en existe de diff\u00e9rents types. Les variables pulsantes : ce sont les variables les plus courantes ; ces \u00e9toiles pr\u00e9sentent une variation p\u00e9riodique de leur volume, ce qui engendre une modification de leur luminosit\u00e9 . Les variables par rotations : &hellip; <a href=\"http:\/\/astroriom.net\/v2\/?p=551\" class=\"more-link\">Lire la suite de <span class=\"screen-reader-text\">Les \u00e9toiles variables, doubles, multiples&#8230;<\/span><\/a><\/p>\n","protected":false},"author":4,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[22],"tags":[],"class_list":["post-551","post","type-post","status-publish","format-standard","hentry","category-etoiles","no-featured-image"],"_links":{"self":[{"href":"http:\/\/astroriom.net\/v2\/index.php?rest_route=\/wp\/v2\/posts\/551","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/astroriom.net\/v2\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/astroriom.net\/v2\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/astroriom.net\/v2\/index.php?rest_route=\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"http:\/\/astroriom.net\/v2\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=551"}],"version-history":[{"count":1,"href":"http:\/\/astroriom.net\/v2\/index.php?rest_route=\/wp\/v2\/posts\/551\/revisions"}],"predecessor-version":[{"id":1172,"href":"http:\/\/astroriom.net\/v2\/index.php?rest_route=\/wp\/v2\/posts\/551\/revisions\/1172"}],"wp:attachment":[{"href":"http:\/\/astroriom.net\/v2\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=551"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/astroriom.net\/v2\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=551"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/astroriom.net\/v2\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=551"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}