{"id":630,"date":"2014-07-04T09:07:34","date_gmt":"2014-07-04T08:07:34","guid":{"rendered":"http:\/\/bibnum.hypotheses.org\/?p=630"},"modified":"2014-12-26T10:26:01","modified_gmt":"2014-12-26T09:26:01","slug":"la-mesure-du-diametre-des-etoiles-1851","status":"publish","type":"post","link":"https:\/\/bibnum.hypotheses.org\/630","title":{"rendered":"La mesure du diam\u00e8tre des \u00e9toiles (1851)"},"content":{"rendered":"<p><a href=\"http:\/\/bibnum.hypotheses.org\/files\/2014\/07\/Imagette-retaillee.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"alignleft size-full wp-image-631\" alt=\"Imagette-retaillee\" src=\"http:\/\/bibnum.hypotheses.org\/files\/2014\/07\/Imagette-retaillee.jpg\" width=\"75\" height=\"67\" srcset=\"https:\/\/bibnum.hypotheses.org\/files\/2014\/07\/Imagette-retaillee.jpg 75w, https:\/\/bibnum.hypotheses.org\/files\/2014\/07\/Imagette-retaillee-50x44.jpg 50w\" sizes=\"auto, (max-width: 75px) 100vw, 75px\" \/><\/a>D\u00e8s 1851, Hippolyte Fizeau r\u00e9alise que l\u2019on pourrait mesurer par interf\u00e9rom\u00e9trie le diam\u00e8tre apparent des \u00e9toiles en d\u00e9coupant avec deux diaphragmes plac\u00e9s devant l\u2019objectif d\u2019une lunette ou d\u2019un t\u00e9lescope deux parties de la lumi\u00e8re re\u00e7ue de l\u2019\u00e9toile et en faisant interf\u00e9rer ces deux faisceaux. Mais il ne publie cette id\u00e9e qu\u2019en 1868 sous la forme d\u2019une simple remarque. En 1873-1874 \u00c9douard Stephan la met en application avec le t\u00e9lescope de 80 cm de diam\u00e8tre de l\u2019Observatoire de Marseille, pour constater qu\u2019aucune des \u00e9toiles qu\u2019il observe n\u2019est r\u00e9solue. Puis elle est utilis\u00e9e avec succ\u00e8s par Albert A. Michelson en 1891 et par Maurice Hamy en 1898 pour mesurer le diam\u00e8tre apparent des satellites de Jupiter, et en 1895 par Karl Schwarzschild pour d\u00e9terminer la s\u00e9paration entre les composantes d\u2019\u00e9toiles doubles. Ce n\u2019est qu\u2019en 1920 que Michelson et Francis G. Pease parviennent \u00e0 mesurer ainsi le diam\u00e8tre de B\u00e9telgeuse. Puis la m\u00e9thode est en sommeil jusqu\u2019\u00e0 ce qu\u2019elle soit remise d\u2019actualit\u00e9 sous une forme diff\u00e9rente en 1956 par Robert Hanbury Brown et Richard Q. Twiss, puis sous sa forme initiale en 1974 par Antoine Labeyrie. Elle est aujourd\u2019hui en plein essor, avec au moins 12 interf\u00e9rom\u00e8tres optiques sp\u00e9cialis\u00e9s dans le monde.<\/p>\n<p>L&#8217;analyse est r\u00e9alis\u00e9e par James Lequeux, astronome \u00e9m\u00e9rite \u00e0 l\u2019Observatoire de Paris (<a href=\"http:\/\/www.bibnum.education.fr\/physique\/astronomie\/la-mesure-du-diametre-des-etoiles\" target=\"_blank\">BibNum<\/a>).<\/p>\n","protected":false},"excerpt":{"rendered":"<p>D\u00e8s 1851, Hippolyte Fizeau r\u00e9alise que l\u2019on pourrait mesurer par interf\u00e9rom\u00e9trie le diam\u00e8tre apparent des \u00e9toiles en d\u00e9coupant avec deux diaphragmes plac\u00e9s devant l\u2019objectif d\u2019une lunette ou d\u2019un t\u00e9lescope deux parties de la lumi\u00e8re&#46;&#46;&#46;<\/p>\n","protected":false},"author":1232,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_license":"","publish_to_discourse":"","publish_post_category":"","wpdc_auto_publish_overridden":"","wpdc_topic_tags":"","wpdc_pin_topic":"","wpdc_pin_until":"","discourse_post_id":"","discourse_permalink":"","wpdc_publishing_response":"","wpdc_publishing_error":"","footnotes":""},"categories":[63436],"tags":[],"ppma_author":[1081808],"class_list":["post-630","post","type-post","status-publish","format-standard","hentry","category-resumes-darticles-bibnum"],"authors":[{"term_id":1081808,"user_id":1232,"is_guest":0,"slug":"bibnum","display_name":"Bibnum","avatar_url":"https:\/\/secure.gravatar.com\/avatar\/8fb9cba24aad93a4be14d94a9f3f42d2133de7bb1b7c7a7990bd79816e1c31e4?s=96&d=blank&r=g","1":"","2":"","3":"","4":"","5":"","6":"","7":"","8":""}],"_links":{"self":[{"href":"https:\/\/bibnum.hypotheses.org\/wp-json\/wp\/v2\/posts\/630","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/bibnum.hypotheses.org\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/bibnum.hypotheses.org\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/bibnum.hypotheses.org\/wp-json\/wp\/v2\/users\/1232"}],"replies":[{"embeddable":true,"href":"https:\/\/bibnum.hypotheses.org\/wp-json\/wp\/v2\/comments?post=630"}],"version-history":[{"count":2,"href":"https:\/\/bibnum.hypotheses.org\/wp-json\/wp\/v2\/posts\/630\/revisions"}],"predecessor-version":[{"id":635,"href":"https:\/\/bibnum.hypotheses.org\/wp-json\/wp\/v2\/posts\/630\/revisions\/635"}],"wp:attachment":[{"href":"https:\/\/bibnum.hypotheses.org\/wp-json\/wp\/v2\/media?parent=630"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/bibnum.hypotheses.org\/wp-json\/wp\/v2\/categories?post=630"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/bibnum.hypotheses.org\/wp-json\/wp\/v2\/tags?post=630"},{"taxonomy":"author","embeddable":true,"href":"https:\/\/bibnum.hypotheses.org\/wp-json\/wp\/v2\/ppma_author?post=630"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}