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href="#Oscillation"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.3</span> <span>Oscillation</span> </div> </a> <ul id="toc-Oscillation-sublist" class="vector-toc-list"> <li id="toc-Short_term" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Short_term"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.3.1</span> <span>Short term</span> </div> </a> <ul id="toc-Short_term-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Long_term" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Long_term"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.3.2</span> <span>Long term</span> </div> </a> <ul id="toc-Long_term-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> </ul> </li> <li id="toc-Solar_System_bodies" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Solar_System_bodies"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>Solar System bodies</span> </div> </a> <ul id="toc-Solar_System_bodies-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Extrasolar_planets" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Extrasolar_planets"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>Extrasolar planets</span> </div> </a> <ul id="toc-Extrasolar_planets-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-See_also" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#See_also"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</span> <span>See also</span> </div> </a> <ul id="toc-See_also-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-References" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</span> <span>References</span> </div> </a> <ul id="toc-References-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-External_links" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#External_links"> <div class="vector-toc-text"> <span class="vector-toc-numb">7</span> <span>External links</span> </div> </a> <ul id="toc-External_links-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div class="mw-content-container"> <main id="content" class="mw-body"> <header class="mw-body-header vector-page-titlebar"> <nav aria-label="Contents" class="vector-toc-landmark"> <div id="vector-page-titlebar-toc" class="vector-dropdown vector-page-titlebar-toc vector-button-flush-left" > <input type="checkbox" id="vector-page-titlebar-toc-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-titlebar-toc" class="vector-dropdown-checkbox " aria-label="Toggle the table of contents" > <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">Toggle the table of contents</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">Axial tilt</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" aria-haspopup="true" data-event-name="ui.dropdown-p-lang-btn" class="vector-dropdown-checkbox mw-interlanguage-selector" aria-label="Go to an article in another language. Available in 61 languages" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-61" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">61 languages</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-af mw-list-item"><a href="https://af.wikipedia.org/wiki/Ashelling" title="Ashelling – Afrikaans" lang="af" hreflang="af" data-title="Ashelling" data-language-autonym="Afrikaans" data-language-local-name="Afrikaans" class="interlanguage-link-target"><span>Afrikaans</span></a></li><li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D9%85%D9%8A%D9%84_%D9%85%D8%AD%D9%88%D8%B1%D9%8A" title="ميل محوري – Arabic" lang="ar" hreflang="ar" data-title="ميل محوري" data-language-autonym="العربية" data-language-local-name="Arabic" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-an mw-list-item"><a href="https://an.wikipedia.org/wiki/Inclinaci%C3%B3n_axial" title="Inclinación axial – Aragonese" lang="an" hreflang="an" data-title="Inclinación axial" data-language-autonym="Aragonés" data-language-local-name="Aragonese" class="interlanguage-link-target"><span>Aragonés</span></a></li><li class="interlanguage-link interwiki-ast mw-list-item"><a href="https://ast.wikipedia.org/wiki/Encl%C3%ADn_axal" title="Enclín axal – Asturian" lang="ast" hreflang="ast" data-title="Enclín axal" data-language-autonym="Asturianu" data-language-local-name="Asturian" class="interlanguage-link-target"><span>Asturianu</span></a></li><li class="interlanguage-link interwiki-az mw-list-item"><a href="https://az.wikipedia.org/wiki/Yer_oxu" title="Yer oxu – Azerbaijani" lang="az" hreflang="az" data-title="Yer oxu" data-language-autonym="Azərbaycanca" data-language-local-name="Azerbaijani" class="interlanguage-link-target"><span>Azərbaycanca</span></a></li><li class="interlanguage-link interwiki-bn mw-list-item"><a href="https://bn.wikipedia.org/wiki/%E0%A6%86%E0%A6%95%E0%A7%8D%E0%A6%B7%E0%A6%BF%E0%A6%95_%E0%A6%86%E0%A6%A8%E0%A6%A4%E0%A6%BF" title="আক্ষিক আনতি – Bangla" lang="bn" hreflang="bn" data-title="আক্ষিক আনতি" data-language-autonym="বাংলা" data-language-local-name="Bangla" class="interlanguage-link-target"><span>বাংলা</span></a></li><li class="interlanguage-link interwiki-be mw-list-item"><a href="https://be.wikipedia.org/wiki/%D0%9D%D0%B0%D1%85%D1%96%D0%BB_%D0%B2%D0%BE%D1%81%D1%96_%D0%B2%D1%8F%D1%80%D1%87%D1%8D%D0%BD%D0%BD%D1%8F" title="Нахіл восі вярчэння – Belarusian" lang="be" hreflang="be" data-title="Нахіл восі вярчэння" data-language-autonym="Беларуская" data-language-local-name="Belarusian" class="interlanguage-link-target"><span>Беларуская</span></a></li><li class="interlanguage-link interwiki-be-x-old mw-list-item"><a href="https://be-tarask.wikipedia.org/wiki/%D0%9D%D0%B0%D1%85%D1%96%D0%BB_%D0%B2%D0%BE%D1%81%D1%96_%D0%B2%D1%8F%D1%80%D1%87%D1%8D%D0%BD%D1%8C%D0%BD%D1%8F" title="Нахіл восі вярчэньня – Belarusian (Taraškievica orthography)" lang="be-tarask" hreflang="be-tarask" data-title="Нахіл восі вярчэньня" data-language-autonym="Беларуская (тарашкевіца)" data-language-local-name="Belarusian (Taraškievica orthography)" class="interlanguage-link-target"><span>Беларуская (тарашкевіца)</span></a></li><li class="interlanguage-link interwiki-bg mw-list-item"><a href="https://bg.wikipedia.org/wiki/%D0%9D%D0%B0%D0%BA%D0%BB%D0%BE%D0%BD_%D0%BD%D0%B0_%D0%BE%D1%81%D1%82%D0%B0_(%D0%B0%D1%81%D1%82%D1%80%D0%BE%D0%BD%D0%BE%D0%BC%D0%B8%D1%8F)" title="Наклон на оста (астрономия) – Bulgarian" lang="bg" hreflang="bg" data-title="Наклон на оста (астрономия)" data-language-autonym="Български" data-language-local-name="Bulgarian" class="interlanguage-link-target"><span>Български</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/Obliq%C3%BCitat_de_l%27ecl%C3%ADptica" title="Obliqüitat de l'eclíptica – Catalan" lang="ca" hreflang="ca" data-title="Obliqüitat de l'eclíptica" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-cv mw-list-item"><a href="https://cv.wikipedia.org/wiki/%D0%9F%D0%BB%D0%B0%D0%BD%D0%B5%D1%82%C4%83%D0%BD_%C3%A7%D0%B0%D0%B2%D1%80%C4%83%D0%BD%D1%83_%D1%82%C4%95%D0%BD%C4%95%D0%BB%C4%95%D0%BD_%D1%82%D0%B0%D0%B9%D0%BB%C4%83%D0%BC%C4%95" title="Планетăн çаврăну тĕнĕлĕн тайлăмĕ – Chuvash" lang="cv" hreflang="cv" data-title="Планетăн çаврăну тĕнĕлĕн тайлăмĕ" data-language-autonym="Чӑвашла" data-language-local-name="Chuvash" class="interlanguage-link-target"><span>Чӑвашла</span></a></li><li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/Sklon_rota%C4%8Dn%C3%AD_osy" title="Sklon rotační osy – Czech" lang="cs" hreflang="cs" data-title="Sklon rotační osy" data-language-autonym="Čeština" data-language-local-name="Czech" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-da mw-list-item"><a href="https://da.wikipedia.org/wiki/Akseh%C3%A6ldning" title="Aksehældning – Danish" lang="da" hreflang="da" data-title="Aksehældning" data-language-autonym="Dansk" data-language-local-name="Danish" class="interlanguage-link-target"><span>Dansk</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Achsneigung" title="Achsneigung – German" lang="de" hreflang="de" data-title="Achsneigung" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Oblicuidad_de_la_ecl%C3%ADptica" title="Oblicuidad de la eclíptica – Spanish" lang="es" hreflang="es" data-title="Oblicuidad de la eclíptica" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-eo mw-list-item"><a href="https://eo.wikipedia.org/wiki/Aksa_klini%C4%9Do" title="Aksa kliniĝo – Esperanto" lang="eo" hreflang="eo" data-title="Aksa kliniĝo" data-language-autonym="Esperanto" data-language-local-name="Esperanto" class="interlanguage-link-target"><span>Esperanto</span></a></li><li class="interlanguage-link interwiki-eu mw-list-item"><a href="https://eu.wikipedia.org/wiki/Makurdura_axial" title="Makurdura axial – Basque" lang="eu" hreflang="eu" data-title="Makurdura axial" data-language-autonym="Euskara" data-language-local-name="Basque" class="interlanguage-link-target"><span>Euskara</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%D8%A7%D9%86%D8%AD%D8%B1%D8%A7%D9%81_%D9%85%D8%AD%D9%88%D8%B1%DB%8C" title="انحراف محوری – Persian" lang="fa" hreflang="fa" data-title="انحراف محوری" data-language-autonym="فارسی" data-language-local-name="Persian" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Inclinaison_de_l%27axe" title="Inclinaison de l'axe – French" lang="fr" hreflang="fr" data-title="Inclinaison de l'axe" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-gl mw-list-item"><a href="https://gl.wikipedia.org/wiki/Oblicuidade_da_ecl%C3%ADptica" title="Oblicuidade da eclíptica – Galician" lang="gl" hreflang="gl" data-title="Oblicuidade da eclíptica" data-language-autonym="Galego" data-language-local-name="Galician" class="interlanguage-link-target"><span>Galego</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%EC%9E%90%EC%A0%84%EC%B6%95_%EA%B8%B0%EC%9A%B8%EA%B8%B0" title="자전축 기울기 – Korean" lang="ko" hreflang="ko" data-title="자전축 기울기" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-hi mw-list-item"><a href="https://hi.wikipedia.org/wiki/%E0%A4%85%E0%A4%95%E0%A5%8D%E0%A4%B7%E0%A5%80%E0%A4%AF_%E0%A4%9D%E0%A5%81%E0%A4%95%E0%A4%BE%E0%A4%B5" title="अक्षीय झुकाव – Hindi" lang="hi" hreflang="hi" data-title="अक्षीय झुकाव" data-language-autonym="हिन्दी" data-language-local-name="Hindi" class="interlanguage-link-target"><span>हिन्दी</span></a></li><li class="interlanguage-link interwiki-hr mw-list-item"><a href="https://hr.wikipedia.org/wiki/Nagib_osi" title="Nagib osi – Croatian" lang="hr" hreflang="hr" data-title="Nagib osi" data-language-autonym="Hrvatski" data-language-local-name="Croatian" class="interlanguage-link-target"><span>Hrvatski</span></a></li><li class="interlanguage-link interwiki-id mw-list-item"><a href="https://id.wikipedia.org/wiki/Kemiringan_sumbu" title="Kemiringan sumbu – Indonesian" lang="id" hreflang="id" data-title="Kemiringan sumbu" data-language-autonym="Bahasa Indonesia" data-language-local-name="Indonesian" class="interlanguage-link-target"><span>Bahasa Indonesia</span></a></li><li class="interlanguage-link interwiki-is mw-list-item"><a href="https://is.wikipedia.org/wiki/M%C3%B6ndulhalli" title="Möndulhalli – Icelandic" lang="is" hreflang="is" data-title="Möndulhalli" data-language-autonym="Íslenska" data-language-local-name="Icelandic" class="interlanguage-link-target"><span>Íslenska</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Inclinazione_assiale" title="Inclinazione assiale – Italian" lang="it" hreflang="it" data-title="Inclinazione assiale" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-he mw-list-item"><a href="https://he.wikipedia.org/wiki/%D7%A0%D7%98%D7%99%D7%99%D7%AA_%D7%A6%D7%99%D7%A8_%D7%94%D7%A1%D7%99%D7%91%D7%95%D7%91" title="נטיית ציר הסיבוב – Hebrew" lang="he" hreflang="he" data-title="נטיית ציר הסיבוב" data-language-autonym="עברית" data-language-local-name="Hebrew" class="interlanguage-link-target"><span>עברית</span></a></li><li class="interlanguage-link interwiki-ht mw-list-item"><a href="https://ht.wikipedia.org/wiki/Aks_(jewografi)" title="Aks (jewografi) – Haitian Creole" lang="ht" hreflang="ht" data-title="Aks (jewografi)" data-language-autonym="Kreyòl ayisyen" data-language-local-name="Haitian Creole" class="interlanguage-link-target"><span>Kreyòl ayisyen</span></a></li><li class="interlanguage-link interwiki-ky mw-list-item"><a href="https://ky.wikipedia.org/wiki/%D0%90%D0%B9%D0%BB%D0%B0%D0%BD%D1%83%D1%83_%D0%BE%D0%B3%D1%83%D0%BD%D1%83%D0%BD_%D0%B6%D0%B0%D0%BD%D1%82%D0%B0%D0%B9%D1%8B%D1%88%D1%8B" title="Айлануу огунун жантайышы – Kyrgyz" lang="ky" hreflang="ky" data-title="Айлануу огунун жантайышы" data-language-autonym="Кыргызча" data-language-local-name="Kyrgyz" class="interlanguage-link-target"><span>Кыргызча</span></a></li><li class="interlanguage-link interwiki-lv mw-list-item"><a href="https://lv.wikipedia.org/wiki/Ass_sl%C4%ABpums" title="Ass slīpums – Latvian" lang="lv" hreflang="lv" data-title="Ass slīpums" data-language-autonym="Latviešu" data-language-local-name="Latvian" class="interlanguage-link-target"><span>Latviešu</span></a></li><li class="interlanguage-link interwiki-lb mw-list-item"><a href="https://lb.wikipedia.org/wiki/Inklinatioun_(Astronomie)" title="Inklinatioun (Astronomie) – Luxembourgish" lang="lb" hreflang="lb" data-title="Inklinatioun (Astronomie)" data-language-autonym="Lëtzebuergesch" data-language-local-name="Luxembourgish" class="interlanguage-link-target"><span>Lëtzebuergesch</span></a></li><li class="interlanguage-link interwiki-lt mw-list-item"><a href="https://lt.wikipedia.org/wiki/A%C5%A1ies_posvyris" title="Ašies posvyris – Lithuanian" lang="lt" hreflang="lt" data-title="Ašies posvyris" data-language-autonym="Lietuvių" data-language-local-name="Lithuanian" class="interlanguage-link-target"><span>Lietuvių</span></a></li><li class="interlanguage-link interwiki-hu mw-list-item"><a href="https://hu.wikipedia.org/wiki/Tengelyferdes%C3%A9g" title="Tengelyferdeség – Hungarian" lang="hu" hreflang="hu" data-title="Tengelyferdeség" data-language-autonym="Magyar" data-language-local-name="Hungarian" class="interlanguage-link-target"><span>Magyar</span></a></li><li class="interlanguage-link interwiki-mk mw-list-item"><a href="https://mk.wikipedia.org/wiki/%D0%9E%D1%81%D0%B5%D0%BD_%D0%BD%D0%B0%D0%BA%D0%BB%D0%BE%D0%BD" title="Осен наклон – Macedonian" lang="mk" hreflang="mk" data-title="Осен наклон" data-language-autonym="Македонски" data-language-local-name="Macedonian" class="interlanguage-link-target"><span>Македонски</span></a></li><li class="interlanguage-link interwiki-mr mw-list-item"><a href="https://mr.wikipedia.org/wiki/%E0%A4%86%E0%A4%B8%E0%A4%BE%E0%A4%9A%E0%A4%BE_%E0%A4%95%E0%A4%B2" title="आसाचा कल – Marathi" lang="mr" hreflang="mr" data-title="आसाचा कल" data-language-autonym="मराठी" data-language-local-name="Marathi" class="interlanguage-link-target"><span>मराठी</span></a></li><li class="interlanguage-link interwiki-ms mw-list-item"><a href="https://ms.wikipedia.org/wiki/Kecondongan_paksi" title="Kecondongan paksi – Malay" lang="ms" hreflang="ms" data-title="Kecondongan paksi" data-language-autonym="Bahasa Melayu" data-language-local-name="Malay" class="interlanguage-link-target"><span>Bahasa Melayu</span></a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/Obliquiteit" title="Obliquiteit – Dutch" lang="nl" hreflang="nl" data-title="Obliquiteit" data-language-autonym="Nederlands" data-language-local-name="Dutch" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/%E8%B5%A4%E9%81%93%E5%82%BE%E6%96%9C%E8%A7%92" title="赤道傾斜角 – Japanese" lang="ja" hreflang="ja" data-title="赤道傾斜角" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-no mw-list-item"><a href="https://no.wikipedia.org/wiki/Aksehelning" title="Aksehelning – Norwegian Bokmål" lang="nb" hreflang="nb" data-title="Aksehelning" data-language-autonym="Norsk bokmål" data-language-local-name="Norwegian Bokmål" class="interlanguage-link-target"><span>Norsk bokmål</span></a></li><li class="interlanguage-link interwiki-nn mw-list-item"><a href="https://nn.wikipedia.org/wiki/Aksehelling" title="Aksehelling – Norwegian Nynorsk" lang="nn" hreflang="nn" data-title="Aksehelling" data-language-autonym="Norsk nynorsk" data-language-local-name="Norwegian Nynorsk" class="interlanguage-link-target"><span>Norsk nynorsk</span></a></li><li class="interlanguage-link interwiki-pa mw-list-item"><a href="https://pa.wikipedia.org/wiki/%E0%A8%A7%E0%A8%B0%E0%A9%82%E0%A8%B5%E0%A9%80_%E0%A8%9D%E0%A9%81%E0%A8%95%E0%A8%BE%E0%A8%85" title="ਧਰੂਵੀ ਝੁਕਾਅ – Punjabi" lang="pa" hreflang="pa" data-title="ਧਰੂਵੀ ਝੁਕਾਅ" data-language-autonym="ਪੰਜਾਬੀ" data-language-local-name="Punjabi" class="interlanguage-link-target"><span>ਪੰਜਾਬੀ</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/Inclina%C3%A7%C3%A3o_axial" title="Inclinação axial – Portuguese" lang="pt" hreflang="pt" data-title="Inclinação axial" data-language-autonym="Português" data-language-local-name="Portuguese" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-ro mw-list-item"><a href="https://ro.wikipedia.org/wiki/%C3%8Enclinare_axial%C4%83" title="Înclinare axială – Romanian" lang="ro" hreflang="ro" data-title="Înclinare axială" data-language-autonym="Română" data-language-local-name="Romanian" class="interlanguage-link-target"><span>Română</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/%D0%9D%D0%B0%D0%BA%D0%BB%D0%BE%D0%BD_%D0%BE%D1%81%D0%B8_%D0%B2%D1%80%D0%B0%D1%89%D0%B5%D0%BD%D0%B8%D1%8F" title="Наклон оси вращения – Russian" lang="ru" hreflang="ru" data-title="Наклон оси вращения" data-language-autonym="Русский" data-language-local-name="Russian" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-simple mw-list-item"><a href="https://simple.wikipedia.org/wiki/Axial_tilt" title="Axial tilt – Simple English" lang="en-simple" hreflang="en-simple" data-title="Axial tilt" data-language-autonym="Simple English" data-language-local-name="Simple English" class="interlanguage-link-target"><span>Simple English</span></a></li><li class="interlanguage-link interwiki-sk mw-list-item"><a href="https://sk.wikipedia.org/wiki/Sklon_osi_rot%C3%A1cie" title="Sklon osi rotácie – Slovak" lang="sk" hreflang="sk" data-title="Sklon osi rotácie" data-language-autonym="Slovenčina" data-language-local-name="Slovak" class="interlanguage-link-target"><span>Slovenčina</span></a></li><li class="interlanguage-link interwiki-sl mw-list-item"><a href="https://sl.wikipedia.org/wiki/Nagib_vrtilne_osi" title="Nagib vrtilne osi – Slovenian" lang="sl" hreflang="sl" data-title="Nagib vrtilne osi" 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class="noprint">From Wikipedia, the free encyclopedia</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="en" dir="ltr"><style data-mw-deduplicate="TemplateStyles:r1236090951">.mw-parser-output .hatnote{font-style:italic}.mw-parser-output div.hatnote{padding-left:1.6em;margin-bottom:0.5em}.mw-parser-output .hatnote i{font-style:normal}.mw-parser-output .hatnote+link+.hatnote{margin-top:-0.5em}@media print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">"Obliquity" redirects here. For the book, see <a href="/wiki/Obliquity_(book)" title="Obliquity (book)">Obliquity (book)</a>.</div> <div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none">Angle between the rotational axis and orbital axis of a body</div> <figure typeof="mw:File/Thumb"><a href="/wiki/File:Planet_axis_comparison.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/2/29/Planet_axis_comparison.png/380px-Planet_axis_comparison.png" decoding="async" width="380" height="216" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/2/29/Planet_axis_comparison.png/570px-Planet_axis_comparison.png 1.5x, //upload.wikimedia.org/wikipedia/commons/2/29/Planet_axis_comparison.png 2x" data-file-width="706" data-file-height="402" /></a><figcaption>The <b>positive</b> pole of a planet is defined by the <a href="/wiki/Right-hand_rule" title="Right-hand rule">right-hand rule</a>: if the fingers of the right hand are curled in the direction of the rotation then the thumb points to the positive pole. The axial tilt is defined as the angle between the direction of the positive pole and the normal to the orbital plane. The angles for Earth, Uranus, and Venus are approximately 23°, 97°, and 177° respectively.</figcaption></figure><p>In <a href="/wiki/Astronomy" title="Astronomy">astronomy</a>, <b>axial tilt</b>, also known as <b>obliquity</b>, is the <a href="/wiki/Angle" title="Angle">angle</a> between an object's <a href="/wiki/Rotation_around_a_fixed_axis" title="Rotation around a fixed axis">rotational axis</a> and its <a href="/wiki/Orbit" title="Orbit">orbital</a> axis, which is the line <a href="/wiki/Perpendicular" title="Perpendicular">perpendicular</a> to its <a href="/wiki/Orbital_plane_(astronomy)" class="mw-redirect" title="Orbital plane (astronomy)">orbital plane</a>; equivalently, it is the angle between its <a href="/wiki/Equator" title="Equator">equatorial</a> plane and orbital plane.<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> It differs from <a href="/wiki/Orbital_inclination" title="Orbital inclination">orbital inclination</a>. </p><p>At an obliquity of 0 degrees, the two axes point in the same direction; that is, the rotational axis is perpendicular to the orbital plane. </p><p>The rotational axis of <a href="/wiki/Earth" title="Earth">Earth</a>, for example, is the imaginary line that passes through both the <a href="/wiki/North_Pole" title="North Pole">North Pole</a> and <a href="/wiki/South_Pole" title="South Pole">South Pole</a>, whereas the Earth's orbital axis is the line perpendicular to the imaginary <a href="/wiki/Plane_(geometry)" class="mw-redirect" title="Plane (geometry)">plane</a> through which the Earth moves as it revolves around the <a href="/wiki/Sun" title="Sun">Sun</a>; the Earth's obliquity or axial tilt is the angle between these two lines. </p><p>Over the course of an <a href="/wiki/Orbital_period" title="Orbital period">orbital period</a>, the obliquity usually does not change considerably, and the <a href="/wiki/Axial_parallelism" title="Axial parallelism">orientation of the axis remains the same</a> relative to the <a href="/wiki/Celestial_sphere" title="Celestial sphere">background</a> of <a href="/wiki/Fixed_stars" title="Fixed stars">stars</a>. This causes one pole to be pointed more toward the Sun on one side of the orbit, and more away from the Sun on the other side—the cause of the <a href="/wiki/Season" title="Season">seasons</a> on Earth. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Standards">Standards</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Axial_tilt&action=edit&section=1" title="Edit section: Standards"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>There are two standard methods of specifying a planet's tilt. One way is based on the planet's <i>north pole</i>, defined in relation to the direction of Earth's north pole, and the other way is based on the planet's <i>positive pole</i>, defined by the <a href="/wiki/Axis%E2%80%93angle_representation" title="Axis–angle representation">right-hand rule</a>: </p> <ul><li>The <a href="/wiki/International_Astronomical_Union" title="International Astronomical Union">International Astronomical Union</a> (IAU) defines the <i>north pole</i> of a planet as that which lies on Earth's north side of the <a href="/wiki/Invariable_plane" title="Invariable plane">invariable plane</a> of the <a href="/wiki/Solar_System" title="Solar System">Solar System</a>;<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> under this system, <a href="/wiki/Venus" title="Venus">Venus</a> is tilted 3° and rotates <a href="/wiki/Retrograde_motion" class="mw-redirect" title="Retrograde motion">retrograde</a>, opposite that of most of the other planets.<sup id="cite_ref-CorreiaVenusI_3-0" class="reference"><a href="#cite_note-CorreiaVenusI-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup></li> <li>The IAU also uses the right-hand rule to define a <i>positive pole</i><sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> for the purpose of determining orientation. Using this convention, Venus is tilted 177° ("upside down") and rotates prograde.</li></ul> <div class="mw-heading mw-heading2"><h2 id="Earth">Earth</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Axial_tilt&action=edit&section=2" title="Edit section: Earth"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Further information: <a href="/wiki/Ecliptic#Obliquity_of_the_ecliptic" title="Ecliptic">Ecliptic § Obliquity of the ecliptic</a></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/Earth%27s_rotation" title="Earth's rotation">Earth's rotation</a> and <a href="/wiki/Earth-centered_inertial" title="Earth-centered inertial">Earth-centered inertial</a></div> <p><a href="/wiki/Earth" title="Earth">Earth</a>'s <a href="/wiki/Orbit" title="Orbit">orbital plane</a> is known as the <a href="/wiki/Ecliptic" title="Ecliptic">ecliptic</a> plane, and <a href="/wiki/Earth#Axial_tilt_and_seasons" title="Earth">Earth's tilt</a> is known to astronomers as the <i>obliquity of the ecliptic</i>, being the angle between the ecliptic and the <a href="/wiki/Celestial_equator" title="Celestial equator">celestial equator</a> on the <a href="/wiki/Celestial_sphere" title="Celestial sphere">celestial sphere</a>.<sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> It is denoted by the <a href="/wiki/Greek_letter" class="mw-redirect" title="Greek letter">Greek letter</a> Epsilon <i><a href="/wiki/Epsilon" title="Epsilon">ε</a></i>. </p><p>Earth currently has an axial tilt of about 23.44°.<sup id="cite_ref-7" class="reference"><a href="#cite_note-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> This value remains about the same relative to a stationary orbital plane throughout the cycles of <a href="/wiki/Axial_precession" title="Axial precession">axial precession</a>.<sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> But the ecliptic (i.e., Earth's orbit) moves due to planetary <a href="/wiki/Perturbation_(astronomy)" title="Perturbation (astronomy)">perturbations</a>, and the obliquity of the ecliptic is not a fixed quantity. At present, it is decreasing at a rate of about <a href="/wiki/Second_of_arc" class="mw-redirect" title="Second of arc">46.8″</a><sup id="cite_ref-Ray2014_9-0" class="reference"><a href="#cite_note-Ray2014-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> per <a href="/wiki/Century" title="Century">century</a> <i>(see details in <a href="#Short_term">Short term</a> below)</i>. </p> <div class="mw-heading mw-heading3"><h3 id="History">History</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Axial_tilt&action=edit&section=3" title="Edit section: History"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The ancient Greeks had good measurements of the obliquity since about 350 BCE, when <a href="/wiki/Pytheas" title="Pytheas">Pytheas</a> of Marseilles measured the shadow of a <a href="/wiki/Gnomon" title="Gnomon">gnomon</a> at the summer solstice.<sup id="cite_ref-10" class="reference"><a href="#cite_note-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> About 830 CE, the Caliph <a href="/wiki/Al-Mamun" class="mw-redirect" title="Al-Mamun">Al-Mamun</a> of Baghdad directed his astronomers to measure the obliquity, and the result was used in the Arab world for many years.<sup id="cite_ref-11" class="reference"><a href="#cite_note-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> In 1437, <a href="/wiki/Ulugh_Beg" title="Ulugh Beg">Ulugh Beg</a> determined the Earth's axial tilt as 23°30′17″ (23.5047°).<sup id="cite_ref-12" class="reference"><a href="#cite_note-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup> </p><p>During the <a href="/wiki/Middle_Ages" title="Middle Ages">Middle Ages</a>, it was widely believed that both precession and Earth's obliquity oscillated around a mean value, with a period of 672 years, an idea known as <i><a href="/wiki/Trepidation_(astronomy)" class="mw-redirect" title="Trepidation (astronomy)">trepidation</a></i> of the equinoxes. Perhaps the first to realize this was incorrect (during historic time) was <a href="/wiki/Ibn_al-Shatir" title="Ibn al-Shatir">Ibn al-Shatir</a> in the fourteenth century<sup id="cite_ref-13" class="reference"><a href="#cite_note-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup> and the first to realize that the obliquity is decreasing at a relatively constant rate was <a href="/wiki/Fracastoro" class="mw-redirect" title="Fracastoro">Fracastoro</a> in 1538.<sup id="cite_ref-14" class="reference"><a href="#cite_note-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup> The first accurate, modern, western observations of the obliquity were probably those of <a href="/wiki/Tycho_Brahe" title="Tycho Brahe">Tycho Brahe</a> from <a href="/wiki/Denmark" title="Denmark">Denmark</a>, about 1584,<sup id="cite_ref-15" class="reference"><a href="#cite_note-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup> although observations by several others, including <a href="/wiki/Al-Ma%27mun" title="Al-Ma'mun">al-Ma'mun</a>, <a href="/wiki/Sharaf_al-D%C4%ABn_al-T%C5%ABs%C4%AB" class="mw-redirect" title="Sharaf al-Dīn al-Tūsī">al-Tusi</a>,<sup id="cite_ref-16" class="reference"><a href="#cite_note-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup> <a href="/wiki/Georg_Purbach" class="mw-redirect" title="Georg Purbach">Purbach</a>, <a href="/wiki/Regiomontanus" title="Regiomontanus">Regiomontanus</a>, and <a href="/wiki/Bernhard_Walther" title="Bernhard Walther">Walther</a>, could have provided similar information. </p> <div class="mw-heading mw-heading3"><h3 id="Seasons">Seasons</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Axial_tilt&action=edit&section=4" title="Edit section: Seasons"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Season" title="Season">Season</a></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Earth_tilt_animation.gif" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/5/58/Earth_tilt_animation.gif/220px-Earth_tilt_animation.gif" decoding="async" width="220" height="111" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/5/58/Earth_tilt_animation.gif/330px-Earth_tilt_animation.gif 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/5/58/Earth_tilt_animation.gif/440px-Earth_tilt_animation.gif 2x" data-file-width="774" data-file-height="392" /></a><figcaption>The axis of Earth remains oriented in the same direction with reference to the background stars regardless of where it is in its <a href="/wiki/Earth%27s_orbit" title="Earth's orbit">orbit</a>. Northern hemisphere summer occurs at the right side of this diagram, where the north pole (red) is directed toward the Sun, winter at the left.</figcaption></figure> <p><a href="/wiki/Earth" title="Earth">Earth</a>'s axis remains tilted in the same direction with reference to the background stars throughout a year (regardless of where it is in its <a href="/wiki/Orbit" title="Orbit">orbit</a>) due to the <a href="/wiki/Gyroscope" title="Gyroscope">gyroscope effect</a>. This means that one pole (and the associated <a href="/wiki/Hemispheres_of_the_Earth" class="mw-redirect" title="Hemispheres of the Earth">hemisphere of Earth</a>) will be directed away from the Sun at one side of the orbit, and half an orbit later (half a year later) this pole will be directed towards the Sun. This is the cause of Earth's <a href="/wiki/Season" title="Season">seasons</a>. <a href="/wiki/Summer" title="Summer">Summer</a> occurs in the <a href="/wiki/Northern_hemisphere" class="mw-redirect" title="Northern hemisphere">Northern hemisphere</a> when the north pole is directed toward the Sun. Variations in Earth's axial tilt can influence the seasons and is likely a factor in long-term <a href="/wiki/Climate_change_(general_concept)" class="mw-redirect" title="Climate change (general concept)">climatic change</a> <i>(also see <a href="/wiki/Milankovitch_cycles" title="Milankovitch cycles">Milankovitch cycles</a>)</i>. </p> <figure class="mw-halign-center" typeof="mw:File/Thumb"><a href="/wiki/File:Axial_tilt_vs_tropical_and_polar_circles.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/4/40/Axial_tilt_vs_tropical_and_polar_circles.svg/420px-Axial_tilt_vs_tropical_and_polar_circles.svg.png" decoding="async" width="420" height="153" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/4/40/Axial_tilt_vs_tropical_and_polar_circles.svg/630px-Axial_tilt_vs_tropical_and_polar_circles.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/4/40/Axial_tilt_vs_tropical_and_polar_circles.svg/840px-Axial_tilt_vs_tropical_and_polar_circles.svg.png 2x" data-file-width="512" data-file-height="186" /></a><figcaption>Relationship between Earth's axial tilt (ε) to the tropical and polar circles</figcaption></figure> <div class="mw-heading mw-heading3"><h3 id="Oscillation">Oscillation</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Axial_tilt&action=edit&section=5" title="Edit section: Oscillation"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading4"><h4 id="Short_term">Short term</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Axial_tilt&action=edit&section=6" title="Edit section: Short term"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Obliquity_of_the_ecliptic_laskar.PNG" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/1/14/Obliquity_of_the_ecliptic_laskar.PNG/220px-Obliquity_of_the_ecliptic_laskar.PNG" decoding="async" width="220" height="149" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/14/Obliquity_of_the_ecliptic_laskar.PNG/330px-Obliquity_of_the_ecliptic_laskar.PNG 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/14/Obliquity_of_the_ecliptic_laskar.PNG/440px-Obliquity_of_the_ecliptic_laskar.PNG 2x" data-file-width="1221" data-file-height="826" /></a><figcaption>Obliquity of the ecliptic for 20,000 years, from <a href="/wiki/Jacques_Laskar" title="Jacques Laskar">Laskar</a> (1986). The red point represents the year 2000.</figcaption></figure> <p>The exact angular value of the obliquity is found by observation of the motions of Earth and <a href="/wiki/Planets" class="mw-redirect" title="Planets">planets</a> over many years. Astronomers produce new <a href="/wiki/Fundamental_ephemeris" title="Fundamental ephemeris">fundamental ephemerides</a> as the accuracy of <a href="/wiki/Observational_astronomy" title="Observational astronomy">observation</a> improves and as the understanding of the <a href="/wiki/Analytical_dynamics" class="mw-redirect" title="Analytical dynamics">dynamics</a> increases, and from these ephemerides various astronomical values, including the obliquity, are derived. </p><p>Annual <a href="/wiki/Almanac" title="Almanac">almanacs</a> are published listing the derived values and methods of use. Until 1983, the <a href="/wiki/Astronomical_Almanac" title="Astronomical Almanac">Astronomical Almanac</a>'s angular value of the mean obliquity for any date was calculated based on the <a href="/wiki/Newcomb%27s_Tables_of_the_Sun" title="Newcomb's Tables of the Sun">work of Newcomb</a>, who analyzed positions of the planets until about 1895: </p> <dl><dd><span class="texhtml"><i>ε</i> = 23°27′8.26″ − 46.845″ <i>T</i> − 0.0059″ <i>T</i><sup>2</sup> + <span class="nowrap"><span data-sort-value="6997181000000000000♠"></span>0.001<span style="margin-left:.25em;">81</span></span>″ <i>T</i><sup>3</sup></span></dd></dl> <p>where <span class="texhtml"><i>ε</i></span> is the obliquity and <span class="texhtml"><i>T</i></span> is <a href="/wiki/Tropical_year" title="Tropical year">tropical centuries</a> from <a href="/wiki/Epoch_(astronomy)#Besselian_years" title="Epoch (astronomy)">B1900.0</a> to the date in question.<sup id="cite_ref-17" class="reference"><a href="#cite_note-17"><span class="cite-bracket">[</span>17<span class="cite-bracket">]</span></a></sup> </p><p>From 1984, the <a href="/wiki/Jet_Propulsion_Laboratory_Development_Ephemeris" title="Jet Propulsion Laboratory Development Ephemeris">Jet Propulsion Laboratory's DE series</a> of computer-generated ephemerides took over as the <a href="/wiki/Fundamental_ephemeris" title="Fundamental ephemeris">fundamental ephemeris</a> of the <a href="/wiki/Astronomical_Almanac" title="Astronomical Almanac">Astronomical Almanac</a>. Obliquity based on DE200, which analyzed observations from 1911 to 1979, was calculated: </p> <dl><dd><span class="texhtml"><i>ε</i> = 23°26′21.448″ − 46.8150″ <i>T</i> − 0.00059″ <i>T</i><sup>2</sup> + <span class="nowrap"><span data-sort-value="6997181300000000000♠"></span>0.001<span style="margin-left:.25em;">813</span></span>″ <i>T</i><sup>3</sup></span></dd></dl> <p>where hereafter <span class="texhtml"><i>T</i></span> is <a href="/wiki/Julian_year_(astronomy)" title="Julian year (astronomy)">Julian centuries</a> from <a href="/wiki/Epoch_(astronomy)#Julian_years_and_J2000" title="Epoch (astronomy)">J2000.0</a>.<sup id="cite_ref-18" class="reference"><a href="#cite_note-18"><span class="cite-bracket">[</span>18<span class="cite-bracket">]</span></a></sup> </p><p>JPL's fundamental ephemerides have been continually updated. For instance, according to IAU resolution in 2006 in favor of the P03 astronomical model, the <i>Astronomical Almanac</i> for 2010 specifies:<sup id="cite_ref-ReferenceA_19-0" class="reference"><a href="#cite_note-ReferenceA-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup> </p> <dl><dd><span class="texhtml"><i>ε</i> = 23°26′21.406″ − <span class="nowrap"><span data-sort-value="7001468367689999999♠"></span>46.836<span style="margin-left:.25em;">769</span></span>″ <i>T</i> − <span class="nowrap"><span data-sort-value="6996183100000000000♠"></span>0.000<span style="margin-left:.25em;">1831</span></span>″ <i>T</i><sup>2</sup> + <span class="nowrap"><span data-sort-value="6997200339999999999♠"></span>0.002<span style="margin-left:.25em;">003</span><span style="margin-left:.25em;">40</span></span>″ <i>T</i><sup>3</sup> − 5.76″ × 10<sup>−7</sup> <i>T</i><sup>4</sup> − 4.34″ × 10<sup>−8</sup> <i>T</i><sup>5</sup></span></dd></dl> <p>These expressions for the obliquity are intended for high precision over a relatively short time span, perhaps <span class="texhtml">±</span> several centuries.<sup id="cite_ref-20" class="reference"><a href="#cite_note-20"><span class="cite-bracket">[</span>20<span class="cite-bracket">]</span></a></sup> <a href="/wiki/Jacques_Laskar" title="Jacques Laskar">Jacques Laskar</a> computed an expression to order <span class="texhtml"><i>T</i><sup>10</sup></span> good to 0.02″ over 1000 years and several <a href="/wiki/Minute_of_arc" class="mw-redirect" title="Minute of arc">arcseconds</a> over 10,000 years. </p> <dl><dd><span class="texhtml"><i>ε</i> = 23°26′21.448″ − 4680.93″ <i>t</i> − 1.55″ <i>t</i><sup>2</sup> + 1999.25″ <i>t</i><sup>3</sup> − 51.38″ <i>t</i><sup>4</sup> − 249.67″ <i>t</i><sup>5</sup> − 39.05″ <i>t</i><sup>6</sup> + 7.12″ <i>t</i><sup>7</sup> + 27.87″ <i>t</i><sup>8</sup> + 5.79″ <i>t</i><sup>9</sup> + 2.45″ <i>t</i><sup>10</sup></span></dd></dl> <p>where here <span class="texhtml"><i>t</i></span> is multiples of 10,000 <a href="/wiki/Julian_day" title="Julian day">Julian years</a> from <a href="/wiki/Epoch_(astronomy)#Julian_years_and_J2000" title="Epoch (astronomy)">J2000.0</a>.<sup id="cite_ref-laskar_21-0" class="reference"><a href="#cite_note-laskar-21"><span class="cite-bracket">[</span>21<span class="cite-bracket">]</span></a></sup> </p><p>These expressions are for the so-called <i>mean</i> obliquity, that is, the obliquity free from short-term variations. Periodic motions of the Moon and of Earth in its orbit cause much smaller (9.2 <a href="/wiki/Minute_of_arc" class="mw-redirect" title="Minute of arc">arcseconds</a>) short-period (about 18.6 years) oscillations of the rotation axis of Earth, known as <a href="/wiki/Astronomical_nutation" title="Astronomical nutation">nutation</a>, which add a periodic component to Earth's obliquity.<sup id="cite_ref-22" class="reference"><a href="#cite_note-22"><span class="cite-bracket">[</span>22<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-23" class="reference"><a href="#cite_note-23"><span class="cite-bracket">[</span>23<span class="cite-bracket">]</span></a></sup> The <i>true</i> or instantaneous obliquity includes this nutation.<sup id="cite_ref-24" class="reference"><a href="#cite_note-24"><span class="cite-bracket">[</span>24<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading4"><h4 id="Long_term">Long term</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Axial_tilt&action=edit&section=7" title="Edit section: Long term"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Formation_and_evolution_of_the_Solar_System" title="Formation and evolution of the Solar System">Formation and evolution of the Solar System</a></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Milankovitch_cycles" title="Milankovitch cycles">Milankovitch cycles</a></div> <p>Using <a href="/wiki/Numerical_methods" class="mw-redirect" title="Numerical methods">numerical methods</a> to simulate <a href="/wiki/Solar_System" title="Solar System">Solar System</a> behavior over a period of several million years, long-term changes in Earth's <a href="/wiki/Orbit" title="Orbit">orbit</a>, and hence its obliquity, have been investigated. For the past 5 million years, Earth's obliquity has varied between <span class="nowrap">22°2′33″</span> and <span class="nowrap">24°30′16″</span>, with a mean period of 41,040 years. This cycle is a combination of precession and the largest <a href="/wiki/Addend" class="mw-redirect" title="Addend">term</a> in the motion of the <a href="/wiki/Ecliptic" title="Ecliptic">ecliptic</a>. For the next 1 million years, the cycle will carry the obliquity between <span class="nowrap">22°13′44″</span> and <span class="nowrap">24°20′50″</span>.<sup id="cite_ref-25" class="reference"><a href="#cite_note-25"><span class="cite-bracket">[</span>25<span class="cite-bracket">]</span></a></sup> </p><p>The <a href="/wiki/Moon" title="Moon">Moon</a> has a stabilizing effect on Earth's obliquity. Frequency map analysis conducted in 1993 suggested that, in the absence of the Moon, the obliquity could change rapidly due to <a href="/wiki/Orbital_resonance" title="Orbital resonance">orbital resonances</a> and <a href="/wiki/Stability_of_the_Solar_System" title="Stability of the Solar System">chaotic behavior of the Solar System</a>, reaching as high as 90° in as little as a few million years (<i>also see <a href="/wiki/Orbit_of_the_Moon" title="Orbit of the Moon">Orbit of the Moon</a></i>).<sup id="cite_ref-LaskarRobutel_26-0" class="reference"><a href="#cite_note-LaskarRobutel-26"><span class="cite-bracket">[</span>26<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-27" class="reference"><a href="#cite_note-27"><span class="cite-bracket">[</span>27<span class="cite-bracket">]</span></a></sup> However, more recent numerical simulations<sup id="cite_ref-28" class="reference"><a href="#cite_note-28"><span class="cite-bracket">[</span>28<span class="cite-bracket">]</span></a></sup> made in 2011 indicated that even in the absence of the Moon, Earth's obliquity might not be quite so unstable; varying only by about 20–25°. To resolve this contradiction, diffusion rate of obliquity has been calculated, and it was found that it takes more than billions of years for Earth's obliquity to reach near 90°.<sup id="cite_ref-29" class="reference"><a href="#cite_note-29"><span class="cite-bracket">[</span>29<span class="cite-bracket">]</span></a></sup> The Moon's stabilizing effect will continue for less than two billion years. As the Moon continues to recede from Earth due to <a href="/wiki/Tidal_acceleration" title="Tidal acceleration">tidal acceleration</a>, resonances may occur which will cause large oscillations of the obliquity.<sup id="cite_ref-30" class="reference"><a href="#cite_note-30"><span class="cite-bracket">[</span>30<span class="cite-bracket">]</span></a></sup> </p> <style data-mw-deduplicate="TemplateStyles:r1237032888/mw-parser-output/.tmulti">.mw-parser-output .tmulti .multiimageinner{display:flex;flex-direction:column}.mw-parser-output .tmulti .trow{display:flex;flex-direction:row;clear:left;flex-wrap:wrap;width:100%;box-sizing:border-box}.mw-parser-output .tmulti .tsingle{margin:1px;float:left}.mw-parser-output .tmulti .theader{clear:both;font-weight:bold;text-align:center;align-self:center;background-color:transparent;width:100%}.mw-parser-output .tmulti .thumbcaption{background-color:transparent}.mw-parser-output .tmulti .text-align-left{text-align:left}.mw-parser-output .tmulti .text-align-right{text-align:right}.mw-parser-output .tmulti .text-align-center{text-align:center}@media all and (max-width:720px){.mw-parser-output .tmulti .thumbinner{width:100%!important;box-sizing:border-box;max-width:none!important;align-items:center}.mw-parser-output .tmulti .trow{justify-content:center}.mw-parser-output .tmulti .tsingle{float:none!important;max-width:100%!important;box-sizing:border-box;text-align:center}.mw-parser-output .tmulti .tsingle .thumbcaption{text-align:left}.mw-parser-output .tmulti .trow>.thumbcaption{text-align:center}}@media screen{html.skin-theme-clientpref-night .mw-parser-output .tmulti .multiimageinner img{background-color:white}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .tmulti .multiimageinner img{background-color:white}}</style><div class="thumb tmulti tnone center"><div class="thumbinner multiimageinner" style="width:544px;max-width:544px"><div class="trow"><div class="tsingle" style="width:266px;max-width:266px"><div class="thumbimage"><span typeof="mw:File"><a href="/wiki/File:Obliquity_berger_-5000000_to_0.png" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/1/12/Obliquity_berger_-5000000_to_0.png/264px-Obliquity_berger_-5000000_to_0.png" decoding="async" width="264" height="184" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/12/Obliquity_berger_-5000000_to_0.png/396px-Obliquity_berger_-5000000_to_0.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/12/Obliquity_berger_-5000000_to_0.png/528px-Obliquity_berger_-5000000_to_0.png 2x" data-file-width="1175" data-file-height="819" /></a></span></div></div><div class="tsingle" style="width:274px;max-width:274px"><div class="thumbimage"><span typeof="mw:File"><a href="/wiki/File:Obliquity_berger_0_to_1000000.png" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/1/17/Obliquity_berger_0_to_1000000.png/272px-Obliquity_berger_0_to_1000000.png" decoding="async" width="272" height="184" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/17/Obliquity_berger_0_to_1000000.png/408px-Obliquity_berger_0_to_1000000.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/17/Obliquity_berger_0_to_1000000.png/544px-Obliquity_berger_0_to_1000000.png 2x" data-file-width="1194" data-file-height="808" /></a></span></div></div></div><div class="trow" style="display:flex"><div class="thumbcaption">Long-term obliquity of the ecliptic. Left: for the past 5 million years; the obliquity varies only from about 22.0° to 24.5°. Right: for the next 1 million years; note the approx. 41,000-year period of variation. In both graphs, the red point represents the year 1850.<sup id="cite_ref-31" class="reference"><a href="#cite_note-31"><span class="cite-bracket">[</span>31<span class="cite-bracket">]</span></a></sup></div></div></div></div> <div class="mw-heading mw-heading2"><h2 id="Solar_System_bodies">Solar System bodies</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Axial_tilt&action=edit&section=8" title="Edit section: Solar System bodies"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/Poles_of_astronomical_bodies#Poles_of_rotation" title="Poles of astronomical bodies">Poles of astronomical bodies § Poles of rotation</a></div><figure class="mw-default-size" typeof="mw:File/Thumb"><span><video id="mwe_player_0" poster="//upload.wikimedia.org/wikipedia/commons/thumb/a/a1/Planets_and_dwarf_planets%27_tilt_and_rotation_speed.webm/330px--Planets_and_dwarf_planets%27_tilt_and_rotation_speed.webm.jpg" controls="" preload="none" data-mw-tmh="" class="mw-file-element" width="330" height="186" data-durationhint="80" data-mwtitle="Planets_and_dwarf_planets'_tilt_and_rotation_speed.webm" data-mwprovider="wikimediacommons" resource="/wiki/File:Planets_and_dwarf_planets%27_tilt_and_rotation_speed.webm"><source src="//upload.wikimedia.org/wikipedia/commons/transcoded/a/a1/Planets_and_dwarf_planets%27_tilt_and_rotation_speed.webm/Planets_and_dwarf_planets%27_tilt_and_rotation_speed.webm.480p.vp9.webm" type="video/webm; codecs="vp9, opus"" data-transcodekey="480p.vp9.webm" data-width="854" data-height="480" /><source src="//upload.wikimedia.org/wikipedia/commons/a/a1/Planets_and_dwarf_planets%27_tilt_and_rotation_speed.webm" type="video/webm; codecs="vp9"" data-width="1920" data-height="1080" /><source src="//upload.wikimedia.org/wikipedia/commons/transcoded/a/a1/Planets_and_dwarf_planets%27_tilt_and_rotation_speed.webm/Planets_and_dwarf_planets%27_tilt_and_rotation_speed.webm.1080p.vp9.webm" type="video/webm; codecs="vp9, opus"" data-transcodekey="1080p.vp9.webm" data-width="1920" data-height="1080" /><source src="//upload.wikimedia.org/wikipedia/commons/transcoded/a/a1/Planets_and_dwarf_planets%27_tilt_and_rotation_speed.webm/Planets_and_dwarf_planets%27_tilt_and_rotation_speed.webm.144p.mjpeg.mov" type="video/quicktime" data-transcodekey="144p.mjpeg.mov" data-width="256" data-height="144" /><source src="//upload.wikimedia.org/wikipedia/commons/transcoded/a/a1/Planets_and_dwarf_planets%27_tilt_and_rotation_speed.webm/Planets_and_dwarf_planets%27_tilt_and_rotation_speed.webm.240p.vp9.webm" type="video/webm; codecs="vp9, opus"" data-transcodekey="240p.vp9.webm" data-width="426" data-height="240" /><source src="//upload.wikimedia.org/wikipedia/commons/transcoded/a/a1/Planets_and_dwarf_planets%27_tilt_and_rotation_speed.webm/Planets_and_dwarf_planets%27_tilt_and_rotation_speed.webm.360p.vp9.webm" type="video/webm; codecs="vp9, opus"" data-transcodekey="360p.vp9.webm" data-width="640" data-height="360" /><source src="//upload.wikimedia.org/wikipedia/commons/transcoded/a/a1/Planets_and_dwarf_planets%27_tilt_and_rotation_speed.webm/Planets_and_dwarf_planets%27_tilt_and_rotation_speed.webm.360p.webm" type="video/webm; codecs="vp8, vorbis"" data-transcodekey="360p.webm" data-width="640" data-height="360" /></video></span><figcaption>Axial tilt of eight <a href="/wiki/Planet" title="Planet">planets</a> and two dwarf planets, <a href="/wiki/Ceres_(dwarf_planet)" title="Ceres (dwarf planet)">Ceres</a> and <a href="/wiki/Pluto" title="Pluto">Pluto</a></figcaption></figure> <p>All four of the innermost, rocky planets of the <a href="/wiki/Solar_System" title="Solar System">Solar System</a> may have had large variations of their obliquity in the past. Since obliquity is the angle between the axis of rotation and the direction perpendicular to the orbital plane, it changes as the orbital plane changes due to the influence of other planets. But the axis of rotation can also move (<a href="/wiki/Axial_precession" title="Axial precession">axial precession</a>), due to torque exerted by the Sun on a planet's equatorial bulge. Like Earth, all of the rocky planets show axial precession. If the precession rate were very fast the obliquity would actually remain fairly constant even as the orbital plane changes.<sup id="cite_ref-Ward_32-0" class="reference"><a href="#cite_note-Ward-32"><span class="cite-bracket">[</span>32<span class="cite-bracket">]</span></a></sup> The rate varies due to <a href="/wiki/Tidal_acceleration" title="Tidal acceleration">tidal dissipation</a> and <a href="/wiki/Planetary_core" title="Planetary core">core</a>-<a href="/wiki/Mantle_(geology)" title="Mantle (geology)">mantle</a> interaction, among other things. When a planet's precession rate approaches certain values, <a href="/wiki/Orbital_resonance" title="Orbital resonance">orbital resonances</a> may cause large changes in obliquity. The amplitude of the contribution having one of the resonant rates is divided by the difference between the resonant rate and the precession rate, so it becomes large when the two are similar.<sup id="cite_ref-Ward_32-1" class="reference"><a href="#cite_note-Ward-32"><span class="cite-bracket">[</span>32<span class="cite-bracket">]</span></a></sup> </p><p><a href="/wiki/Mercury_(planet)" title="Mercury (planet)">Mercury</a> and <a href="/wiki/Venus" title="Venus">Venus</a> have most likely been stabilized by the tidal dissipation of the Sun. Earth was stabilized by the Moon, as mentioned above, but before its <a href="/wiki/Moon#Formation" title="Moon">formation</a>, Earth, too, could have passed through times of instability. <a href="/wiki/Mars" title="Mars">Mars</a>'s obliquity is quite variable over millions of years and may be in a chaotic state; it varies as much as 0° to 60° over some millions of years, depending on <a href="/wiki/Perturbation_(astronomy)" title="Perturbation (astronomy)">perturbations</a> of the planets.<sup id="cite_ref-LaskarRobutel_26-1" class="reference"><a href="#cite_note-LaskarRobutel-26"><span class="cite-bracket">[</span>26<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-33" class="reference"><a href="#cite_note-33"><span class="cite-bracket">[</span>33<span class="cite-bracket">]</span></a></sup> Some authors dispute that Mars's obliquity is chaotic, and show that tidal dissipation and viscous core-mantle coupling are adequate for it to have reached a fully damped state, similar to Mercury and Venus.<sup id="cite_ref-CorreiaVenusI_3-1" class="reference"><a href="#cite_note-CorreiaVenusI-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Correia2009_34-0" class="reference"><a href="#cite_note-Correia2009-34"><span class="cite-bracket">[</span>34<span class="cite-bracket">]</span></a></sup> </p><p>The occasional shifts in the axial tilt of Mars have been suggested as an explanation for the appearance and disappearance of rivers and lakes over the course of the existence of Mars. A shift could cause a burst of methane into the atmosphere, causing warming, but then the methane would be destroyed and the climate would become arid again.<sup id="cite_ref-35" class="reference"><a href="#cite_note-35"><span class="cite-bracket">[</span>35<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-36" class="reference"><a href="#cite_note-36"><span class="cite-bracket">[</span>36<span class="cite-bracket">]</span></a></sup> </p><p>The obliquities of the outer planets are considered relatively stable. </p> <table class="wikitable" style="margin: 0.5em auto; text-align:right;"> <caption>Axis and rotation of selected Solar System bodies </caption> <tbody><tr> <th rowspan="3">Body </th> <th colspan="4" style="background:#F2FEEC;"><a href="/wiki/NASA" title="NASA">NASA</a>, <a href="/wiki/J2000" class="mw-redirect" title="J2000">J2000</a>.0<sup id="cite_ref-NASA_37-0" class="reference"><a href="#cite_note-NASA-37"><span class="cite-bracket">[</span>37<span class="cite-bracket">]</span></a></sup> epoch </th> <th colspan="4" style="background:#edf3fe;"><a href="/wiki/IAU" class="mw-redirect" title="IAU">IAU</a>, 0h 0 January 2010 <a href="/wiki/Terrestrial_time" class="mw-redirect" title="Terrestrial time">TT</a><sup id="cite_ref-38" class="reference"><a href="#cite_note-38"><span class="cite-bracket">[</span>38<span class="cite-bracket">]</span></a></sup> epoch </th></tr> <tr> <th rowspan="2" style="background: #F2FEEC;">Axial tilt <br />(degrees) </th> <th colspan="2" style="background: #F2FEEC;">North Pole </th> <th rowspan="2" style="background: #F2FEEC;">Rotational <br />period <br />(hours) </th> <th rowspan="2" style="background: #edf3fe;">Axial tilt <br />(degrees) </th> <th colspan="2" style="background: #edf3fe;">North Pole </th> <th rowspan="2" style="background: #edf3fe;">Rotation <br />(deg./day) </th></tr> <tr> <th style="background: #F2FEEC;"><a href="/wiki/Right_ascension" title="Right ascension">R.A.</a> (degrees) </th> <th style="background: #F2FEEC;"><a href="/wiki/Declination" title="Declination">Dec.</a> (degrees) </th> <th style="background: #edf3fe;"><a href="/wiki/Right_ascension" title="Right ascension">R.A.</a> (degrees) </th> <th style="background: #edf3fe;"><a href="/wiki/Declination" title="Declination">Dec.</a> (degrees) </th></tr> <tr> <td style="text-align:left;"><a href="/wiki/Sun" title="Sun">Sun</a> </td> <td>7.25</td> <td>286.13</td> <td>63.87</td> <td>609.12<sup id="cite_ref-39" class="reference"><a href="#cite_note-39"><span class="cite-bracket">[</span>A<span class="cite-bracket">]</span></a></sup></td> <td>7.25<sup id="cite_ref-40" class="reference"><a href="#cite_note-40"><span class="cite-bracket">[</span>B<span class="cite-bracket">]</span></a></sup></td> <td>286.15</td> <td>63.89</td> <td>14.18 </td></tr> <tr> <td style="text-align:left;"><a href="/wiki/Mercury_(planet)" title="Mercury (planet)">Mercury</a> </td> <td>0.03</td> <td>281.01</td> <td>61.41</td> <td>1407.6</td> <td>0.01</td> <td>281.01</td> <td>61.45</td> <td>6.14 </td></tr> <tr> <td style="text-align:left;"><a href="/wiki/Venus" title="Venus">Venus</a> </td> <td>2.64</td> <td>272.76</td> <td>67.16</td> <td>−5832.6</td> <td>2.64</td> <td>272.76</td> <td>67.16</td> <td>−1.48 </td></tr> <tr> <td style="text-align:left;"><a href="/wiki/Earth" title="Earth">Earth</a> </td> <td>23.44</td> <td>0.00</td> <td>90.00</td> <td>23.93</td> <td>23.44</td> <td data-sort-value="" style="background: var(--background-color-interactive, #ececec); color: var(--color-base, inherit); vertical-align: middle; text-align: center;" class="table-na">Undefined</td> <td>90.00</td> <td>360.99 </td></tr> <tr> <td style="text-align:left;"><a href="/wiki/Moon" title="Moon">Moon</a> </td> <td>6.68</td> <td>–</td> <td>–</td> <td>655.73</td> <td>1.54<sup id="cite_ref-41" class="reference"><a href="#cite_note-41"><span class="cite-bracket">[</span>C<span class="cite-bracket">]</span></a></sup></td> <td>270.00</td> <td>66.54</td> <td>13.18 </td></tr> <tr> <td style="text-align:left;"><a href="/wiki/Mars" title="Mars">Mars</a> </td> <td>25.19</td> <td>317.68</td> <td>52.89</td> <td>24.62</td> <td>25.19</td> <td>317.67</td> <td>52.88</td> <td>350.89 </td></tr> <tr> <td style="text-align:left;"><a href="/wiki/Jupiter" title="Jupiter">Jupiter</a> </td> <td>3.13</td> <td>268.06</td> <td>64.50</td> <td>9.93<sup id="cite_ref-clouds_42-0" class="reference"><a href="#cite_note-clouds-42"><span class="cite-bracket">[</span>D<span class="cite-bracket">]</span></a></sup></td> <td>3.12</td> <td>268.06</td> <td>64.50</td> <td>870.54<sup id="cite_ref-clouds_42-1" class="reference"><a href="#cite_note-clouds-42"><span class="cite-bracket">[</span>D<span class="cite-bracket">]</span></a></sup> </td></tr> <tr> <td style="text-align:left;"><a href="/wiki/Saturn" title="Saturn">Saturn</a> </td> <td>26.73</td> <td>40.59</td> <td>83.54</td> <td>10.66<sup id="cite_ref-clouds_42-2" class="reference"><a href="#cite_note-clouds-42"><span class="cite-bracket">[</span>D<span class="cite-bracket">]</span></a></sup></td> <td>26.73</td> <td>40.59</td> <td>83.54</td> <td>810.79<sup id="cite_ref-clouds_42-3" class="reference"><a href="#cite_note-clouds-42"><span class="cite-bracket">[</span>D<span class="cite-bracket">]</span></a></sup> </td></tr> <tr> <td style="text-align:left;"><a href="/wiki/Uranus" title="Uranus">Uranus</a> </td> <td>82.23</td> <td>257.31</td> <td>−15.18</td> <td>−17.24<sup id="cite_ref-clouds_42-4" class="reference"><a href="#cite_note-clouds-42"><span class="cite-bracket">[</span>D<span class="cite-bracket">]</span></a></sup></td> <td>82.23</td> <td>257.31</td> <td>−15.18</td> <td>−501.16<sup id="cite_ref-clouds_42-5" class="reference"><a href="#cite_note-clouds-42"><span class="cite-bracket">[</span>D<span class="cite-bracket">]</span></a></sup> </td></tr> <tr> <td style="text-align:left;"><a href="/wiki/Neptune" title="Neptune">Neptune</a> </td> <td>28.32</td> <td>299.33</td> <td>42.95</td> <td>16.11<sup id="cite_ref-clouds_42-6" class="reference"><a href="#cite_note-clouds-42"><span class="cite-bracket">[</span>D<span class="cite-bracket">]</span></a></sup></td> <td>28.33</td> <td>299.40</td> <td>42.95</td> <td>536.31<sup id="cite_ref-clouds_42-7" class="reference"><a href="#cite_note-clouds-42"><span class="cite-bracket">[</span>D<span class="cite-bracket">]</span></a></sup> </td></tr> <tr> <td style="text-align:left;"><a href="/wiki/Pluto" title="Pluto">Pluto</a><sup id="cite_ref-plutopole_43-0" class="reference"><a href="#cite_note-plutopole-43"><span class="cite-bracket">[</span>E<span class="cite-bracket">]</span></a></sup> </td> <td>57.47</td> <td>312.99<sup id="cite_ref-plutopole_43-1" class="reference"><a href="#cite_note-plutopole-43"><span class="cite-bracket">[</span>E<span class="cite-bracket">]</span></a></sup> </td> <td>6.16<sup id="cite_ref-plutopole_43-2" class="reference"><a href="#cite_note-plutopole-43"><span class="cite-bracket">[</span>E<span class="cite-bracket">]</span></a></sup></td> <td>−153.29</td> <td>60.41</td> <td>312.99</td> <td>6.16</td> <td>−56.36 </td></tr> <tr> <td colspan="9" style="padding:8px 16px; font-size:0.85em;"><style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist reflist-upper-alpha"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-39"><span class="mw-cite-backlink"><b><a href="#cite_ref-39">^</a></b></span> <span class="reference-text">At 16° latitude; the Sun's rotation varies with latitude.</span> </li> <li id="cite_note-40"><span class="mw-cite-backlink"><b><a href="#cite_ref-40">^</a></b></span> <span class="reference-text">With respect to the <a href="/wiki/Ecliptic" title="Ecliptic">ecliptic</a> of 1850.</span> </li> <li id="cite_note-41"><span class="mw-cite-backlink"><b><a href="#cite_ref-41">^</a></b></span> <span class="reference-text">With respect to the ecliptic; the Moon's orbit is inclined 5.16° to the ecliptic.</span> </li> <li id="cite_note-clouds-42"><span class="mw-cite-backlink">^ <a href="#cite_ref-clouds_42-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-clouds_42-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-clouds_42-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-clouds_42-3"><sup><i><b>d</b></i></sup></a> <a href="#cite_ref-clouds_42-4"><sup><i><b>e</b></i></sup></a> <a href="#cite_ref-clouds_42-5"><sup><i><b>f</b></i></sup></a> <a href="#cite_ref-clouds_42-6"><sup><i><b>g</b></i></sup></a> <a href="#cite_ref-clouds_42-7"><sup><i><b>h</b></i></sup></a></span> <span class="reference-text">From the origin of the radio emissions; the visible clouds generally rotate at different rate.</span> </li> <li id="cite_note-plutopole-43"><span class="mw-cite-backlink">^ <a href="#cite_ref-plutopole_43-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-plutopole_43-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-plutopole_43-2"><sup><i><b>c</b></i></sup></a></span> <span class="reference-text">NASA lists the coordinates of Pluto's positive pole; noted values have been reinterpreted to correspond to the north/negative pole.</span> </li> </ol></div></div> </td></tr></tbody></table> <div class="mw-heading mw-heading2"><h2 id="Extrasolar_planets">Extrasolar planets</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Axial_tilt&action=edit&section=9" title="Edit section: Extrasolar planets"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The stellar obliquity <span class="texhtml"><i>ψ</i><sub>s</sub></span>, i.e. the axial tilt of a star with respect to the orbital plane of one of its planets, has been determined for only a few systems. By 2012, 49 stars have had sky-projected spin-orbit misalignment <span class="texhtml"><i>λ</i></span> has been observed,<sup id="cite_ref-HRM_44-0" class="reference"><a href="#cite_note-HRM-44"><span class="cite-bracket">[</span>39<span class="cite-bracket">]</span></a></sup> which serves as a lower limit to <span class="texhtml"><i>ψ</i><sub>s</sub></span>. Most of these measurements rely on the <a href="/wiki/Rossiter%E2%80%93McLaughlin_effect" title="Rossiter–McLaughlin effect">Rossiter–McLaughlin effect</a>. Since the launch of space-based telescopes such as <a href="/wiki/Kepler_space_telescope" title="Kepler space telescope">Kepler space telescope</a>, it has been made possible to determine and estimate the obliquity of an extrasolar planet. The rotational flattening of the planet and the entourage of moons and/or rings, which are traceable with high-precision photometry provide access to planetary obliquity, <span class="texhtml"><i>ψ</i><sub>p</sub></span>. Many extrasolar planets have since had their obliquity determined, such as <a href="/wiki/Kepler-186f" title="Kepler-186f">Kepler-186f</a> and <a href="/wiki/Kepler-413b" title="Kepler-413b">Kepler-413b</a>.<sup id="cite_ref-45" class="reference"><a href="#cite_note-45"><span class="cite-bracket">[</span>40<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-46" class="reference"><a href="#cite_note-46"><span class="cite-bracket">[</span>41<span class="cite-bracket">]</span></a></sup> </p><p>Astrophysicists have applied tidal theories to predict the obliquity of <a href="/wiki/Extrasolar_planets" class="mw-redirect" title="Extrasolar planets">extrasolar planets</a>. It has been shown that the obliquities of exoplanets in the <a href="/wiki/Habitable_zone" title="Habitable zone">habitable zone</a> around low-mass stars tend to be eroded in less than 10<sup>9</sup> years,<sup id="cite_ref-Heller_2011_47-0" class="reference"><a href="#cite_note-Heller_2011-47"><span class="cite-bracket">[</span>42<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Heller_2011b_48-0" class="reference"><a href="#cite_note-Heller_2011b-48"><span class="cite-bracket">[</span>43<span class="cite-bracket">]</span></a></sup> which means that they would not have tilt-induced seasons as Earth has. </p> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Axial_tilt&action=edit&section=10" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Axial_parallelism" title="Axial parallelism">Axial parallelism</a></li> <li><a href="/wiki/Milankovitch_cycles" title="Milankovitch cycles">Milankovitch cycles</a></li> <li><a href="/wiki/Polar_motion" title="Polar motion">Polar motion</a></li> <li><a href="/wiki/Pole_shift" class="mw-redirect" title="Pole shift">Pole shift</a></li> <li><a href="/wiki/Rotation_around_a_fixed_axis" title="Rotation around a fixed axis">Rotation around a fixed axis</a></li> <li><a href="/wiki/True_polar_wander" title="True polar wander">True polar wander</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Axial_tilt&action=edit&section=11" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239543626"><div class="reflist reflist-columns references-column-width" style="column-width: 30em;"> <ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text"> <style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite id="CITEREFU.S._Naval_Observatory_Nautical_Almanac_Office1992" class="citation book cs1">U.S. Naval Observatory Nautical Almanac Office (1992). P. Kenneth Seidelmann (ed.). <i>Explanatory Supplement to the Astronomical Almanac</i>. University Science Books. p. 733. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-935702-68-2" title="Special:BookSources/978-0-935702-68-2"><bdi>978-0-935702-68-2</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Explanatory+Supplement+to+the+Astronomical+Almanac&rft.pages=733&rft.pub=University+Science+Books&rft.date=1992&rft.isbn=978-0-935702-68-2&rft.au=U.S.+Naval+Observatory+Nautical+Almanac+Office&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAxial+tilt" class="Z3988"></span></span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text"><i>Explanatory Supplement 1992</i>, p. 384</span> </li> <li id="cite_note-CorreiaVenusI-3"><span class="mw-cite-backlink">^ <a href="#cite_ref-CorreiaVenusI_3-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-CorreiaVenusI_3-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFCorreia,_Alexandre_C._M.Laskar,_Jacquesde_Surgy,_Olivier_Néron2003" class="citation journal cs1">Correia, Alexandre C. 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(1986). "Secular terms of classical planetary theories using the results of general theory". <i>Astronomy and Astrophysics</i>. <b>157</b> (1): 59–70. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1986A&A...157...59L">1986A&A...157...59L</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Astronomy+and+Astrophysics&rft.atitle=Secular+terms+of+classical+planetary+theories+using+the+results+of+general+theory&rft.volume=157&rft.issue=1&rft.pages=59-70&rft.date=1986&rft_id=info%3Abibcode%2F1986A%26A...157...59L&rft.aulast=Laskar&rft.aufirst=J.&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAxial+tilt" class="Z3988"></span> and erratum to article <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFLaskar1986" class="citation journal cs1">Laskar, J. (1986). "Erratum: Secular terms of classical planetary theories using the results of general theory". <i>Astronomy and Astrophysics</i>. <b>164</b>: 437. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1986A&A...164..437L">1986A&A...164..437L</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Astronomy+and+Astrophysics&rft.atitle=Erratum%3A+Secular+terms+of+classical+planetary+theories+using+the+results+of+general+theory&rft.volume=164&rft.pages=437&rft.date=1986&rft_id=info%3Abibcode%2F1986A%26A...164..437L&rft.aulast=Laskar&rft.aufirst=J.&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAxial+tilt" class="Z3988"></span> Units in article are arcseconds, which may be more convenient.</span> </li> <li id="cite_note-22"><span class="mw-cite-backlink"><b><a href="#cite_ref-22">^</a></b></span> <span class="reference-text"><i>Explanatory Supplement</i> (1961), sec. 2C</span> </li> <li id="cite_note-23"><span class="mw-cite-backlink"><b><a href="#cite_ref-23">^</a></b></span> <span class="reference-text"> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www2.jpl.nasa.gov/basics/bsf2-1.php#nutation">"Basics of Space Flight, Chapter 2"</a>. <i>Jet Propulsion Laboratory/NASA</i>. 29 October 2013<span class="reference-accessdate">. Retrieved <span class="nowrap">26 March</span> 2015</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Jet+Propulsion+Laboratory%2FNASA&rft.atitle=Basics+of+Space+Flight%2C+Chapter+2&rft.date=2013-10-29&rft_id=http%3A%2F%2Fwww2.jpl.nasa.gov%2Fbasics%2Fbsf2-1.php%23nutation&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAxial+tilt" class="Z3988"></span></span> </li> <li id="cite_note-24"><span class="mw-cite-backlink"><b><a href="#cite_ref-24">^</a></b></span> <span class="reference-text"> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMeeus1991" class="citation book cs1">Meeus, Jean (1991). "Chapter 21". <i>Astronomical Algorithms</i>. 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(1993). <a rel="nofollow" class="external text" href="https://web.archive.org/web/20121123093109/http://bugle.imcce.fr/fr/presentation/equipes/ASD/person/Laskar/misc_files/Laskar_Robutel_1993.pdf">"The Chaotic Obliquity of the Planets"</a> <span class="cs1-format">(PDF)</span>. <i><a href="/wiki/Nature_(journal)" title="Nature (journal)">Nature</a></i>. <b>361</b> (6413): 608–612. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1993Natur.361..608L">1993Natur.361..608L</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1038%2F361608a0">10.1038/361608a0</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:4372237">4372237</a>. 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"Habitability of Extrasolar Planets and Tidal Spin Evolution". <i>Origins of Life and Evolution of Biospheres</i>. <b>41</b> (6): 539–43. <a href="/wiki/ArXiv_(identifier)" class="mw-redirect" title="ArXiv (identifier)">arXiv</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://arxiv.org/abs/1108.4347">1108.4347</a></span>. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2011OLEB...41..539H">2011OLEB...41..539H</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1007%2Fs11084-011-9252-3">10.1007/s11084-011-9252-3</a>. <a href="/wiki/PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/22139513">22139513</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:10154158">10154158</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Origins+of+Life+and+Evolution+of+Biospheres&rft.atitle=Habitability+of+Extrasolar+Planets+and+Tidal+Spin+Evolution&rft.volume=41&rft.issue=6&rft.pages=539-43&rft.date=2011&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A10154158%23id-name%3DS2CID&rft_id=info%3Abibcode%2F2011OLEB...41..539H&rft_id=info%3Aarxiv%2F1108.4347&rft_id=info%3Apmid%2F22139513&rft_id=info%3Adoi%2F10.1007%2Fs11084-011-9252-3&rft.aulast=Heller&rft.aufirst=R.&rft.au=Leconte%2C+J.&rft.au=Barnes%2C+R.&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAxial+tilt" class="Z3988"></span></span> </li> </ol></div> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Axial_tilt&action=edit&section=12" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a rel="nofollow" class="external text" href="https://nssdc.gsfc.nasa.gov/planetary/">National Space Science Data Center</a></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFSeidelmann_Archinal_A'hearn_et_al.2007" class="citation journal cs1">Seidelmann, P. Kenneth; Archinal, Brent A.; A'Hearn, Michael F.; et al. (2007). <a rel="nofollow" class="external text" href="https://doi.org/10.1007%2Fs10569-007-9072-y">"Report of the IAU/IAG Working Group on cartographic coordinates and rotational elements: 2006"</a>. <i>Celestial Mechanics and Dynamical Astronomy</i>. <b>98</b> (3): 155–180. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2007CeMDA..98..155S">2007CeMDA..98..155S</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1007%2Fs10569-007-9072-y">10.1007/s10569-007-9072-y</a></span>.</cite><span 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navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td class="navbox-abovebelow" colspan="2"><div id="*_by_century"> <ul><li>by century</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">8th</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Ahmad_Nahavandi" title="Ahmad Nahavandi">Ahmad Nahavandi</a></li> <li><a href="/wiki/Al-Fadl_ibn_Naubakht" title="Al-Fadl ibn Naubakht">Al-Fadl ibn Naubakht</a></li> <li><a href="/wiki/Mu%E1%B8%A5ammad_ibn_Ibr%C4%81h%C4%ABm_al-Faz%C4%81r%C4%AB" title="Muḥammad ibn Ibrāhīm al-Fazārī">Muḥammad ibn Ibrāhīm al-Fazārī</a></li> <li><a href="/wiki/Ibr%C4%81h%C4%ABm_al-Faz%C4%81r%C4%AB" class="mw-redirect" title="Ibrāhīm al-Fazārī">Ibrāhīm al-Fazārī</a></li> <li><a href="/wiki/Mashallah_ibn_Athari" title="Mashallah ibn Athari">Mashallah ibn Athari</a></li> <li><a href="/wiki/Ya%CA%BFq%C5%ABb_ibn_%E1%B9%AC%C4%81riq" class="mw-redirect" title="Yaʿqūb ibn Ṭāriq">Yaʿqūb ibn Ṭāriq</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">9th</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Abu_Ali_al-Khayyat" title="Abu Ali al-Khayyat">Abu Ali al-Khayyat</a></li> <li><a href="/wiki/Abu_Ma%27shar_al-Balkhi" title="Abu Ma'shar al-Balkhi">Abu Ma'shar al-Balkhi</a></li> <li><a href="/wiki/Abu_Said_Gorgani" title="Abu Said Gorgani">Abu Said Gorgani</a></li> <li><a href="/wiki/Al-Farghani" title="Al-Farghani">Al-Farghani</a></li> <li><a href="/wiki/Al-Kindi" title="Al-Kindi">Al-Kindi</a></li> <li><a href="/wiki/Al-Mahani" title="Al-Mahani">Al-Mahani</a></li> <li><a href="/wiki/Abu_Hanifa_Dinawari" title="Abu Hanifa Dinawari">Abu Hanifa Dinawari</a></li> <li><a href="/wiki/Al-%E1%B8%A4ajj%C4%81j_ibn_Y%C5%ABsuf_ibn_Ma%E1%B9%ADar" title="Al-Ḥajjāj ibn Yūsuf ibn Maṭar">Al-Ḥajjāj ibn Yūsuf</a></li> <li><a href="/wiki/Habash_al-Hasib_al-Marwazi" class="mw-redirect" title="Habash al-Hasib al-Marwazi">Al-Marwazi</a></li> <li><a href="/wiki/Ali_ibn_Isa_al-Asturlabi" title="Ali ibn Isa al-Asturlabi">Ali ibn Isa al-Asturlabi</a></li> <li><a href="/wiki/Ban%C5%AB_M%C5%ABs%C4%81_brothers" title="Banū Mūsā brothers">Banū Mūsā brothers</a></li> <li><a href="/wiki/Abu_al-Abbas_Iranshahri" title="Abu al-Abbas Iranshahri">Iranshahri</a></li> <li><a href="/wiki/Khalid_ibn_Abd_al%E2%80%90Malik_al%E2%80%90Marwarrudhi" class="mw-redirect" title="Khalid ibn Abd al‐Malik al‐Marwarrudhi">Khalid ibn Abd al‐Malik al‐Marwarrudhi</a></li> <li><a href="/wiki/Al-Khwarizmi" title="Al-Khwarizmi">Al-Khwarizmi</a></li> <li><a href="/wiki/Sahl_ibn_Bishr" title="Sahl ibn Bishr">Sahl ibn Bishr</a></li> <li><a href="/wiki/Th%C4%81bit_ibn_Qurra" title="Thābit ibn Qurra">Thābit ibn Qurra</a></li> <li><a href="/wiki/Yahya_ibn_Abi_Mansur" title="Yahya ibn Abi Mansur">Yahya ibn Abi Mansur</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">10th</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Abd_al-Rahman_al-Sufi" title="Abd al-Rahman al-Sufi">al-Sufi</a></li> <li><a href="/wiki/Ibn_al-Adami" title="Ibn al-Adami">Ibn</a></li> <li><a href="/wiki/Al-Adami" title="Al-Adami">Al-Adami</a></li> <li><a href="/wiki/Abu-Mahmud_Khojandi" class="mw-redirect" title="Abu-Mahmud Khojandi">al-Khojandi</a></li> <li><a href="/wiki/Abu_Ja%27far_al-Khazin" title="Abu Ja'far al-Khazin">al-Khazin</a></li> <li><a href="/wiki/Abu_Sahl_al-Quhi" title="Abu Sahl al-Quhi">al-Qūhī</a></li> <li><a href="/wiki/Abu_al-Wafa%27_Buzjani" class="mw-redirect" title="Abu al-Wafa' Buzjani">Abu al-Wafa</a></li> <li><a href="/wiki/Ahmad_ibn_Yusuf" title="Ahmad ibn Yusuf">Ahmad ibn Yusuf</a></li> <li><a href="/wiki/Al-Battani" title="Al-Battani">al-Battani</a></li> <li><a href="/wiki/Al-Qabisi" title="Al-Qabisi">Al-Qabisi</a></li> <li><a href="/wiki/Ibn_al-A%27lam" title="Ibn al-A'lam">Ibn al-A'lam</a></li> <li><a href="/wiki/Al-Nayrizi" title="Al-Nayrizi">Al-Nayrizi</a></li> <li><a href="/wiki/Al-Saghani" class="mw-redirect" title="Al-Saghani">Al-Saghani</a></li> <li><a href="/wiki/A%E1%B9%A3-%E1%B9%A2aidan%C4%81n%C4%AB" title="Aṣ-Ṣaidanānī">Aṣ-Ṣaidanānī</a></li> <li><a href="/wiki/Ibn_Yunus" title="Ibn Yunus">Ibn Yunus</a></li> <li><a href="/wiki/Ibrahim_ibn_Sinan" title="Ibrahim ibn Sinan">Ibrahim ibn Sinan</a></li> <li><a href="/wiki/Ma_Yize" title="Ma Yize">Ma Yize</a></li> <li><a href="/wiki/Al-Sijzi" title="Al-Sijzi">al-Sijzi</a></li> <li><a href="/wiki/Al-%CA%BBIjliyyah" title="Al-ʻIjliyyah">Al-ʻIjliyyah</a></li> <li><a href="/wiki/Nastulus" title="Nastulus">Nastulus</a></li> <li><a href="/wiki/Abolfadl_Harawi" title="Abolfadl Harawi">Abolfadl Harawi</a></li> <li><a href="/wiki/Haseb-i_Tabari" title="Haseb-i Tabari">Haseb-i Tabari</a></li> <li><a href="/wiki/Maslama_al-Majriti" title="Maslama al-Majriti">al-Majriti</a></li> <li><a href="/wiki/Abu_al-Hasan_al-Ahwazi" title="Abu al-Hasan al-Ahwazi">Abu al-Hasan al-Ahwazi</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">11th</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Abu_Nasr_Mansur" title="Abu Nasr Mansur">Abu Nasr Mansur</a></li> <li><a href="/wiki/Al-Biruni" title="Al-Biruni">al-Biruni</a></li> <li><a href="/wiki/Ali_ibn_Ridwan" title="Ali ibn Ridwan">Ali ibn Ridwan</a></li> <li><a href="/wiki/Ab%C5%AB_Is%E1%B8%A5%C4%81q_Ibr%C4%81h%C4%ABm_al-Zarq%C4%81l%C4%AB" class="mw-redirect" title="Abū Isḥāq Ibrāhīm al-Zarqālī">Al-Zarqālī</a></li> <li><a href="/wiki/Ibn_al-Samh" title="Ibn al-Samh">Ibn al-Samh</a></li> <li><a href="/wiki/Ibn_al-Haytham" title="Ibn al-Haytham">Alhazen</a></li> <li><a href="/wiki/Avicenna" title="Avicenna">Avicenna</a></li> <li><a href="/wiki/Ibn_al-Saffar" class="mw-redirect" title="Ibn al-Saffar">Ibn al-Saffar</a></li> <li><a href="/wiki/Kushyar_Gilani" title="Kushyar Gilani">Kushyar Gilani</a></li> <li><a href="/wiki/Said_al-Andalusi" title="Said al-Andalusi">Said al-Andalusi</a></li> <li><a href="/wiki/Ibrahim_ibn_Said_al-Sahli" title="Ibrahim ibn Said al-Sahli">Ibrahim ibn Said al-Sahli</a></li> <li><a href="/wiki/Ibn_Mu%27adh_al-Jayyani" title="Ibn Mu'adh al-Jayyani">Ibn Mu'adh al-Jayyani </a></li> <li><a href="/wiki/Al-Isfizari" title="Al-Isfizari">Al-Isfizari</a></li> <li><a href="/wiki/Ali_ibn_Khalaf" title="Ali ibn Khalaf">Ali ibn Khalaf</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">12th</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Nur_ad-Din_al-Bitruji" title="Nur ad-Din al-Bitruji">Al-Bitruji</a></li> <li><a href="/wiki/Avempace" title="Avempace">Avempace</a></li> <li><a href="/wiki/Ibn_Tufail" class="mw-redirect" title="Ibn Tufail">Ibn Tufail</a></li> <li><a href="/wiki/Al-Kharaq%C4%AB" title="Al-Kharaqī">Al-Kharaqī</a></li> <li><a href="/wiki/Al-Khazini" title="Al-Khazini">Al-Khazini</a></li> <li><a href="/wiki/Al-Samawal_al-Maghribi" title="Al-Samawal al-Maghribi">Al-Samawal al-Maghribi</a></li> <li><a href="/wiki/Abu_al-Salt" class="mw-redirect" title="Abu al-Salt">Abu al-Salt</a></li> <li><a href="/wiki/Averroes" title="Averroes">Averroes</a></li> <li><a href="/wiki/Ibn_al-Kammad" title="Ibn al-Kammad">Ibn al-Kammad</a></li> <li><a href="/wiki/Jabir_ibn_Aflah" title="Jabir ibn Aflah">Jabir ibn Aflah</a></li> <li><a href="/wiki/Omar_Khayyam" title="Omar Khayyam">Omar Khayyam</a></li> <li><a href="/wiki/Sharaf_al-Din_al-Tusi" title="Sharaf al-Din al-Tusi">Sharaf al-Din al-Tusi</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">13th</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Ibn_al-Banna%27_al-Marrakushi" title="Ibn al-Banna' al-Marrakushi">Ibn al-Banna' al-Marrakushi</a></li> <li><a href="/wiki/Ibn_al%E2%80%90Ha%27im_al%E2%80%90Ishbili" class="mw-redirect" title="Ibn al‐Ha'im al‐Ishbili">Ibn al‐Ha'im al‐Ishbili</a></li> <li><a href="/wiki/Jamal_ad-Din_Bukhari" title="Jamal ad-Din Bukhari">Jamal ad-Din</a></li> <li><a href="/wiki/Alam_al-Din_al-Hanafi" title="Alam al-Din al-Hanafi">Alam al-Din al-Hanafi</a></li> <li><a href="/wiki/Najm_al%E2%80%90Din_al%E2%80%90Misri" class="mw-redirect" title="Najm al‐Din al‐Misri">Najm al‐Din al‐Misri</a></li> <li><a href="/wiki/Muhyi_al-Din_al-Maghribi" title="Muhyi al-Din al-Maghribi">Muhyi al-Din al-Maghribi</a></li> <li><a href="/wiki/Nasir_al-Din_al-Tusi" title="Nasir al-Din al-Tusi">Nasir al-Din al-Tusi</a></li> <li><a href="/wiki/Qutb_al-Din_al-Shirazi" title="Qutb al-Din al-Shirazi">Qutb al-Din al-Shirazi</a></li> <li><a href="/wiki/Shams_al-Din_al-Samarqandi" title="Shams al-Din al-Samarqandi">Shams al-Din al-Samarqandi</a></li> <li><a href="/wiki/Zakariya_al-Qazwini" title="Zakariya al-Qazwini">Zakariya al-Qazwini</a></li> <li><a href="/wiki/Mu%27ayyad_al-Din_al-Urdi" title="Mu'ayyad al-Din al-Urdi">al-Urdi</a></li> <li><a href="/wiki/Athir_al-Din_al-Abhari" title="Athir al-Din al-Abhari">al-Abhari</a></li> <li><a href="/wiki/Muhammad_ibn_Abi_Bakr_al%E2%80%90Farisi" class="mw-redirect" title="Muhammad ibn Abi Bakr al‐Farisi">Muhammad ibn Abi Bakr al‐Farisi</a></li> <li><a href="/wiki/Abu_Ali_al-Hasan_al-Marrakushi" title="Abu Ali al-Hasan al-Marrakushi">Abu Ali al-Hasan al-Marrakushi</a></li> <li><a href="/wiki/Ibn_Ishaq_al-Tunisi" title="Ibn Ishaq al-Tunisi">Ibn Ishaq al-Tunisi</a></li> <li><a href="/wiki/Ibn_al%E2%80%90Raqqam" class="mw-redirect" title="Ibn al‐Raqqam">Ibn al‐Raqqam</a></li> <li><a href="/wiki/Al-Ashraf_Umar_II" title="Al-Ashraf Umar II">Al-Ashraf Umar II</a></li> <li><a href="/wiki/Fakhr_al-Din_al-Akhlati" title="Fakhr al-Din al-Akhlati">Fakhr al-Din al-Akhlati</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">14th</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Ibn_al-Shatir" title="Ibn al-Shatir">Ibn al-Shatir</a></li> <li><a href="/wiki/Shams_al-Din_Abu_Abd_Allah_al-Khalili" title="Shams al-Din Abu Abd Allah al-Khalili">Al-Khalili</a></li> <li><a href="/wiki/Ibn_Shuayb" title="Ibn Shuayb">Ibn Shuayb</a></li> <li><a href="/wiki/Abu_Muqri_Mohammed_al-Battiwi" title="Abu Muqri Mohammed al-Battiwi"> al-Battiwi</a></li> <li><a href="/wiki/Ab%C5%AB_al%E2%80%90%CA%BFUq%C5%ABl" class="mw-redirect" title="Abū al‐ʿUqūl">Abū al‐ʿUqūl</a></li> <li><a href="/wiki/Al-Wabkanawi" title="Al-Wabkanawi">Al-Wabkanawi</a></li> <li><a href="/wiki/Nizam_al-Din_al-Nisapuri" class="mw-redirect" title="Nizam al-Din al-Nisapuri">Nizam al-Din al-Nisapuri</a></li> <li><a href="/wiki/Abd_al-Rahman_al-Jadiri" title="Abd al-Rahman al-Jadiri"> al-Jadiri</a></li> <li><a href="/wiki/Sadr_al-Shari%27a_al-Asghar" title="Sadr al-Shari'a al-Asghar">Sadr al-Shari'a al-Asghar</a></li> <li><a href="/wiki/Fathullah_Shirazi" title="Fathullah Shirazi">Fathullah Shirazi</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">15th</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Ali_Qushji" title="Ali Qushji">Ali Kuşçu</a></li> <li><a href="/wiki/Abd_al%E2%80%90Wajid" class="mw-redirect" title="Abd al‐Wajid">Abd al‐Wajid</a></li> <li><a href="/wiki/Jamshid_al-Kashi" title="Jamshid al-Kashi">Jamshid al-Kashi</a></li> <li><a href="/wiki/Q%C4%81%E1%B8%8D%C4%AB_Z%C4%81da_al-R%C5%ABm%C4%AB" title="Qāḍī Zāda al-Rūmī">Kadızade Rumi</a></li> <li><a href="/wiki/Ulugh_Beg" title="Ulugh Beg">Ulugh Beg</a></li> <li><a href="/wiki/Sibt_al-Maridini" title="Sibt al-Maridini">Sibt al-Maridini</a></li> <li><a href="/wiki/Ibn_al-Majdi" title="Ibn al-Majdi">Ibn al-Majdi</a></li> <li><a href="/wiki/%27Abd_al-%27Aziz_al-Wafa%27i" title="'Abd al-'Aziz al-Wafa'i">al-Wafa'i</a></li> <li><a href="/wiki/Abu_Ishaq_al-Kubunani" title="Abu Ishaq al-Kubunani">al-Kubunani</a></li> <li><a href="/wiki/%27Abd_al-%27Aziz_al-Wafa%27i" title="'Abd al-'Aziz al-Wafa'i">'Abd al-'Aziz al-Wafa'i</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">16th</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Al-Birjandi" title="Al-Birjandi">Al-Birjandi</a></li> <li><a href="/wiki/Shams_al-Din_al-Khafri" title="Shams al-Din al-Khafri">al-Khafri</a></li> <li><a href="/wiki/Baha%27_al-din_al-%27Amili" class="mw-redirect" title="Baha' al-din al-'Amili">Baha' al-din al-'Amili </a></li> <li><a href="/wiki/Piri_Reis" title="Piri Reis">Piri Reis</a></li> <li><a href="/wiki/Taqi_ad-Din_Muhammad_ibn_Ma%27ruf" title="Taqi ad-Din Muhammad ibn Ma'ruf">Takiyüddin</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">17th</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Yang_Guangxian" title="Yang Guangxian">Yang Guangxian</a></li> <li><a href="/wiki/Ehmed%C3%AA_Xan%C3%AE" title="Ehmedê Xanî">Ehmedê Xanî</a></li> <li><a href="/wiki/Al_Achsasi_al_Mouakket" title="Al Achsasi al Mouakket">Al Achsasi al Mouakket</a></li> <li><a href="/wiki/Muhammad_al-Rudani" title="Muhammad al-Rudani">Muhammad al-Rudani</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks mw-collapsible uncollapsed navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><div id="Topics" style="font-size:114%;margin:0 4em">Topics</div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="Works" scope="row" class="navbox-group" style="width:1%">Works</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/List_of_Arabic_star_names" title="List of Arabic star names">Arabic star names</a></li> <li><a href="/wiki/Islamic_calendar" title="Islamic calendar">Islamic calendar</a></li> <li><i><a href="/wiki/Aja%27ib_al-Makhluqat" title="Aja'ib al-Makhluqat">Aja'ib al-Makhluqat</a></i></li> <li><i><a href="/wiki/Encyclopedia_of_the_Brethren_of_Purity" title="Encyclopedia of the Brethren of Purity">Encyclopedia of the Brethren of Purity</a></i></li> <li><i><a href="/wiki/Tabula_Rogeriana" title="Tabula Rogeriana">Tabula Rogeriana</a></i></li> <li><i><a href="/wiki/The_Book_of_Healing" title="The Book of Healing">The Book of Healing</a></i></li> <li><i><a href="/wiki/The_Remaining_Signs_of_Past_Centuries" title="The Remaining Signs of Past Centuries">The Remaining Signs of Past Centuries</a></i></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;font-weight:normal;"><i><a href="/wiki/Zij" title="Zij">Zij</a></i></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Alfonsine_tables" title="Alfonsine tables">Alfonsine tables</a></li> <li><i><a href="/wiki/Huihui_Lifa" title="Huihui Lifa">Huihui Lifa</a></i></li> <li><i><a href="/wiki/Book_of_Fixed_Stars" class="mw-redirect" title="Book of Fixed Stars">Book of Fixed Stars</a></i></li> <li><a href="/wiki/Toledan_Tables" title="Toledan Tables">Toledan Tables</a></li> <li><i><a href="/wiki/Zij-i_Ilkhani" title="Zij-i Ilkhani">Zij-i Ilkhani</a></i></li> <li><i><a href="/wiki/Zij-i_Sultani" title="Zij-i Sultani">Zij-i Sultani</a></i></li> <li><i><a href="/wiki/Sullam_al-sama%27" title="Sullam al-sama'">Sullam al-sama'</a></i></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Astronomy_in_the_medieval_Islamic_world#Instruments" title="Astronomy in the medieval Islamic world">Instruments</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Alidade" title="Alidade">Alidade</a></li> <li><a href="/wiki/Analog_computer" title="Analog computer">Analog computer</a></li> <li><a href="/wiki/Aperture" title="Aperture">Aperture</a></li> <li><a href="/wiki/Armillary_sphere" title="Armillary sphere">Armillary sphere</a></li> <li><a href="/wiki/Astrolabe" title="Astrolabe">Astrolabe</a></li> <li><a href="/wiki/Astronomical_clock" title="Astronomical clock">Astronomical clock</a></li> <li><a href="/wiki/Armillary_sphere" title="Armillary sphere">Celestial globe</a></li> <li><a href="/wiki/Compass" title="Compass">Compass</a></li> <li><a href="/wiki/Compass_rose" title="Compass rose">Compass rose</a></li> <li><a href="/wiki/Dioptra" title="Dioptra">Dioptra</a></li> <li><a href="/wiki/Equatorial_ring" title="Equatorial ring">Equatorial ring</a></li> <li><a href="/wiki/Equatorium" title="Equatorium">Equatorium</a></li> <li><a href="/wiki/Globe" title="Globe">Globe</a></li> <li><a href="/wiki/Graph_paper" title="Graph paper">Graph paper</a></li> <li><a href="/wiki/Mural_instrument" title="Mural instrument">Mural instrument</a></li> <li><a href="/wiki/Mariner%27s_astrolabe" title="Mariner's astrolabe">Navigational astrolabe</a></li> <li><a href="/wiki/Octant_(instrument)" title="Octant (instrument)">Octant</a></li> <li><a href="/wiki/Planisphere" title="Planisphere">Planisphere</a></li> <li><a href="/wiki/Quadrant_(instrument)" title="Quadrant (instrument)">Quadrant</a></li> <li><a href="/wiki/Sextant_(astronomy)" title="Sextant (astronomy)">Sextant</a></li> <li><a href="/wiki/Shadow_square" title="Shadow square">Shadow square</a></li> <li><a href="/wiki/Sundial" title="Sundial">Sundial</a></li> <li><a href="/wiki/Schema_for_horizontal_dials" title="Schema for horizontal dials">Schema for horizontal sundials</a></li> <li><a href="/wiki/Triquetrum_(astronomy)" title="Triquetrum (astronomy)">Triquetrum</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Concepts</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Almucantar" title="Almucantar">Almucantar</a></li> <li><a href="/wiki/Apsis" title="Apsis">Apogee</a></li> <li><a href="/wiki/Astrology_in_the_medieval_Islamic_world" title="Astrology in the medieval Islamic world">Astrology</a></li> <li><a href="/wiki/Astrophysics" title="Astrophysics">Astrophysics</a></li> <li><a class="mw-selflink selflink">Axial tilt</a></li> <li><a href="/wiki/Azimuth" title="Azimuth">Azimuth</a></li> <li><a href="/wiki/Celestial_mechanics" title="Celestial mechanics">Celestial mechanics</a></li> <li><a href="/wiki/Celestial_spheres" title="Celestial spheres">Celestial spheres</a></li> <li><a href="/wiki/Circular_orbit" title="Circular orbit">Circular orbit</a></li> <li><a href="/wiki/Deferent_and_epicycle" title="Deferent and epicycle">Deferent and epicycle</a></li> <li><a href="/wiki/Earth%27s_rotation" title="Earth's rotation">Earth's rotation</a></li> <li><a href="/wiki/Orbital_eccentricity" title="Orbital eccentricity">Eccentricity</a></li> <li><a href="/wiki/Ecliptic" title="Ecliptic">Ecliptic</a></li> <li><a href="/wiki/Elliptic_orbit" title="Elliptic orbit">Elliptic orbit</a></li> <li><a href="/wiki/Equant" title="Equant">Equant</a></li> <li><a href="/wiki/Galaxy" title="Galaxy">Galaxy</a></li> <li><a href="/wiki/Geocentric_model" title="Geocentric model">Geocentrism</a></li> <li><a href="/wiki/Gravitational_energy" title="Gravitational energy">Gravitational energy</a></li> <li><a href="/wiki/Gravity" title="Gravity">Gravity</a></li> <li><a href="/wiki/Heliocentrism" title="Heliocentrism">Heliocentrism</a></li> <li><a href="/wiki/Inertia" title="Inertia">Inertia</a></li> <li><a href="/wiki/Cosmology_in_medieval_Islam" class="mw-redirect" title="Cosmology in medieval Islam">Islamic cosmology</a></li> <li><a href="/wiki/Moonlight" title="Moonlight">Moonlight</a></li> <li><a href="/wiki/Multiverse" title="Multiverse">Multiverse</a></li> <li><a href="/wiki/Muwaqqit" title="Muwaqqit">Muwaqqit</a></li> <li><a class="mw-selflink selflink">Obliquity</a></li> <li><a href="/wiki/Parallax" title="Parallax">Parallax</a></li> <li><a href="/wiki/Precession" title="Precession">Precession</a></li> <li><a href="/wiki/Qibla" title="Qibla">Qibla</a></li> <li><a href="/wiki/Salah_times" title="Salah times">Salah times</a></li> <li><a href="/wiki/Specific_gravity" class="mw-redirect" title="Specific gravity">Specific gravity</a></li> <li><a href="/wiki/Spherical_Earth" title="Spherical Earth">Spherical Earth</a></li> <li><a href="/wiki/Sublunary_sphere" title="Sublunary sphere">Sublunary sphere</a></li> <li><a href="/wiki/Sunlight" title="Sunlight">Sunlight</a></li> <li><a href="/wiki/Supernova" title="Supernova">Supernova</a></li> <li><a href="/wiki/Temporal_finitism" title="Temporal finitism">Temporal finitism</a></li> <li><a href="/wiki/Trepidation" title="Trepidation">Trepidation</a></li> <li><a href="/wiki/Triangulation" title="Triangulation">Triangulation</a></li> <li><a href="/wiki/Tusi_couple" title="Tusi couple">Tusi couple</a></li> <li><a href="/wiki/Universe" title="Universe">Universe</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Institutions</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Al-Azhar_University" title="Al-Azhar University">Al-Azhar University</a></li> <li><a href="/wiki/House_of_Knowledge" title="House of Knowledge">House of Knowledge</a></li> <li><a href="/wiki/House_of_Wisdom" title="House of Wisdom">House of Wisdom</a></li> <li><a href="/wiki/University_of_al-Qarawiyyin" title="University of al-Qarawiyyin">University of al-Qarawiyyin</a></li> <li><a href="/wiki/Astronomy_in_the_medieval_Islamic_world#Observatories" title="Astronomy in the medieval Islamic world">Observatories</a> <ul><li><span style="font-size:85%;"><a href="/wiki/Constantinople_observatory_of_Taqi_ad-Din" title="Constantinople observatory of Taqi ad-Din">Constantinople (Taqi al-Din)</a></span></li> <li><span style="font-size:85%;"><a href="/wiki/Maragheh_observatory" title="Maragheh observatory">Maragheh</a></span></li> <li><span style="font-size:85%;"><a href="/wiki/Ulugh_Beg_Observatory" title="Ulugh Beg Observatory">Samarkand (Ulugh Beg)</a></span></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Influences</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Babylonian_astronomy" title="Babylonian astronomy">Babylonian astronomy</a></li> <li><a href="/wiki/Egyptian_astronomy" title="Egyptian astronomy">Egyptian astronomy</a></li> <li><a href="/wiki/Ancient_Greek_astronomy#Hellenistic_astronomy" title="Ancient Greek astronomy">Hellenistic astronomy</a></li> <li><a href="/wiki/Indian_astronomy" title="Indian astronomy">Indian astronomy</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Influenced</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Byzantine_science" title="Byzantine science">Byzantine science</a></li> <li><a href="/wiki/Chinese_astronomy" title="Chinese astronomy">Chinese astronomy</a></li> <li><a href="/wiki/European_science_in_the_Middle_Ages" title="European science in the Middle Ages">Medieval European science</a></li> <li><a href="/wiki/Indian_astronomy" title="Indian astronomy">Indian astronomy</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235"></div><div role="navigation" class="navbox" aria-labelledby="Indian_astronomy" style="padding:3px"><table class="nowraplinks mw-collapsible mw-collapsed navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231"><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Indian_astronomy" title="Template:Indian astronomy"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Indian_astronomy" title="Template talk:Indian astronomy"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Indian_astronomy" title="Special:EditPage/Template:Indian astronomy"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Indian_astronomy" style="font-size:114%;margin:0 4em"><a href="/wiki/Indian_astronomy" title="Indian astronomy">Indian astronomy</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%">Astronomers</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Apastamba" class="mw-redirect" title="Apastamba">Apastamba</a></li> <li><a href="/wiki/Aryabhata" title="Aryabhata">Aryabhata I</a></li> <li><a href="/wiki/Aryabhata_II" title="Aryabhata II">Aryabhata II</a></li> <li><a href="/wiki/Vainu_Bappu" title="Vainu Bappu">Vainu Bappu</a></li> <li><a href="/wiki/Bh%C4%81skara_I" title="Bhāskara I">Bhāskara I</a></li> <li><a href="/wiki/Bh%C4%81skara_II" title="Bhāskara II">Bhāskara II</a></li> <li><a href="/wiki/Baudhayana" class="mw-redirect" title="Baudhayana">Baudhayana</a></li> <li><a href="/wiki/Brahmagupta" title="Brahmagupta">Brahmagupta</a></li> <li><a href="/wiki/Sandip_Chakrabarti" title="Sandip Chakrabarti">Sandip Chakrabarti</a></li> <li><a href="/wiki/Radhagobinda_Chandra" class="mw-redirect" title="Radhagobinda Chandra">Radhagobinda Chandra</a></li> <li><a href="/wiki/Subrahmanyan_Chandrasekhar" title="Subrahmanyan Chandrasekhar">Subrahmanyan Chandrasekhar</a></li> <li><a href="/wiki/Amil_Kumar_Das" class="mw-redirect" title="Amil Kumar Das">Amil Kumar Das</a></li> <li><a href="/wiki/P_Devadas" class="mw-redirect" title="P Devadas">P. Devadas</a></li> <li><a href="/wiki/Gautama_Siddha" title="Gautama Siddha">Gautama Siddha</a></li> <li><a href="/wiki/M_K_Das_Gupta" class="mw-redirect" title="M K Das Gupta">M. K. Das Gupta</a></li> <li><a href="/wiki/Jyesthadeva" class="mw-redirect" title="Jyesthadeva">Jyesthadeva</a></li> <li><a href="/wiki/Kamalakara" title="Kamalakara">Kamalakara</a></li> <li><a href="/wiki/Katyayana" class="mw-redirect" title="Katyayana">Katyayana</a></li> <li><a href="/wiki/Lagadha" class="mw-redirect" title="Lagadha">Lagadha</a></li> <li><a href="/wiki/Lalla" title="Lalla">Lalla</a></li> <li><a href="/wiki/Madhava_of_Sangamagrama" title="Madhava of Sangamagrama">Madhava of Sangamagrama</a></li> <li><a href="/wiki/Prasanta_Chandra_Mahalanobis" title="Prasanta Chandra Mahalanobis">Prasanta Chandra Mahalanobis</a></li> <li><a href="/wiki/Mahavira_(mathematician)" class="mw-redirect" title="Mahavira (mathematician)">Mahavira</a></li> <li><a href="/wiki/Manava" title="Manava">Manava</a></li> <li><a href="/wiki/Jayant_Narlikar" title="Jayant Narlikar">Jayant Narlikar</a></li> <li><a href="/wiki/Parameshvara" class="mw-redirect" title="Parameshvara">Parameshvara</a></li> <li><a href="/wiki/Achyuta_Pisharati" class="mw-redirect" title="Achyuta Pisharati">Achyuta Pisharati</a></li> <li><a href="/wiki/Venkatraman_Radhakrishnan" title="Venkatraman Radhakrishnan">Venkatraman Radhakrishnan</a></li> <li><a href="/wiki/J._J._Rawal" class="mw-redirect" title="J. J. Rawal">J. J. Rawal</a></li> <li><a href="/wiki/Megh_Nad_Saha" class="mw-redirect" title="Megh Nad Saha">Megh Nad Saha</a></li> <li><a href="/wiki/Jagannatha_Samrat" title="Jagannatha Samrat">Jagannatha Samrat</a></li> <li><a href="/wiki/Bapudeva_Sastri" title="Bapudeva Sastri">Bapudeva Sastri</a></li> <li><a href="/wiki/Jai_Singh_II_of_Amber" class="mw-redirect" title="Jai Singh II of Amber">Jai Singh II of Amber</a></li> <li><a href="/wiki/Nilakantha_Somayaji" title="Nilakantha Somayaji">Nilakantha Somayaji</a></li> <li><a href="/wiki/Sripati" class="mw-redirect" title="Sripati">Sripati</a></li> <li><a href="/wiki/Mahendra_Suri" class="mw-redirect" title="Mahendra Suri">Mahendra Suri</a></li> <li><a href="/wiki/Govind_Swarup" title="Govind Swarup">Govind Swarup</a></li> <li><a href="/wiki/Utpala_(astronomer)" title="Utpala (astronomer)">Utpala</a></li> <li><a href="/wiki/Varahamihira" class="mw-redirect" title="Varahamihira">Varahamihira</a></li> <li><a href="/wiki/Shankara_Variyar" class="mw-redirect" title="Shankara Variyar">Shankara Variyar</a></li> <li><a href="/wiki/Vasistha" class="mw-redirect" title="Vasistha">Vasistha</a></li> <li><a href="/wiki/Yajnavalkya" title="Yajnavalkya">Yajnavalkya</a></li> <li><a href="/wiki/Pathani_Samanta" title="Pathani Samanta">Pathani Samanta</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Works</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><i><a href="/wiki/Aryabhatiya" title="Aryabhatiya">Aryabhatiya</a></i></li> <li><i><b><a href="/wiki/Brahmana" title="Brahmana">Brahmanas</a></b></i> <ul><li><i><a href="/wiki/Aitareya_Brahmana" title="Aitareya Brahmana">Aitareya Brahmana</a></i></li> <li><i><a href="/wiki/Shatapatha_Brahmana" title="Shatapatha Brahmana">Shatapatha Brahmana</a></i></li></ul></li> <li><i><span title="International Alphabet of Sanskrit transliteration"><i lang="sa-Latn"><a href="/wiki/B%E1%B9%9Bhat_Sa%E1%B9%83hit%C4%81" title="Bṛhat Saṃhitā">Bṛhat Saṃhitā</a></i></span></i></li> <li><i><a href="/wiki/Ganitagannadi" title="Ganitagannadi">Ganitagannadi</a></i></li> <li><i><a href="/wiki/Jyotirmimamsa" title="Jyotirmimamsa">Jyotirmimamsa</a></i></li> <li><i><a href="/wiki/Shulba_Sutras" title="Shulba Sutras">Shulba Sutras</a></i></li> <li><i><a href="/wiki/Panchangam" title="Panchangam">Panchangam</a></i></li> <li><i><a href="/wiki/Khandakhadyaka" title="Khandakhadyaka">Khandakhadyaka</a></i></li> <li><i><a href="/wiki/Mahadevi_(astronomy_book)" title="Mahadevi (astronomy book)">Mahādevī</a></i></li> <li><i><a href="/wiki/Makarandasarini" title="Makarandasarini">Makarandasarini</a></i></li> <li><i><b><a href="/wiki/Siddhanta_(astronomy)" class="mw-redirect" title="Siddhanta (astronomy)">Siddhantas</a></b></i> <ul><li><i><a href="/wiki/Br%C4%81hmasphu%E1%B9%ADasiddh%C4%81nta" title="Brāhmasphuṭasiddhānta">Brāhmasphuṭasiddhānta</a></i></li> <li><i><a href="/wiki/Maha-Siddhanta" class="mw-redirect" title="Maha-Siddhanta">Maha-Siddhanta</a></i></li> <li><i><a href="/wiki/Pancha-siddhantika" title="Pancha-siddhantika">Pancha-Siddhantika</a></i></li> <li><i><a href="/wiki/Paulisa_Siddhanta" title="Paulisa Siddhanta">Paulisa Siddhanta</a></i></li> <li><i><a href="/wiki/Paitamaha_Siddhanta" class="mw-redirect" title="Paitamaha Siddhanta">Paitamaha Siddhanta</a></i></li> <li><a href="/wiki/R%C4%81jam%E1%B9%9Bg%C4%81%E1%B9%85ka_(astronomy_book)" title="Rājamṛgāṅka (astronomy book)">Rājamṛgāṅka (astronomy book)</a></li> <li><i><a href="/wiki/Romaka_Siddhanta" title="Romaka Siddhanta">Romaka Siddhanta</a></i></li> <li><i><a href="/wiki/Surya_Siddhanta" title="Surya Siddhanta">Surya Siddhanta</a></i></li> <li><i><a href="/wiki/Vasishtha_Siddhanta" title="Vasishtha Siddhanta">Vasishtha Siddhanta</a></i></li></ul></li> <li><i><a href="/wiki/Tantrasangraha" class="mw-redirect" title="Tantrasangraha">Tantrasangraha</a></i></li> <li><i><a href="/wiki/Treatise_on_Astrology_of_the_Kaiyuan_Era" title="Treatise on Astrology of the Kaiyuan Era">Treatise on Astrology of the Kaiyuan Era</a></i></li> <li><i><a href="/wiki/V%C4%81kyakara%E1%B9%87a" title="Vākyakaraṇa">Vākyakaraṇa</a></i></li> <li><i><a href="/wiki/Vedanga_Jyotisha" title="Vedanga Jyotisha">Vedanga Jyotisha</a></i></li> <li><i><b><a href="/wiki/Vedas" title="Vedas">Vedas</a></b></i> <ul><li><i><a href="/wiki/Atharvaveda" title="Atharvaveda">Atharvaveda</a></i></li> <li><i><a href="/wiki/Rigveda" title="Rigveda">Rigveda</a></i></li></ul></li> <li><i><a href="/wiki/Yavanajataka" title="Yavanajataka">Yavanajataka</a></i></li> <li><i><a href="/wiki/Zij" title="Zij">Zij</a></i></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Instruments</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Armillary_sphere" title="Armillary sphere">Armillary sphere</a></li> <li><a href="/wiki/Astrolabe" title="Astrolabe">Astrolabe</a></li> <li><a href="/wiki/Armillary_sphere" title="Armillary sphere">Celestial globe</a></li> <li><a href="/wiki/Compass" title="Compass">Compass</a></li> <li><a href="/wiki/Jacob%27s_staff" title="Jacob's staff">Cross-staff</a></li> <li><a href="/wiki/Dioptra" title="Dioptra">Dioptra</a></li> <li><a href="/wiki/Equatorial_ring" title="Equatorial ring">Equatorial ring</a></li> <li><a href="/wiki/Equatorial_sundial" class="mw-redirect" title="Equatorial sundial">Equatorial sundial</a></li> <li><a href="/wiki/Globe" title="Globe">Globe</a></li> <li><a href="/wiki/Gnomon" title="Gnomon">Gnomon</a></li> <li><a href="/wiki/Mural_instrument" title="Mural instrument">Mural instrument</a></li> <li><a href="/wiki/Quadrant_(instrument)" title="Quadrant (instrument)">Quadrant</a></li> <li><a href="/wiki/Sextant_(astronomical)" class="mw-redirect" title="Sextant (astronomical)">Sextant</a></li> <li><a href="/wiki/Sundial" title="Sundial">Sundial</a></li> <li><a href="/wiki/Triquetrum_(astronomy)" title="Triquetrum (astronomy)">Triquetrum</a></li> <li><a href="/wiki/Water_clock" title="Water clock">Water clock</a></li> <li><a href="/wiki/Yantraraja" title="Yantraraja">Yantraraja</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Concepts</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a class="mw-selflink selflink">Axial tilt</a></li> <li><a href="/wiki/Azimuth" title="Azimuth">Azimuth</a></li> <li><a href="/wiki/Cardinal_direction" title="Cardinal direction">Cardinal direction</a></li> <li><a href="/wiki/Celestial_equator" title="Celestial equator">Celestial equator</a></li> <li><a href="/wiki/Celestial_sphere" title="Celestial sphere">Celestial sphere</a></li> <li><a href="/wiki/Celestial_spheres" title="Celestial spheres">Celestial spheres</a></li> <li><a href="/wiki/Center_of_mass" title="Center of mass">Center of mass</a></li> <li><a href="/wiki/Circular_orbit" title="Circular orbit">Circular orbit</a></li> <li><a href="/wiki/Deferent_and_epicycle" title="Deferent and epicycle">Deferent and epicycle</a></li> <li><a href="/wiki/Earth%27s_rotation" title="Earth's rotation">Earth's rotation</a></li> <li><a href="/wiki/Orbital_eccentricity" title="Orbital eccentricity">Eccentricity</a></li> <li><a href="/wiki/Ecliptic" title="Ecliptic">Ecliptic</a></li> <li><a href="/wiki/Elliptic_orbit" title="Elliptic orbit">Elliptic orbit</a></li> <li><a href="/wiki/Equant" title="Equant">Equant</a></li> <li><a href="/wiki/Geocentric_model" title="Geocentric model">Geocentrism</a></li> <li><a href="/wiki/Tychonic_system" title="Tychonic system">Geoheliocentrism</a></li> <li><a href="/wiki/Globe" title="Globe">Globe</a></li> <li><a href="/wiki/Gravitation" class="mw-redirect" title="Gravitation">Gravity</a></li> <li><a href="/wiki/Heliocentrism" title="Heliocentrism">Heliocentrism</a></li> <li><a href="/wiki/Hindu_units_of_time" title="Hindu units of time">Hindu units of time</a></li> <li><span title="International Alphabet of Sanskrit transliteration"><i lang="sa-Latn"><a href="/wiki/Jyoti%E1%B9%A3a" class="mw-redirect" title="Jyotiṣa">Jyotiṣa</a></i></span></li> <li><a href="/wiki/Kali_ahargana" title="Kali ahargana">Kali ahargaṇa</a></li> <li><b><a href="/wiki/Kalpa_(aeon)" class="mw-redirect" title="Kalpa (aeon)">Kalpa</a></b></li> <li><a href="/wiki/Karana_(pancanga)" class="mw-redirect" title="Karana (pancanga)">Karana</a></li> <li><a href="/wiki/Manvantara" title="Manvantara">Manvantara</a></li> <li><a href="/wiki/Moonlight" title="Moonlight">Moonlight</a></li> <li><a href="/wiki/Nakshatra" title="Nakshatra">Nakshatra</a></li> <li><a href="/wiki/Nityayoga" title="Nityayoga">Nityayoga</a></li> <li><a href="/wiki/Parallax" title="Parallax">Parallax</a></li> <li><a href="/wiki/Precession" title="Precession">Precession</a></li> <li><a href="/wiki/Ritu_(Indian_season)" class="mw-redirect" title="Ritu (Indian season)">Ritu</a></li> <li><a href="/wiki/Spherical_Earth" title="Spherical Earth">Spherical Earth</a></li> <li><a href="/wiki/Sunlight" title="Sunlight">Sunlight</a></li> <li><a href="/wiki/Tithi" title="Tithi">Tithi</a></li> <li><a href="/wiki/V%C4%81ra_(astronomy)" title="Vāra (astronomy)">Vāra</a></li> <li><b><a href="/wiki/Yuga" title="Yuga">Yuga</a></b></li> <li><a href="/wiki/Astrological_sign" title="Astrological sign">Zodiacal sign</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Centres</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Jantar_Mantar" title="Jantar Mantar">Jantar Mantar</a> <ul><li><a href="/wiki/Jantar_Mantar,_Jaipur" title="Jantar Mantar, Jaipur">Jaipur</a></li> <li><a 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