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aria-haspopup="true" data-event-name="ui.dropdown-vector-page-titlebar-toc" class="vector-dropdown-checkbox " aria-label="Basculer la table des matières" > <label id="vector-page-titlebar-toc-label" for="vector-page-titlebar-toc-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-listBullet mw-ui-icon-wikimedia-listBullet"></span> <span class="vector-dropdown-label-text">Basculer la table des matières</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-titlebar-toc-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <h1 id="firstHeading" class="firstHeading mw-first-heading"><span class="mw-page-title-main">Petit axe</span></h1> <div id="p-lang-btn" class="vector-dropdown mw-portlet mw-portlet-lang" > <input type="checkbox" id="p-lang-btn-checkbox" role="button" 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href="/w/index.php?title=Sp%C3%A9cial:Citer&page=Petit_axe&id=220706063&wpFormIdentifier=titleform" title="Informations sur la manière de citer cette page"><span>Citer cette page</span></a></li><li id="t-urlshortener" class="mw-list-item"><a href="/w/index.php?title=Sp%C3%A9cial:UrlShortener&url=https%3A%2F%2Ffr.wikipedia.org%2Fwiki%2FPetit_axe"><span>Obtenir l'URL raccourcie</span></a></li><li id="t-urlshortener-qrcode" class="mw-list-item"><a href="/w/index.php?title=Sp%C3%A9cial:QrCode&url=https%3A%2F%2Ffr.wikipedia.org%2Fwiki%2FPetit_axe"><span>Télécharger le code QR</span></a></li> </ul> </div> </div> <div id="p-coll-print_export" class="vector-menu mw-portlet mw-portlet-coll-print_export" > <div class="vector-menu-heading"> Imprimer / exporter </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="coll-create_a_book" class="mw-list-item"><a href="/w/index.php?title=Sp%C3%A9cial:Livre&bookcmd=book_creator&referer=Petit+axe"><span>Créer un livre</span></a></li><li id="coll-download-as-rl" class="mw-list-item"><a href="/w/index.php?title=Sp%C3%A9cial:DownloadAsPdf&page=Petit_axe&action=show-download-screen"><span>Télécharger comme PDF</span></a></li><li id="t-print" class="mw-list-item"><a href="/w/index.php?title=Petit_axe&printable=yes" title="Version imprimable de cette page [p]" accesskey="p"><span>Version imprimable</span></a></li> </ul> </div> </div> <div id="p-wikibase-otherprojects" class="vector-menu mw-portlet mw-portlet-wikibase-otherprojects" > <div class="vector-menu-heading"> Dans d’autres projets </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="t-wikibase" class="wb-otherproject-link wb-otherproject-wikibase-dataitem mw-list-item"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q21143682" title="Lien vers l’élément dans le dépôt de données connecté [g]" accesskey="g"><span>Élément Wikidata</span></a></li> </ul> </div> </div> </div> </div> </div> </div> </nav> </div> </div> </div> <div class="vector-column-end"> <div class="vector-sticky-pinned-container"> <nav class="vector-page-tools-landmark" aria-label="Outils de la page"> <div id="vector-page-tools-pinned-container" class="vector-pinned-container"> </div> </nav> <nav class="vector-appearance-landmark" aria-label="Apparence"> <div id="vector-appearance-pinned-container" class="vector-pinned-container"> <div id="vector-appearance" class="vector-appearance vector-pinnable-element"> <div class="vector-pinnable-header vector-appearance-pinnable-header vector-pinnable-header-pinned" data-feature-name="appearance-pinned" data-pinnable-element-id="vector-appearance" data-pinned-container-id="vector-appearance-pinned-container" data-unpinned-container-id="vector-appearance-unpinned-container" > <div class="vector-pinnable-header-label">Apparence</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-appearance.pin">déplacer vers la barre latérale</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-appearance.unpin">masquer</button> </div> </div> </div> </nav> </div> </div> <div id="bodyContent" class="vector-body" aria-labelledby="firstHeading" data-mw-ve-target-container> <div class="vector-body-before-content"> <div class="mw-indicators"> </div> <div id="siteSub" class="noprint">Un article de Wikipédia, l'encyclopédie libre.</div> </div> <div id="contentSub"><div id="mw-content-subtitle"></div></div> <div id="mw-content-text" class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="fr" dir="ltr"><div class="bandeau-container metadata bandeau-article bandeau-niveau-ebauche"><div class="bandeau-cell bandeau-icone" style="display:table-cell;padding-right:0.5em"><span class="noviewer" typeof="mw:File"><a href="/wiki/Fichier:Nuvola_apps_kfig.svg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/5/57/Nuvola_apps_kfig.svg/35px-Nuvola_apps_kfig.svg.png" decoding="async" width="35" height="35" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/5/57/Nuvola_apps_kfig.svg/53px-Nuvola_apps_kfig.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/5/57/Nuvola_apps_kfig.svg/69px-Nuvola_apps_kfig.svg.png 2x" data-file-width="109" data-file-height="110" /></a></span></div><div class="bandeau-cell" style="display:table-cell;padding-right:0.5em"> <p><strong class="bandeau-titre">Cet article est une <a href="/wiki/Aide:%C3%89bauche" title="Aide:Ébauche">ébauche</a> concernant la <a href="/wiki/G%C3%A9om%C3%A9trie" title="Géométrie">géométrie</a>.</strong> </p><p>Vous pouvez partager vos connaissances en l’améliorant (<b><a href="/wiki/Aide:Comment_modifier_une_page" title="Aide:Comment modifier une page">comment ?</a></b>) selon les recommandations des <a href="/wiki/Projet:Accueil" title="Projet:Accueil">projets correspondants</a>. </p> </div></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/Fichier:Ellipse_axis.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/7/70/Ellipse_axis.png/220px-Ellipse_axis.png" decoding="async" width="220" height="108" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/7/70/Ellipse_axis.png/330px-Ellipse_axis.png 1.5x, //upload.wikimedia.org/wikipedia/commons/7/70/Ellipse_axis.png 2x" data-file-width="353" data-file-height="173" /></a><figcaption><b>Petit axe</b> d'une ellipse (en mauve)<br />Grand axe (en vert)<br /><b>b</b> est le demi-petit axe<br /><b>a</b> le demi-grand axe.</figcaption></figure> <p><span id="Petite_axe"></span> Le <b>petit axe</b> d'une <a href="/wiki/Ellipse_(math%C3%A9matiques)" title="Ellipse (mathématiques)">ellipse</a> est le <a href="/wiki/Segment_(math%C3%A9matiques)" title="Segment (mathématiques)">segment</a> porté par la <a href="/wiki/Droite_(math%C3%A9matiques)" title="Droite (mathématiques)">droite</a> passant par le centre de l'ellipse et perpendiculaire au <a href="/wiki/Grand_axe" title="Grand axe">grand axe</a> de celle-ci. </p><p>Il traverse l'ellipse à mi-chemin entre ses <a href="/wiki/Foyer_(math%C3%A9matiques)" title="Foyer (mathématiques)">foyers</a> et <a href="/wiki/Perpendiculaire" class="mw-redirect" title="Perpendiculaire">perpendiculairement</a> à la ligne qui lie ceux-ci. </p><p>Le diamètre perpendiculaire, qui traverse l'ellipse en traversant ses foyers, est son <a href="/wiki/Grand_axe" title="Grand axe">grand axe</a>. </p><p>Le <b>demi-petit axe</b> est la moitié du petit axe et s'étend depuis le centre de l'ellipse jusqu'à l'un ou l'autre des points les plus rapprochés. </p><p>Les axes sont les équivalents pour l'ellipse des <a href="/wiki/Diam%C3%A8tre" title="Diamètre">diamètres</a> d'un <a href="/wiki/Cercle" title="Cercle">cercle</a>, tandis que les demi-axes sont les équivalents pour l'ellipse des <a href="/wiki/Rayon_(g%C3%A9om%C3%A9trie)" title="Rayon (géométrie)">rayons</a>. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Étymologie"><span id=".C3.89tymologie"></span>Étymologie</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Petit_axe&veaction=edit&section=1" title="Modifier la section : Étymologie" class="mw-editsection-visualeditor"><span>modifier</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Petit_axe&action=edit&section=1" title="Modifier le code source de la section : Étymologie"><span>modifier le code</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>La désignation de « petit axe » vient du <a href="/wiki/Latin" title="Latin">latin</a> <i><span class="lang-la" lang="la">minor axis</span></i>, ainsi désigné parce que la droite dont le petit axe est un segment est un <a href="/wiki/Sym%C3%A9trie_(transformation_g%C3%A9om%C3%A9trique)" title="Symétrie (transformation géométrique)">axe de symétrie</a> de l'ellipse et que la distance entre les deux extrémités de ce segment est plus courte que celle entre les deux extrémités du grand axe. </p> <div class="mw-heading mw-heading2"><h2 id="Notations">Notations</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Petit_axe&veaction=edit&section=2" title="Modifier la section : Notations" class="mw-editsection-visualeditor"><span>modifier</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Petit_axe&action=edit&section=2" title="Modifier le code source de la section : Notations"><span>modifier le code</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>La longueur du petit axe est couramment notée <span class="texhtml">2<i>b</i></span>, celle du demi-petit axe, <span class="texhtml mvar" style="font-style:italic;">b</span>. </p> <div class="mw-heading mw-heading2"><h2 id="Propriétés"><span id="Propri.C3.A9t.C3.A9s"></span>Propriétés</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Petit_axe&veaction=edit&section=3" title="Modifier la section : Propriétés" class="mw-editsection-visualeditor"><span>modifier</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Petit_axe&action=edit&section=3" title="Modifier le code source de la section : Propriétés"><span>modifier le code</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Le petit axe est <a href="/wiki/Parall%C3%A9lisme_(g%C3%A9om%C3%A9trie)" title="Parallélisme (géométrie)">parallèle</a> : </p> <ul><li>au <a href="/wiki/C%C3%B4t%C3%A9_droit" title="Côté droit">côté droit</a> de l'ellipse, corde passant par le foyer de la conique, perpendiculaire à son grand axe et dont les extrémités sont deux points de la courbe ;</li> <li>à la directrice de l'ellipse.</li></ul> <p>Il est perpendiculaire au grand axe. </p><p>Les extrémités du petit axe sont les points où la courbure de l'ellipse est minimale. </p> <div class="mw-heading mw-heading2"><h2 id="Calcul">Calcul</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Petit_axe&veaction=edit&section=4" title="Modifier la section : Calcul" class="mw-editsection-visualeditor"><span>modifier</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Petit_axe&action=edit&section=4" title="Modifier le code source de la section : Calcul"><span>modifier le code</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>La longueur du demi-petit axe d'une ellipse peut être obtenue par les formules suivantes : </p> <dl><dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle b=a{\sqrt {1-e^{2}}}={\sqrt {a^{2}-c^{2}}}={eh \over {\sqrt {1-e^{2}}}}={\sqrt {ap}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>b</mi> <mo>=</mo> <mi>a</mi> <mrow class="MJX-TeXAtom-ORD"> <msqrt> <mn>1</mn> <mo>−</mo> <msup> <mi>e</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> </msqrt> </mrow> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <msqrt> <msup> <mi>a</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> <mo>−</mo> <msup> <mi>c</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> </msqrt> </mrow> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <mi>e</mi> <mi>h</mi> </mrow> <mrow class="MJX-TeXAtom-ORD"> <msqrt> <mn>1</mn> <mo>−</mo> <msup> <mi>e</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> </msqrt> </mrow> </mfrac> </mrow> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <msqrt> <mi>a</mi> <mi>p</mi> </msqrt> </mrow> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle b=a{\sqrt {1-e^{2}}}={\sqrt {a^{2}-c^{2}}}={eh \over {\sqrt {1-e^{2}}}}={\sqrt {ap}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/df3eb88e1bdbd95f1ee909ff4e13e540a12b269f" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -3.171ex; width:46.23ex; height:6.676ex;" alt="{\displaystyle b=a{\sqrt {1-e^{2}}}={\sqrt {a^{2}-c^{2}}}={eh \over {\sqrt {1-e^{2}}}}={\sqrt {ap}}}"></span></dd></dl> <p>dans lesquelles : </p> <ul><li><span class="texhtml mvar" style="font-style:italic;">a</span> est la longueur du demi-grand axe de l'ellipse ;</li> <li><span class="texhtml mvar" style="font-style:italic;">e</span> est son <a href="/wiki/Excentricit%C3%A9_(math%C3%A9matiques)" title="Excentricité (mathématiques)">excentricité</a> ;</li> <li><span class="texhtml mvar" style="font-style:italic;">c</span> est son excentricité linéaire ;</li> <li><span class="texhtml mvar" style="font-style:italic;">h</span> est la distance séparant un foyer F de l'ellipse de la directrice (d) associée à ce foyer ;</li> <li><span class="texhtml mvar" style="font-style:italic;">p</span> est la longueur du demi-paramètre de l'ellipse.</li></ul> <div class="mw-heading mw-heading2"><h2 id="Extension_aux_autres_coniques">Extension aux autres coniques</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Petit_axe&veaction=edit&section=5" title="Modifier la section : Extension aux autres coniques" class="mw-editsection-visualeditor"><span>modifier</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Petit_axe&action=edit&section=5" title="Modifier le code source de la section : Extension aux autres coniques"><span>modifier le code</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Le cercle est une <a href="/wiki/Conique" title="Conique">conique</a> d'excentricité nulle. Par suite, dans le cas du cercle : </p> <dl><dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle d=2r=2a=2b.}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>d</mi> <mo>=</mo> <mn>2</mn> <mi>r</mi> <mo>=</mo> <mn>2</mn> <mi>a</mi> <mo>=</mo> <mn>2</mn> <mi>b</mi> <mo>.</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle d=2r=2a=2b.}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/604c75ea1de183631f76e8f6f0a6f2fa0e834957" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:17.921ex; height:2.176ex;" alt="{\displaystyle d=2r=2a=2b.}"></span></dd></dl> <p>L'<a href="/wiki/Hyperbole_(math%C3%A9matiques)" title="Hyperbole (mathématiques)">hyperbole</a> est une conique d'excentricité strictement supérieure à 1. Par extension, la pente des <a href="/wiki/Asymptote" title="Asymptote">asymptotes</a> d'une hyperbole avec son axe focal est couramment notée <span class="texhtml"><i>b</i>/<i>a</i></span>. Par suite, dans le cas d'une hyperbole, la distance <span class="texhtml mvar" style="font-style:italic;">b</span> peut être obtenue par les formules suivantes : </p> <dl><dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle b=a{\sqrt {e^{2}-1}}={\sqrt {c^{2}-a^{2}}}={eh \over {\sqrt {e^{2}-1}}}={\sqrt {ap}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>b</mi> <mo>=</mo> <mi>a</mi> <mrow class="MJX-TeXAtom-ORD"> <msqrt> <msup> <mi>e</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> <mo>−</mo> <mn>1</mn> </msqrt> </mrow> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <msqrt> <msup> <mi>c</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> <mo>−</mo> <msup> <mi>a</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> </msqrt> </mrow> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <mi>e</mi> <mi>h</mi> </mrow> <mrow class="MJX-TeXAtom-ORD"> <msqrt> <msup> <mi>e</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> <mo>−</mo> <mn>1</mn> </msqrt> </mrow> </mfrac> </mrow> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <msqrt> <mi>a</mi> <mi>p</mi> </msqrt> </mrow> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle b=a{\sqrt {e^{2}-1}}={\sqrt {c^{2}-a^{2}}}={eh \over {\sqrt {e^{2}-1}}}={\sqrt {ap}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/0003c3cc86d505901434faf92b020def4922c951" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -3.171ex; width:46.23ex; height:6.676ex;" alt="{\displaystyle b=a{\sqrt {e^{2}-1}}={\sqrt {c^{2}-a^{2}}}={eh \over {\sqrt {e^{2}-1}}}={\sqrt {ap}}}"></span>.</dd></dl> <div class="mw-heading mw-heading2"><h2 id="Astronomie">Astronomie</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Petit_axe&veaction=edit&section=6" title="Modifier la section : Astronomie" class="mw-editsection-visualeditor"><span>modifier</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Petit_axe&action=edit&section=6" title="Modifier le code source de la section : Astronomie"><span>modifier le code</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>En <a href="/wiki/Astronomie" title="Astronomie">astronomie</a>, le petit axe de l'<a href="/wiki/Orbite_de_la_Terre" title="Orbite de la Terre">orbite de la Terre</a> est un segment de la ligne des <a href="/wiki/Solstice" title="Solstice">solstices</a>. </p> <div class="navbox-container" style="clear:both;"> <table class="navbox collapsible noprint autocollapse" style=""> <tbody><tr><th class="navbox-title" colspan="2" style=""><div style="float:left; width:6em; text-align:left"><div class="noprint plainlinks nowrap tnavbar" style="padding:0; font-size:xx-small; color:var(--color-emphasized, #000000);"><a href="/wiki/Mod%C3%A8le:Palette_Orbites" title="Modèle:Palette Orbites"><abbr class="abbr" title="Voir ce modèle.">v</abbr></a> · <a class="external text" href="https://fr.wikipedia.org/w/index.php?title=Mod%C3%A8le:Palette_Orbites&action=edit"><abbr class="abbr" title="Modifier ce modèle. Merci de prévisualiser avant de sauvegarder.">m</abbr></a></div></div><div style="font-size:110%"><a href="/wiki/Orbite" title="Orbite">Orbites</a></div></th> </tr> <tr> <th class="navbox-group" style="">Général</th> <td class="navbox-list" style=""><div class="liste-horizontale"> <ul><li><a href="/wiki/Orbite_en_bo%C3%AEte" title="Orbite en boîte">Orbite en boîte</a></li> <li><a href="/wiki/Orbite_circulaire" title="Orbite circulaire">Circulaire</a></li> <li><a href="/wiki/Orbite_d%27attente" title="Orbite d'attente">Orbite d'attente</a></li> <li><a href="/wiki/Trajectoire_parabolique" title="Trajectoire parabolique">Orbite d'évasion</a></li> <li><a href="/wiki/Orbite_de_rebut" title="Orbite de rebut">Orbite de rebut</a></li> <li><a href="/wiki/Orbite_elliptique" title="Orbite elliptique">Elliptique</a> <ul><li><a href="/wiki/Orbite_elliptique_%C3%A9lev%C3%A9e" title="Orbite elliptique élevée">Elliptique élevée</a></li></ul></li> <li><a href="/wiki/Orbite_inclin%C3%A9e" title="Orbite inclinée">Orbite inclinée</a></li> <li><a href="/wiki/Orbite_non_inclin%C3%A9e" title="Orbite non inclinée">Orbite non inclinée</a></li> <li><a href="/wiki/Orbite_osculatrice" title="Orbite osculatrice">Osculatrice</a></li> <li><a href="/wiki/Orbite_synchrone" title="Orbite synchrone">Synchrone</a> <ul><li><a href="/wiki/Orbite_semi-synchrone" title="Orbite semi-synchrone">Semi-synchrone</a></li> <li><a href="/wiki/Orbite_sous-synchrone" title="Orbite sous-synchrone">Sous-synchrone</a></li> <li><a href="/wiki/Orbite_super-synchrone" title="Orbite super-synchrone">Super-synchrone</a></li></ul></li> <li><a href="/wiki/Trajectoire_hyperbolique" title="Trajectoire hyperbolique">Trajectoire hyperbolique</a></li> <li><a href="/wiki/Trajectoire_parabolique" title="Trajectoire parabolique">Trajectoire parabolique</a> (capture)</li></ul> </div></td> </tr> <tr> <th class="navbox-group" style=""><a href="/wiki/Orbite_terrestre" title="Orbite terrestre">Géocentrique</a></th> <td class="navbox-list navbox-even" style=""><div class="liste-horizontale"> <ul><li><a href="/wiki/Orbite_h%C3%A9liosynchrone" title="Orbite héliosynchrone">Orbite héliosynchrone</a></li> <li><a href="/wiki/Orbite_g%C3%A9ostationnaire" title="Orbite géostationnaire">Géostationnaire</a></li> <li><a href="/wiki/Orbite_g%C3%A9osynchrone" title="Orbite géosynchrone">Géosynchrone</a></li> <li><a href="/wiki/Orbite_de_Molnia" title="Orbite de Molnia">Orbite de Molnia</a></li> <li><a href="/wiki/Orbite_polaire" title="Orbite polaire">Polaire</a></li> <li><a href="/wiki/Orbite_quasi_%C3%A9quatoriale" title="Orbite quasi équatoriale">Quasi équatoriale</a></li> <li><a href="/wiki/Orbite_terrestre_basse" title="Orbite terrestre basse">Terrestre basse</a></li> <li><a href="/wiki/Orbite_terrestre_moyenne" title="Orbite terrestre moyenne">Terrestre moyenne</a></li> <li><a href="/wiki/Orbite_terrestre_haute" title="Orbite terrestre haute">Terrestre haute</a></li> <li><a href="/wiki/Orbite_toundra" title="Orbite toundra">Toundra</a></li></ul> </div></td> </tr> <tr> <th class="navbox-group" style="">Non géocentrique</th> <td class="navbox-list" style=""><div class="liste-horizontale"> <ul><li><a href="/wiki/Orbite_ar%C3%A9ocentrique" title="Orbite aréocentrique">Aréocentrique</a> <ul><li><a href="/wiki/Orbite_ar%C3%A9osynchrone" title="Orbite aréosynchrone">Aréosynchrone</a></li> <li><a href="/wiki/Orbite_ar%C3%A9ostationnaire" title="Orbite aréostationnaire">Aréostationnaire</a></li></ul></li> <li><a href="/wiki/Orbite_de_halo" title="Orbite de halo">Halo</a></li> <li><a href="/wiki/Orbite_h%C3%A9liocentrique" title="Orbite héliocentrique">Héliocentrique</a> <ul><li><a href="/wiki/Orbite_h%C3%A9liostationnaire" title="Orbite héliostationnaire">Héliostationnaire</a></li></ul></li> <li><a href="/wiki/Orbite_de_Lissajous" title="Orbite de Lissajous">Lissajous</a></li> <li><a href="/wiki/Orbite_s%C3%A9l%C3%A9nocentrique" title="Orbite sélénocentrique">Sélénocentrique</a></li></ul> </div></td> </tr> <tr> <th class="navbox-group" style="">Paramètres</th> <td class="navbox-list navbox-even" style=""><table class="navbox-subgroup" style=""> <tbody><tr> <th class="navbox-group" style="width:50px;">Classiques</th> <td class="navbox-list" style="text-align:left;;"><div class="liste-horizontale"> <ul><li><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle M_{o}\,\!}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>M</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>o</mi> </mrow> </msub> <mspace width="thinmathspace" /> <mspace width="negativethinmathspace" /> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle M_{o}\,\!}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/27280153fdde274f27fcbf67ab81b21c50f5eadb" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; margin-right: -0.387ex; width:3.671ex; height:2.509ex;" alt="{\displaystyle M_{o}\,\!}"></span> <a href="/wiki/Anomalie_moyenne" title="Anomalie moyenne">Anomalie moyenne</a> à l'<a href="/wiki/%C3%89poque_(astronomie)" title="Époque (astronomie)">époque</a></li> <li><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \omega \,\!}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>ω</mi> <mspace width="thinmathspace" /> <mspace width="negativethinmathspace" /> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \omega \,\!}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/92658a4da1783d12cb53c1fffc24b29b4963f20f" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; margin-right: -0.387ex; width:1.833ex; height:1.676ex;" alt="{\displaystyle \omega \,\!}"></span> <a href="/wiki/Argument_du_p%C3%A9riastre" title="Argument du périastre">Argument du périastre</a></li> <li><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle a\,\!}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>a</mi> <mspace width="thinmathspace" /> <mspace width="negativethinmathspace" /> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle a\,\!}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/99a94f96d2455b9d7faf3cec3eb02ab3c455aec1" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; margin-right: -0.387ex; width:1.617ex; height:1.676ex;" alt="{\displaystyle a\,\!}"></span> <a href="/wiki/Grand_axe" title="Grand axe">Demi-grand axe</a></li> <li><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle e\,\!}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>e</mi> <mspace width="thinmathspace" /> <mspace width="negativethinmathspace" /> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle e\,\!}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/32308a9beabe5e8a2c683aa285cfd6e8abafb02c" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; margin-right: -0.387ex; width:1.471ex; height:1.676ex;" alt="{\displaystyle e\,\!}"></span> <a href="/wiki/Excentricit%C3%A9_orbitale" title="Excentricité orbitale">Excentricité</a></li> <li><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle i\,\!}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>i</mi> <mspace width="thinmathspace" /> <mspace width="negativethinmathspace" /> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle i\,\!}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/ea0042f70417500ed06b77bf2b87ef913cd3127b" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; margin-right: -0.387ex; width:1.19ex; height:2.176ex;" alt="{\displaystyle i\,\!}"></span> <a href="/wiki/Inclinaison_orbitale" title="Inclinaison orbitale">Inclinaison</a></li> <li><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \Omega \,\!}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi mathvariant="normal">Ω</mi> <mspace width="thinmathspace" /> <mspace width="negativethinmathspace" /> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \Omega \,\!}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/93847015f621d7ad9940329db05ee4cfa7ee0689" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; margin-right: -0.387ex; width:2.065ex; height:2.176ex;" alt="{\displaystyle \Omega \,\!}"></span> <a href="/wiki/Longitude_du_n%C5%93ud_ascendant" title="Longitude du nœud ascendant">Longitude du nœud ascendant</a></li></ul> </div></td> </tr> <tr> <th class="navbox-group" style="width:50px;">Autres</th> <td class="navbox-list navbox-even" style="text-align:left;;"><div class="liste-horizontale"> <ul><li><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle E\,\!}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>E</mi> <mspace width="thinmathspace" /> <mspace width="negativethinmathspace" /> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle E\,\!}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/1592db19e68e9789c5ed320d611f7c9a328341cd" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; margin-right: -0.387ex; width:2.163ex; height:2.176ex;" alt="{\displaystyle E\,\!}"></span> <a href="/wiki/Anomalie_excentrique" title="Anomalie excentrique">Anomalie excentrique</a></li> <li><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \nu \,\!}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>ν</mi> <mspace width="thinmathspace" /> <mspace width="negativethinmathspace" /> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \nu \,\!}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/817715b4ce1e4f00fa003b902c5d71ad172df22e" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; margin-right: -0.387ex; width:1.619ex; height:1.676ex;" alt="{\displaystyle \nu \,\!}"></span> <a href="/wiki/Anomalie_vraie" title="Anomalie vraie">Anomalie vraie</a></li> <li><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle b\,\!}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>b</mi> <mspace width="thinmathspace" /> <mspace width="negativethinmathspace" /> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle b\,\!}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/cb1dfcc2fcd791aacf48286147257b507b009e78" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; margin-right: -0.387ex; width:1.385ex; height:2.176ex;" alt="{\displaystyle b\,\!}"></span> <a class="mw-selflink selflink">Demi-petit axe</a></li> <li><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \epsilon \,\!}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>ϵ</mi> <mspace width="thinmathspace" /> <mspace width="negativethinmathspace" /> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \epsilon \,\!}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/0908a81825c617639f3401ee1f29c4aae45b5c78" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; margin-right: -0.387ex; width:1.331ex; height:1.676ex;" alt="{\displaystyle \epsilon \,\!}"></span> <a href="/wiki/Excentricit%C3%A9_(math%C3%A9matiques)" title="Excentricité (mathématiques)">Excentricité</a></li> <li><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle L\,\!}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>L</mi> <mspace width="thinmathspace" /> <mspace width="negativethinmathspace" /> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle L\,\!}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/09a0c8422640181668bbefa6f5d5481dbc1f03df" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; margin-right: -0.387ex; width:1.97ex; height:2.176ex;" alt="{\displaystyle L\,\!}"></span> <a href="/wiki/Longitude_moyenne" title="Longitude moyenne">Longitude moyenne</a></li> <li><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle l\,\!}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>l</mi> <mspace width="thinmathspace" /> <mspace width="negativethinmathspace" /> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle l\,\!}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/b29435a849761c988f6c160c9e8bd9dda302c319" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; margin-right: -0.387ex; width:1.08ex; height:2.176ex;" alt="{\displaystyle l\,\!}"></span> <a href="/wiki/Longitude_vraie" title="Longitude vraie">Longitude vraie</a></li> <li><a href="/wiki/Param%C3%A8tres_orbitaux_%C3%A0_deux_lignes" title="Paramètres orbitaux à deux lignes">Paramètres orbitaux à deux lignes</a></li> <li><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle T\,\!}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>T</mi> <mspace width="thinmathspace" /> <mspace width="negativethinmathspace" /> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle T\,\!}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/8e6be5af8259cedf1aac5ae3f6a5fad65ec2ef87" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; margin-right: -0.387ex; width:2.023ex; height:2.176ex;" alt="{\displaystyle T\,\!}"></span> <a href="/wiki/P%C3%A9riode_de_r%C3%A9volution" title="Période de révolution">Période orbitale</a></li></ul> </div></td> </tr> </tbody></table></td> </tr> <tr> <th class="navbox-group" style=""><a href="/wiki/Man%C5%93uvre_orbitale" title="Manœuvre orbitale">Manœuvres</a></th> <td class="navbox-list" style=""><div class="liste-horizontale"> <ul><li><a href="/wiki/A%C3%A9rofreinage" title="Aérofreinage">Aérofreinage</a></li> <li><a href="/wiki/Assistance_gravitationnelle" title="Assistance gravitationnelle">Assistance gravitationnelle</a></li> <li><a href="/wiki/Capture_balistique" title="Capture balistique">Capture balistique</a></li> <li><a href="/wiki/Bilan_des_modifications_du_vecteur_vitesse" title="Bilan des modifications du vecteur vitesse">Bilan des modifications du vecteur vitesse</a></li> <li><a href="/wiki/Correction_d%27inclinaison" title="Correction d'inclinaison">Correction d'inclinaison</a></li> <li><a href="/wiki/Correction_du_phasage" title="Correction du phasage">Correction du phasage</a></li> <li><a href="/wiki/Effet_Oberth" title="Effet Oberth">Effet Oberth</a></li> <li><a href="/wiki/%C3%89vitement_de_collision" title="Évitement de collision">Évitement de collision</a></li> <li><a href="/wiki/Orbite_de_transfert_g%C3%A9ostationnaire" title="Orbite de transfert géostationnaire">Orbite de transfert géostationnaire</a></li> <li><a href="/wiki/Rendez-vous_spatial" title="Rendez-vous spatial">Rendez-vous</a></li> <li><a href="/wiki/Rotation_gravitationnelle" title="Rotation gravitationnelle">Rotation gravitationnelle</a> (Trajectoire à incidence nulle)</li> <li><a href="/wiki/Transfert_%C3%A0_faible_%C3%A9nergie" title="Transfert à faible énergie">Transfert à faible énergie</a></li> <li><a href="/wiki/Transfert_bi-elliptique" title="Transfert bi-elliptique">Transfert bi-elliptique</a></li> <li><a href="/wiki/Orbite_de_transfert#Orbite_de_transfert_de_Hohmann" title="Orbite de transfert">Transfert de Hohmann</a></li> <li><a href="/wiki/Transposition,_amarrage_et_extraction" title="Transposition, amarrage et extraction">Transposition, amarrage et extraction</a></li></ul> </div></td> </tr> <tr> <th class="navbox-group" style="">Mécanique<br />orbitale</th> <td class="navbox-list navbox-even" style=""><div class="liste-horizontale"> <ul><li><a href="/wiki/Apside" title="Apside">Apsides</a> <ul><li><a href="/wiki/P%C3%A9riapside" title="Périapside">Périapside</a></li> <li><a href="/wiki/Apoapside" title="Apoapside">Apoapside</a></li></ul></li> <li><a href="/wiki/%C3%89nergie_orbitale_sp%C3%A9cifique" title="Énergie orbitale spécifique">Énergie orbitale spécifique</a></li> <li><a href="/wiki/%C3%89poque_(astronomie)" title="Époque (astronomie)">Époque</a></li> <li><a href="/wiki/%C3%89ph%C3%A9m%C3%A9ride_(astronomie)" title="Éphéméride (astronomie)">Éphéméride</a></li> <li><a href="/wiki/%C3%89quation_de_Kepler" title="Équation de Kepler">Équation de Kepler</a></li> <li><a href="/wiki/%C3%89quation_d%27orbite" title="Équation d'orbite">Équation d'orbite</a></li> <li><a href="/wiki/Lois_de_Kepler" title="Lois de Kepler">Lois de Kepler</a></li> <li><a href="/wiki/Moment_cin%C3%A9tique_sp%C3%A9cifique" title="Moment cinétique spécifique">Moment cinétique spécifique</a></li> <li><a href="/wiki/Mouvement_k%C3%A9pl%C3%A9rien" title="Mouvement képlérien">Mouvement képlérien</a></li> <li><a href="/wiki/Mouvement_prograde_ou_r%C3%A9trograde" title="Mouvement prograde ou rétrograde">Rétrograde</a></li> <li><a href="/wiki/Perturbation_(astronomie)" title="Perturbation (astronomie)">Perturbation</a></li> <li><a href="/wiki/Point_de_Lagrange" title="Point de Lagrange">Point de Lagrange</a></li> <li><a href="/wiki/Probl%C3%A8me_%C3%A0_N_corps" title="Problème à N corps">Problème à N corps</a></li> <li><a href="/wiki/Probl%C3%A8me_%C3%A0_deux_corps" title="Problème à deux corps">Problème à deux corps</a></li> <li><a href="/wiki/R%C3%A9seau_de_transport_interplan%C3%A9taire" title="Réseau de transport interplanétaire">Réseau de transport interplanétaire</a></li> <li><a href="/wiki/Syst%C3%A8me_de_coordonn%C3%A9es_%C3%A9quatoriales" title="Système de coordonnées équatoriales">Système de coordonnées équatoriales</a></li> <li><a href="/wiki/Syst%C3%A8me_de_coordonn%C3%A9es_c%C3%A9lestes" title="Système de coordonnées célestes">Système de coordonnées célestes</a></li> <li><a href="/wiki/Trace_au_sol" title="Trace au sol">Trace au sol</a></li> <li><a href="/wiki/Trou_de_serrure_gravitationnel" title="Trou de serrure gravitationnel">Trou de serrure gravitationnel</a></li> <li><a href="/wiki/Vecteur_d%27%C3%A9tat_orbital" title="Vecteur d'état orbital">Vecteur d'état orbital</a></li> <li><a href="/wiki/Vitesse_de_lib%C3%A9ration" title="Vitesse de libération">Vitesse de libération</a></li> <li><a href="/wiki/Vitesse_orbitale" title="Vitesse orbitale">Vitesse orbitale</a></li></ul> </div></td> </tr> <tr> <td class="navbox-banner" style="" colspan="2"><a href="/wiki/Liste_d%27orbites" title="Liste d'orbites">Liste d'orbites</a></td></tr></tbody></table> </div> <ul id="bandeau-portail" class="bandeau-portail"><li><span class="bandeau-portail-element"><span class="bandeau-portail-icone"><span class="noviewer" typeof="mw:File"><a href="/wiki/Portail:G%C3%A9om%C3%A9trie" title="Portail de la géométrie"><img alt="icône décorative" 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