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Available in 21 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-21" 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">21 languages</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D9%83%D9%88%D9%83%D8%A8_%D9%87%D9%8A%D9%84%D9%8A%D9%88%D9%85" title="كوكب هيليوم – Arabic" lang="ar" hreflang="ar" data-title="كوكب هيليوم" data-language-autonym="العربية" data-language-local-name="Arabic" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/Planeta_d%27heli" title="Planeta d'heli – Catalan" lang="ca" hreflang="ca" data-title="Planeta d'heli" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Planeta_de_helio" title="Planeta de helio – Spanish" lang="es" hreflang="es" data-title="Planeta de helio" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%D8%B3%DB%8C%D8%A7%D8%B1%D9%87_%D9%87%D9%84%DB%8C%D9%88%D9%85%DB%8C" title="سیاره هلیومی – Persian" lang="fa" hreflang="fa" data-title="سیاره هلیومی" 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/Plan%C3%A8te_d%27h%C3%A9lium" title="Planète d'hélium – French" lang="fr" hreflang="fr" data-title="Planète d'hélium" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%ED%97%AC%EB%A5%A8_%ED%96%89%EC%84%B1" title="헬륨 행성 – Korean" lang="ko" hreflang="ko" data-title="헬륨 행성" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-id mw-list-item"><a href="https://id.wikipedia.org/wiki/Planet_helium" title="Planet helium – Indonesian" lang="id" hreflang="id" data-title="Planet helium" 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-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Pianeta_di_elio" title="Pianeta di elio – Italian" lang="it" hreflang="it" data-title="Pianeta di elio" 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%9B%D7%95%D7%9B%D7%91_%D7%9C%D7%9B%D7%AA_%D7%94%D7%9C%D7%99%D7%95%D7%9D" title="כוכב לכת הליום – Hebrew" lang="he" hreflang="he" data-title="כוכב לכת הליום" data-language-autonym="עברית" data-language-local-name="Hebrew" class="interlanguage-link-target"><span>עברית</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/%E3%83%98%E3%83%AA%E3%82%A6%E3%83%A0%E6%83%91%E6%98%9F" title="ヘリウム惑星 – Japanese" lang="ja" hreflang="ja" data-title="ヘリウム惑星" 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-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/Planeta_helowa" title="Planeta helowa – Polish" lang="pl" hreflang="pl" data-title="Planeta helowa" data-language-autonym="Polski" data-language-local-name="Polish" class="interlanguage-link-target"><span>Polski</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/Planeta_de_h%C3%A9lio" title="Planeta de hélio – Portuguese" lang="pt" hreflang="pt" data-title="Planeta de hélio" 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/Planet%C4%83_de_heliu" title="Planetă de heliu – Romanian" lang="ro" hreflang="ro" data-title="Planetă de heliu" 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%93%D0%B5%D0%BB%D0%B8%D0%B5%D0%B2%D0%B0%D1%8F_%D0%BF%D0%BB%D0%B0%D0%BD%D0%B5%D1%82%D0%B0" title="Гелиевая планета – Russian" lang="ru" hreflang="ru" data-title="Гелиевая планета" data-language-autonym="Русский" data-language-local-name="Russian" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-fi mw-list-item"><a href="https://fi.wikipedia.org/wiki/Heliumplaneetta" title="Heliumplaneetta – Finnish" lang="fi" hreflang="fi" data-title="Heliumplaneetta" data-language-autonym="Suomi" data-language-local-name="Finnish" class="interlanguage-link-target"><span>Suomi</span></a></li><li class="interlanguage-link interwiki-th mw-list-item"><a href="https://th.wikipedia.org/wiki/%E0%B8%94%E0%B8%B2%E0%B8%A7%E0%B9%80%E0%B8%84%E0%B8%A3%E0%B8%B2%E0%B8%B0%E0%B8%AB%E0%B9%8C%E0%B8%AE%E0%B8%B5%E0%B9%80%E0%B8%A5%E0%B8%B5%E0%B8%A2%E0%B8%A1" title="ดาวเคราะห์ฮีเลียม – Thai" lang="th" hreflang="th" data-title="ดาวเคราะห์ฮีเลียม" data-language-autonym="ไทย" data-language-local-name="Thai" class="interlanguage-link-target"><span>ไทย</span></a></li><li class="interlanguage-link interwiki-tr mw-list-item"><a href="https://tr.wikipedia.org/wiki/Helyum_gezegeni" title="Helyum gezegeni – Turkish" lang="tr" hreflang="tr" data-title="Helyum gezegeni" data-language-autonym="Türkçe" data-language-local-name="Turkish" class="interlanguage-link-target"><span>Türkçe</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/%D0%93%D0%B5%D0%BB%D1%96%D1%94%D0%B2%D0%B0_%D0%BF%D0%BB%D0%B0%D0%BD%D0%B5%D1%82%D0%B0" title="Гелієва планета – Ukrainian" lang="uk" hreflang="uk" data-title="Гелієва планета" 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class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none">Planet with helium-dominated atmosphere</div> <figure class="mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:PIA19344-HeliumShroudedPlanet-ArtistConcept-20150611.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/9/92/PIA19344-HeliumShroudedPlanet-ArtistConcept-20150611.jpg/250px-PIA19344-HeliumShroudedPlanet-ArtistConcept-20150611.jpg" decoding="async" width="250" height="141" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/9/92/PIA19344-HeliumShroudedPlanet-ArtistConcept-20150611.jpg/375px-PIA19344-HeliumShroudedPlanet-ArtistConcept-20150611.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/9/92/PIA19344-HeliumShroudedPlanet-ArtistConcept-20150611.jpg/500px-PIA19344-HeliumShroudedPlanet-ArtistConcept-20150611.jpg 2x" data-file-width="7680" data-file-height="4320" /></a><figcaption>Helium planets would have a white or grey hue. (Artist's conception shown.)</figcaption></figure> <p>A <b>helium planet</b> is a planet with a <a href="/wiki/Helium" title="Helium">helium</a>-dominated atmosphere. This contrasts with ordinary <a href="/wiki/Gas_giant" title="Gas giant">gas giants</a> such as <a href="/wiki/Jupiter" title="Jupiter">Jupiter</a> and <a href="/wiki/Saturn" title="Saturn">Saturn</a>, whose atmospheres consist primarily of <a href="/wiki/Hydrogen" title="Hydrogen">hydrogen</a>, with helium as a secondary component only. Helium planets might form in a variety of ways. <a href="/wiki/Gliese_436_b" title="Gliese 436 b">Gliese 436 b</a> is a possible helium planet. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Formation">Formation</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Helium_planet&action=edit&section=1" title="Edit section: Formation"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>There are several hypotheses for how a helium planet might form. </p> <div class="mw-heading mw-heading3"><h3 id="Hydrogen_evaporation_from_giant_planets">Hydrogen evaporation from giant planets</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Helium_planet&action=edit&section=2" title="Edit section: Hydrogen evaporation from giant planets"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <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 tright"><div class="thumbinner multiimageinner" style="width:292px;max-width:292px"><div class="trow"><div class="tsingle" style="width:290px;max-width:290px"><div class="thumbimage" style="height:115px;overflow:hidden"><span typeof="mw:File"><a href="/wiki/File:PIA19345_Helium_Atmosphere_Formation_0_.png" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/f/f2/PIA19345_Helium_Atmosphere_Formation_0_.png/288px-PIA19345_Helium_Atmosphere_Formation_0_.png" decoding="async" width="288" height="116" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/f2/PIA19345_Helium_Atmosphere_Formation_0_.png/432px-PIA19345_Helium_Atmosphere_Formation_0_.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/f2/PIA19345_Helium_Atmosphere_Formation_0_.png/576px-PIA19345_Helium_Atmosphere_Formation_0_.png 2x" data-file-width="2284" data-file-height="918" /></a></span></div></div></div><div class="trow"><div class="tsingle" style="width:290px;max-width:290px"><div class="thumbimage" style="height:115px;overflow:hidden"><span typeof="mw:File"><a href="/wiki/File:PIA19345_Helium_Atmosphere_Formation_0.1_Gyr.png" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/a/a9/PIA19345_Helium_Atmosphere_Formation_0.1_Gyr.png/288px-PIA19345_Helium_Atmosphere_Formation_0.1_Gyr.png" decoding="async" width="288" height="116" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/a/a9/PIA19345_Helium_Atmosphere_Formation_0.1_Gyr.png/432px-PIA19345_Helium_Atmosphere_Formation_0.1_Gyr.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/a/a9/PIA19345_Helium_Atmosphere_Formation_0.1_Gyr.png/576px-PIA19345_Helium_Atmosphere_Formation_0.1_Gyr.png 2x" data-file-width="2284" data-file-height="918" /></a></span></div></div></div><div class="trow"><div class="tsingle" style="width:290px;max-width:290px"><div class="thumbimage" style="height:115px;overflow:hidden"><span typeof="mw:File"><a href="/wiki/File:PIA19345_Helium_Atmosphere_Formation_several_Gyr.png" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/9/9e/PIA19345_Helium_Atmosphere_Formation_several_Gyr.png/288px-PIA19345_Helium_Atmosphere_Formation_several_Gyr.png" decoding="async" width="288" height="116" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/9/9e/PIA19345_Helium_Atmosphere_Formation_several_Gyr.png/432px-PIA19345_Helium_Atmosphere_Formation_several_Gyr.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/9/9e/PIA19345_Helium_Atmosphere_Formation_several_Gyr.png/576px-PIA19345_Helium_Atmosphere_Formation_several_Gyr.png 2x" data-file-width="2284" data-file-height="918" /></a></span></div></div></div><div class="trow" style="display:flex"><div class="thumbcaption">Formation of a helium planet from a hot giant planet through <a href="/wiki/Atmospheric_escape" title="Atmospheric escape">atmospheric escape</a>, possibly like <a href="/wiki/Gliese_436_b" title="Gliese 436 b">Gliese 436 b</a>.</div></div></div></div> <p>A helium planet might form via hydrogen evaporation from a <a href="/wiki/Gas_planet" class="mw-redirect" title="Gas planet">gaseous planet</a> orbiting close to a star. The star will drive off lighter gases more effectively through evaporation than heavier gasses, and over time deplete the hydrogen, leaving a greater proportion of helium behind.<sup id="cite_ref-SpaceDaily-2015-06-16_1-0" class="reference"><a href="#cite_note-SpaceDaily-2015-06-16-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p><p>A scenario for forming helium planets from regular <a href="/wiki/Giant_planet" title="Giant planet">giant planets</a> involves an <a href="/wiki/Ice_giant" title="Ice giant">ice giant</a>, in an orbit so close to its host star that the <a href="/wiki/Hydrogen" title="Hydrogen">hydrogen</a> effectively boils out of the atmosphere, evaporating from and escaping the gravitational hold of the planet. The planet's atmosphere will experience a large energy input and because light gases are more readily evaporated than heavier gases, the proportion of helium will steadily increase in the remaining atmosphere. Such a process will take some time to stabilize and completely drive out all the hydrogen, perhaps on the order of 10 billion years, depending on the precise physical conditions and the nature of the planet and the star. <a href="/wiki/Hot_Neptune" title="Hot Neptune">Hot Neptunes</a> are candidates for such a scenario. </p><p>The loss of hydrogen also leads to a depletion of <a href="/wiki/Methane" title="Methane">methane</a> in the atmosphere. On ice giants, methane naturally forms a cycle of melting, evaporation, breakdown and subsequent recombination and condensation. But as hydrogen gets depleted, a fraction of the carbon atoms will not be able to recombine with free hydrogen in the atmosphere and over time this will lead to an overall loss of methane. With time, the methane in the atmospheres of hot ice giants will also get depleted.<sup id="cite_ref-SpaceDaily-2015-06-16_1-1" class="reference"><a href="#cite_note-SpaceDaily-2015-06-16-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="White_dwarf_remnants">White dwarf remnants</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Helium_planet&action=edit&section=3" title="Edit section: White dwarf remnants"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>A helium-rich planetary object may also form from a low-mass <a href="/wiki/White_dwarf" title="White dwarf">white dwarf</a>, which gets depleted of hydrogen via mass transfer in a close binary system with a second, massive object like a <a href="/wiki/Neutron_star" title="Neutron star">neutron star</a>. </p><p>One scenario involves an <a href="/wiki/AM_Canum_Venaticorum_star" title="AM Canum Venaticorum star">AM CVn type</a> of symbiotic binary star composed of two helium-core white dwarfs surrounded by a circumbinary helium accretion disk formed during mass transfer from the less massive to the more massive white dwarf. After it loses most of its mass, the less massive white dwarf may approach planetary mass.<sup id="cite_ref-2007ApJ...669.1279S_2-0" class="reference"><a href="#cite_note-2007ApJ...669.1279S-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Characteristics">Characteristics</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Helium_planet&action=edit&section=4" title="Edit section: Characteristics"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Helium planets are expected to be distinguishable from regular hydrogen-dominated planets by strong evidence of <a href="/wiki/Carbon_monoxide" title="Carbon monoxide">carbon monoxide</a> and <a href="/wiki/Carbon_dioxide" title="Carbon dioxide">carbon dioxide</a> in the atmosphere. Due to hydrogen depletion, the expected <a href="/wiki/Methane" title="Methane">methane</a> in the atmosphere cannot form because there is no hydrogen for the carbon to combine with, hence carbon combines with oxygen instead, forming CO and CO<sub style="font-size: 80%;vertical-align: -0.35em">2</sub>. Due to the atmospheric composition, helium planets are expected to be white or grey in appearance.<sup id="cite_ref-SpaceDaily-2015-06-16_1-2" class="reference"><a href="#cite_note-SpaceDaily-2015-06-16-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> Such a signature can be found in Gliese 436 b, which has a predominance of carbon monoxide, and is hypothesized to be a helium planet.<sup id="cite_ref-SpaceDaily-2015-06-16_1-3" class="reference"><a href="#cite_note-SpaceDaily-2015-06-16-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </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=Helium_planet&action=edit&section=5" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Planet#Formation" title="Planet">Planet § Formation</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=Helium_planet&action=edit&section=6" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <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 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.cs1-maint{color:#18911f}}</style><cite class="citation news cs1"><a rel="nofollow" class="external text" href="http://www.spacedaily.com/reports/Helium_Shrouded_Planets_May_Be_Common_in_Our_Galaxy_999.html">"Helium-Shrouded Planets May Be Common in Our Galaxy"</a>. SpaceDaily. 16 June 2015<span class="reference-accessdate">. Retrieved <span class="nowrap">3 August</span> 2015</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.atitle=Helium-Shrouded+Planets+May+Be+Common+in+Our+Galaxy&rft.date=2015-06-16&rft_id=http%3A%2F%2Fwww.spacedaily.com%2Freports%2FHelium_Shrouded_Planets_May_Be_Common_in_Our_Galaxy_999.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AHelium+planet" class="Z3988"></span></span> </li> <li id="cite_note-2007ApJ...669.1279S-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2007ApJ...669.1279S_2-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFSeagerM._KuchnerC._Hier-MajumderB._Militzer2007" class="citation journal cs1">Seager, S.; M. Kuchner; C. Hier-Majumder; B. Militzer (2007). "Mass-Radius Relationships for Solid Exoplanets". <i>Astrophysical Journal</i>. <b>669</b> (2): 1279–1297. <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/0707.2895">0707.2895</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/2007ApJ...669.1279S">2007ApJ...669.1279S</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1086%2F521346">10.1086/521346</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:8369390">8369390</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Astrophysical+Journal&rft.atitle=Mass-Radius+Relationships+for+Solid+Exoplanets&rft.volume=669&rft.issue=2&rft.pages=1279-1297&rft.date=2007&rft_id=info%3Aarxiv%2F0707.2895&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A8369390%23id-name%3DS2CID&rft_id=info%3Adoi%2F10.1086%2F521346&rft_id=info%3Abibcode%2F2007ApJ...669.1279S&rft.aulast=Seager&rft.aufirst=S.&rft.au=M.+Kuchner&rft.au=C.+Hier-Majumder&rft.au=B.+Militzer&rfr_id=info%3Asid%2Fen.wikipedia.org%3AHelium+planet" class="Z3988"></span></span> </li> </ol></div></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=Helium_planet&action=edit&section=7" 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://arxiv.org/abs/1505.02221">Helium Atmospheres on Warm Neptune- and Sub-Neptune-Sized Exoplanets and Applications to GJ 436 b</a>, Renyu Hu, Sara Seager, Yuk L. Yung, 9 May 2015</li></ul> <div class="navbox-styles"><style data-mw-deduplicate="TemplateStyles:r1129693374">.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output .hlist dd,.mw-parser-output .hlist dt,.mw-parser-output .hlist li{margin:0;display:inline}.mw-parser-output .hlist.inline,.mw-parser-output .hlist.inline dl,.mw-parser-output .hlist.inline ol,.mw-parser-output .hlist.inline ul,.mw-parser-output .hlist dl dl,.mw-parser-output .hlist dl ol,.mw-parser-output .hlist dl ul,.mw-parser-output .hlist ol dl,.mw-parser-output .hlist ol ol,.mw-parser-output .hlist ol ul,.mw-parser-output .hlist ul dl,.mw-parser-output .hlist ul ol,.mw-parser-output .hlist ul ul{display:inline}.mw-parser-output .hlist .mw-empty-li{display:none}.mw-parser-output .hlist dt::after{content:": "}.mw-parser-output .hlist dd::after,.mw-parser-output .hlist li::after{content:" · ";font-weight:bold}.mw-parser-output .hlist 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.navbox-even{background-color:#f7f7f7}.mw-parser-output .navbox-odd{background-color:transparent}.mw-parser-output .navbox .hlist td dl,.mw-parser-output .navbox .hlist td ol,.mw-parser-output .navbox .hlist td ul,.mw-parser-output .navbox td.hlist dl,.mw-parser-output .navbox td.hlist ol,.mw-parser-output .navbox td.hlist ul{padding:0.125em 0}.mw-parser-output .navbox .navbar{display:block;font-size:100%}.mw-parser-output .navbox-title .navbar{float:left;text-align:left;margin-right:0.5em}body.skin--responsive .mw-parser-output .navbox-image img{max-width:none!important}@media print{body.ns-0 .mw-parser-output .navbox{display:none!important}}</style></div><div role="navigation" class="navbox" aria-labelledby="Exoplanets" style="padding:3px"><table class="nowraplinks hlist mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="3"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><style data-mw-deduplicate="TemplateStyles:r1239400231">.mw-parser-output .navbar{display:inline;font-size:88%;font-weight:normal}.mw-parser-output .navbar-collapse{float:left;text-align:left}.mw-parser-output .navbar-boxtext{word-spacing:0}.mw-parser-output .navbar ul{display:inline-block;white-space:nowrap;line-height:inherit}.mw-parser-output .navbar-brackets::before{margin-right:-0.125em;content:"[ "}.mw-parser-output .navbar-brackets::after{margin-left:-0.125em;content:" ]"}.mw-parser-output .navbar li{word-spacing:-0.125em}.mw-parser-output .navbar a>span,.mw-parser-output .navbar a>abbr{text-decoration:inherit}.mw-parser-output .navbar-mini abbr{font-variant:small-caps;border-bottom:none;text-decoration:none;cursor:inherit}.mw-parser-output .navbar-ct-full{font-size:114%;margin:0 7em}.mw-parser-output .navbar-ct-mini{font-size:114%;margin:0 4em}html.skin-theme-clientpref-night .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}@media(prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}}@media print{.mw-parser-output .navbar{display:none!important}}</style><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Exoplanet" title="Template:Exoplanet"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Exoplanet" title="Template talk:Exoplanet"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Exoplanet" title="Special:EditPage/Template:Exoplanet"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Exoplanets" style="font-size:114%;margin:0 4em">Exoplanets</div></th></tr><tr><td class="navbox-abovebelow" colspan="3"><div> <ul><li><a href="/wiki/Planet" title="Planet">Planet</a> <ul><li><a href="/wiki/Definition_of_planet" title="Definition of planet">Definition</a> <ul><li><a href="/wiki/IAU_definition_of_planet" title="IAU definition of planet">IAU</a></li></ul></li></ul></li> <li><a href="/wiki/Planetary_science" title="Planetary science">Planetary science</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;text-align:right;">Main topics</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/Exoplanet" title="Exoplanet">Exoplanet</a></li> <li><a href="/wiki/Exoplanet_orbital_and_physical_parameters" title="Exoplanet orbital and physical parameters">Exoplanet orbital and physical parameters</a></li> <li><a href="/wiki/Methods_of_detecting_exoplanets" title="Methods of detecting exoplanets">Methods of detecting exoplanets</a></li> <li><a href="/wiki/Planetary_system" title="Planetary system">Planetary system</a></li> <li><a href="/wiki/Planet-hosting_star" title="Planet-hosting star">Planet-hosting stars</a></li></ul> </div></td><td class="noviewer navbox-image" rowspan="10" style="width:1px;padding:0 0 0 2px"><div><span typeof="mw:File"><a href="/wiki/PDS_70" title="PDS 70"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/1/1c/PDS_70.jpg/100px-PDS_70.jpg" decoding="async" width="100" height="85" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/1c/PDS_70.jpg/150px-PDS_70.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/1c/PDS_70.jpg/200px-PDS_70.jpg 2x" data-file-width="2000" data-file-height="1692" /></a></span></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;text-align:right;">Sizes<br />and <br /><a href="/wiki/List_of_planet_types" title="List of planet types">types</a></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><th scope="row" class="navbox-group" style="width:1%;text-align:center;"><a href="/wiki/Terrestrial_planet" title="Terrestrial planet">Terrestrial</a></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/Carbon_planet" title="Carbon planet">Carbon planet</a></li> <li><a href="/wiki/Coreless_planet" title="Coreless planet">Coreless planet</a></li> <li><a href="/wiki/Desert_planet" title="Desert planet">Desert planet</a></li> <li><a href="/wiki/Dwarf_planet" title="Dwarf planet">Dwarf planet</a></li> <li><a href="/wiki/Hycean_planet" title="Hycean planet">Hycean planet</a></li> <li><a href="/wiki/Ice_planet" title="Ice planet">Ice planet</a></li> <li><a href="/wiki/Iron_planet" title="Iron planet">Iron planet</a> (Super-Mercury)</li> <li><a href="/wiki/Lava_planet" title="Lava planet">Lava planet</a></li> <li><a href="/wiki/Ocean_world" title="Ocean world">Ocean world</a></li> <li><a href="/wiki/Mega-Earth" title="Mega-Earth">Mega-Earth</a></li> <li><a href="/wiki/Sub-Earth" title="Sub-Earth">Sub-Earth</a></li> <li><a href="/wiki/Super-Earth" title="Super-Earth">Super-Earth</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;text-align:center;"><a href="/wiki/Gas_giant" title="Gas giant">Gaseous</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/Eccentric_Jupiter" title="Eccentric Jupiter">Eccentric Jupiter</a></li> <li><a href="/wiki/Mini-Neptune" title="Mini-Neptune">Mini-Neptune</a> (Gas dwarf)</li> <li><a class="mw-selflink selflink">Helium planet</a></li> <li><a href="/wiki/Hot_Jupiter" title="Hot Jupiter">Hot Jupiter</a></li> <li><a href="/wiki/Hot_Neptune" title="Hot Neptune">Hot Neptune</a></li> <li><a href="/wiki/Gas_giant" title="Gas giant">Gas giant</a></li> <li><a href="/wiki/Ice_giant" title="Ice giant">Ice giant</a></li> <li><a href="/wiki/Super-Jupiter" title="Super-Jupiter">Super-Jupiter</a></li> <li><a href="/wiki/Super-Neptune" title="Super-Neptune">Super-Neptune</a></li> <li><a href="/wiki/Super-puff" title="Super-puff">Super-puff</a></li> <li><a href="/wiki/Ultra-hot_Jupiter" class="mw-redirect" title="Ultra-hot Jupiter">Ultra-hot Jupiter</a></li> <li><a href="/wiki/Ultra-hot_Neptune" class="mw-redirect" title="Ultra-hot Neptune">Ultra-hot Neptune</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;text-align:center;">Other types</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/Blanet" title="Blanet">Blanet</a></li> <li><a href="/wiki/Brown_dwarf" title="Brown dwarf">Brown dwarf</a></li> <li><a href="/wiki/Chthonian_planet" title="Chthonian planet">Chthonian planet</a></li> <li><a href="/wiki/Circumbinary_planet" title="Circumbinary planet">Circumbinary planet</a></li> <li><a href="/wiki/Circumtriple_planet" title="Circumtriple planet">Circumtriple planet</a></li> <li><a href="/wiki/Disrupted_planet" title="Disrupted planet">Disrupted planet</a></li> <li><a href="/wiki/Double_planet" title="Double planet">Double planet</a></li> <li><a href="/wiki/Ecumenopolis" title="Ecumenopolis">Ecumenopolis</a></li> <li><a href="/wiki/Eyeball_planet" title="Eyeball planet">Eyeball planet</a></li> <li><a href="/wiki/Giant_planet" title="Giant planet">Giant planet</a></li> <li><a href="/wiki/Mesoplanet" title="Mesoplanet">Mesoplanet</a></li> <li><a href="/wiki/Planetary-mass_object" title="Planetary-mass object">Planemo</a></li> <li><a href="/wiki/Brown_dwarf#Low-mass_brown_dwarfs_versus_high-mass_planets" title="Brown dwarf">Planet/Brown dwarf boundary</a></li> <li><a href="/wiki/Planetesimal" title="Planetesimal">Planetesimal</a></li> <li><a href="/wiki/Protoplanet" title="Protoplanet">Protoplanet</a></li> <li><a href="/wiki/Pulsar_planet" title="Pulsar planet">Pulsar planet</a></li> <li><a href="/wiki/Sub-brown_dwarf" title="Sub-brown dwarf">Sub-brown dwarf</a></li> <li><a href="/wiki/Sub-Neptune" title="Sub-Neptune">Sub-Neptune</a></li> <li><a href="/wiki/Toroidal_planet" title="Toroidal planet">Toroidal planet</a></li> <li><a href="/wiki/Ultra-cool_dwarf" title="Ultra-cool dwarf">Ultra-cool dwarf</a></li> <li><a href="/wiki/Ultra-short_period_planet" title="Ultra-short period planet">Ultra-short period planet (USP)</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;text-align:right;"><a href="/wiki/Formation_and_evolution_of_the_Solar_System" title="Formation and evolution of the Solar System">Formation <br />and <br />evolution</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/Accretion_(astrophysics)" title="Accretion (astrophysics)">Accretion</a></li> <li><a href="/wiki/Accretion_disk" title="Accretion disk">Accretion disk</a></li> <li><a href="/wiki/Asteroid_belt" title="Asteroid belt">Asteroid belt</a></li> <li><a href="/wiki/Circumplanetary_disk" title="Circumplanetary disk">Circumplanetary disk</a></li> <li><a href="/wiki/Circumstellar_disc" title="Circumstellar disc">Circumstellar disc</a></li> <li><a href="/wiki/Circumstellar_envelope" title="Circumstellar envelope">Circumstellar envelope</a></li> <li><a href="/wiki/Cosmic_dust" title="Cosmic dust">Cosmic dust</a></li> <li><a href="/wiki/Debris_disk" title="Debris disk">Debris disk</a></li> <li><a href="/wiki/Detached_object" title="Detached object">Detached object</a></li> <li><a href="/wiki/Disrupted_planet" title="Disrupted planet">Disrupted planet</a></li> <li><a href="/wiki/Accretion_disk#Excretion_disk" title="Accretion disk">Excretion disk</a></li> <li><a href="/wiki/Exozodiacal_dust" title="Exozodiacal dust">Exozodiacal dust</a></li> <li><a href="/wiki/Extraterrestrial_materials" title="Extraterrestrial materials">Extraterrestrial materials</a></li> <li><a href="/wiki/Extraterrestrial_sample_curation" title="Extraterrestrial sample curation">Extraterrestrial sample curation</a></li> <li><a href="/wiki/Giant-impact_hypothesis" title="Giant-impact hypothesis">Giant-impact hypothesis</a></li> <li><a href="/wiki/Gravitational_collapse" title="Gravitational collapse">Gravitational collapse</a></li> <li><a href="/wiki/Hills_cloud" title="Hills cloud">Hills cloud</a></li> <li><a href="/wiki/Exoplanet_interiors" title="Exoplanet interiors">Internal structure</a></li> <li><a href="/wiki/Interplanetary_dust_cloud" title="Interplanetary dust cloud">Interplanetary dust cloud</a></li> <li><a href="/wiki/Interplanetary_medium" title="Interplanetary medium">Interplanetary medium</a></li> <li><a href="/wiki/Interplanetary_space" class="mw-redirect" title="Interplanetary space">Interplanetary space</a></li> <li><a href="/wiki/Interstellar_cloud" title="Interstellar cloud">Interstellar cloud</a></li> <li><a href="/wiki/Interstellar_dust" class="mw-redirect" title="Interstellar dust">Interstellar dust</a></li> <li><a href="/wiki/Interstellar_medium" title="Interstellar medium">Interstellar medium</a></li> <li><a href="/wiki/Outer_space#Interstellar_space" title="Outer space">Interstellar space</a></li> <li><a href="/wiki/Kuiper_belt" title="Kuiper belt">Kuiper belt</a></li> <li><a href="/wiki/List_of_interstellar_and_circumstellar_molecules" title="List of interstellar and circumstellar molecules">List of interstellar and circumstellar molecules</a></li> <li><a href="/wiki/Stellar_collision#Formation_of_planets" title="Stellar collision">Merging stars</a></li> <li><a href="/wiki/Molecular_cloud" title="Molecular cloud">Molecular cloud</a></li> <li><a href="/wiki/Nebular_hypothesis" title="Nebular hypothesis">Nebular hypothesis</a></li> <li><a href="/wiki/Oort_cloud" title="Oort cloud">Oort cloud</a></li> <li><a href="/wiki/Outer_space" title="Outer space">Outer space</a></li> <li><a href="/wiki/Planetary_migration" title="Planetary migration">Planetary migration</a></li> <li><a href="/wiki/Planetary_system" title="Planetary system">Planetary system</a></li> <li><a href="/wiki/Planetesimal" title="Planetesimal">Planetesimal</a></li> <li><a href="/wiki/Nebular_hypothesis#Formation_of_planets" title="Nebular hypothesis">Planet formation</a></li> <li><a href="/wiki/Protoplanetary_disk" title="Protoplanetary disk">Protoplanetary disk</a></li> <li><a href="/wiki/Ring_system" title="Ring system">Ring system</a></li> <li><a href="/wiki/Rubble_pile" title="Rubble pile">Rubble pile</a></li> <li><a href="/wiki/Sample-return_mission" title="Sample-return mission">Sample-return mission</a></li> <li><a href="/wiki/Scattered_disc" title="Scattered disc">Scattered disc</a></li> <li><a href="/wiki/Star_formation" title="Star formation">Star formation</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;text-align:right;"><a href="/wiki/Planetary_system" title="Planetary system">Systems</a></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/Exocomet" title="Exocomet">Exocomet</a> <ul><li><a href="/wiki/Interstellar_comet" class="mw-redirect" title="Interstellar comet">Interstellar</a></li></ul></li> <li><a href="/wiki/Exomoon" title="Exomoon">Exomoon</a> <ul><li><a href="/wiki/Tidally_detached_exomoon" title="Tidally detached exomoon">Tidally detached</a></li></ul></li> <li><a href="/wiki/Rogue_planet" title="Rogue planet">Rogue planet</a></li> <li>Orbits <ul><li><a href="/wiki/Retrograde_and_prograde_motion#Exoplanets" title="Retrograde and prograde motion">Retrograde</a></li> <li><a href="/wiki/Co-orbital_configuration#Trojans" title="Co-orbital configuration">Trojan</a></li> <li><a href="/wiki/Orbital_resonance#Mean-motion_resonances_among_extrasolar_planets" title="Orbital resonance">Mean-motion resonances</a></li> <li><a href="/wiki/Titius%E2%80%93Bode_law#Lunar_systems_and_other_planetary_systems" title="Titius–Bode law">Titius–Bode law</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;text-align:right;"><a href="/wiki/Planetary_system#Planet-hosting_stars" title="Planetary system">Host stars</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/A-type_main-sequence_star#Planets" title="A-type main-sequence star">A</a></li> <li><a href="/wiki/B-type_main-sequence_star#Planets" title="B-type main-sequence star">B</a></li> <li><a href="/wiki/Binary_star#Planets" title="Binary star">Binary star</a></li> <li><a href="/wiki/Brown_dwarf#Planets_around_brown_dwarfs" title="Brown dwarf">Brown dwarfs</a></li> <li><a href="/wiki/F-type_main-sequence_star#Planets" title="F-type main-sequence star">F/Yellow-white dwarfs</a></li> <li><a href="/wiki/G-type_main-sequence_star#Planets" title="G-type main-sequence star">G/Yellow dwarfs</a></li> <li><a href="/wiki/Herbig_Ae/Be_star#Planets" title="Herbig Ae/Be star">Herbig Ae/Be</a></li> <li><a href="/wiki/K-type_main-sequence_star#Planets" title="K-type main-sequence star">K/Orange dwarfs</a></li> <li><a href="/wiki/Red_dwarf#Planets" title="Red dwarf">M/Red dwarfs</a></li> <li><a href="/wiki/Pulsar_planet" title="Pulsar planet">Pulsar</a></li> <li><a href="/wiki/Red_giant#Planets" title="Red giant">Red giant</a></li> <li><a href="/wiki/Subdwarf_B_star#Planetary_systems" title="Subdwarf B star">Subdwarf B</a></li> <li><a href="/wiki/Subgiant#Planets" title="Subgiant">Subgiant</a></li> <li><a href="/wiki/T_Tauri_star#Planets" title="T Tauri star">T Tauri</a></li> <li><a href="/wiki/White_dwarf#Debris_disks_and_planets" title="White dwarf">White dwarfs</a></li> <li><a href="/wiki/Yellow_giant#Planets" class="mw-redirect" title="Yellow giant">Yellow giants</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;text-align:right;"><a href="/wiki/Methods_of_detecting_exoplanets" title="Methods of detecting exoplanets">Detection</a></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/Astrometry" title="Astrometry">Astrometry</a></li> <li><a href="/wiki/Methods_of_detecting_exoplanets#Direct_imaging" title="Methods of detecting exoplanets">Direct imaging</a> <ul><li><a href="/wiki/List_of_directly_imaged_exoplanets" title="List of directly imaged exoplanets">list</a></li></ul></li> <li><a href="/wiki/Gravitational_microlensing" title="Gravitational microlensing">Microlensing</a> <ul><li><a href="/wiki/List_of_exoplanets_detected_by_microlensing" title="List of exoplanets detected by microlensing">list</a></li></ul></li> <li><a href="/wiki/Polarimetry" title="Polarimetry">Polarimetry</a></li> <li><a href="/wiki/Methods_of_detecting_exoplanets#Pulsar_timing" title="Methods of detecting exoplanets">Timing</a> <ul><li><a href="/wiki/List_of_exoplanets_detected_by_timing" title="List of exoplanets detected by timing">list</a></li></ul></li> <li><a href="/wiki/Doppler_spectroscopy" title="Doppler spectroscopy">Radial velocity</a> <ul><li><a href="/wiki/List_of_exoplanets_detected_by_radial_velocity" title="List of exoplanets detected by radial velocity">list</a></li></ul></li> <li><a href="/wiki/Methods_of_detecting_exoplanets#Transit_photometry" title="Methods of detecting exoplanets">Transit method</a> <ul><li><a href="/wiki/List_of_transiting_exoplanets" title="List of transiting exoplanets">list</a></li></ul></li> <li><a href="/wiki/Transit-timing_variation" title="Transit-timing variation">Transit-timing variation</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;text-align:right;"><a href="/wiki/Planetary_habitability" title="Planetary habitability">Habitability</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/Astrobiology" title="Astrobiology">Astrobiology</a></li> <li><a href="/wiki/Astrooceanography" class="mw-redirect" title="Astrooceanography">Astrooceanography</a></li> <li><a href="/wiki/Circumstellar_habitable_zone" class="mw-redirect" title="Circumstellar habitable zone">Circumstellar habitable zone</a></li> <li><a href="/wiki/Earth_analog" title="Earth analog">Earth analog</a></li> <li><a href="/wiki/Extraterrestrial_liquid_water" title="Extraterrestrial liquid water">Extraterrestrial liquid water</a></li> <li><a href="/wiki/Galactic_habitable_zone" title="Galactic habitable zone">Galactic habitable zone</a></li> <li><a href="/wiki/Habitability_of_binary_star_systems" title="Habitability of binary star systems">Habitability of binary star systems</a></li> <li><a href="/wiki/Habitability_of_F-type_main-sequence_star_systems" title="Habitability of F-type main-sequence star systems">Habitability of F-type main-sequence star systems</a></li> <li><a href="/wiki/Habitability_of_K-type_main-sequence_star_systems" title="Habitability of K-type main-sequence star systems">Habitability of K-type main-sequence star systems</a></li> <li><a href="/wiki/Habitability_of_natural_satellites" title="Habitability of natural satellites">Habitability of natural satellites</a></li> <li><a href="/wiki/Habitability_of_neutron_star_systems" title="Habitability of neutron star systems">Habitability of neutron star systems</a></li> <li><a href="/wiki/Habitability_of_red_dwarf_systems" title="Habitability of red dwarf systems">Habitability of red dwarf systems</a></li> <li><a href="/wiki/Habitability_of_yellow_dwarf_systems" title="Habitability of yellow dwarf systems">Habitability of yellow dwarf systems</a></li> <li><a href="/wiki/Habitable_zone_for_complex_life" title="Habitable zone for complex life">Habitable zone for complex life</a></li> <li><a href="/wiki/List_of_potentially_habitable_exoplanets" title="List of potentially habitable exoplanets">List of potentially habitable exoplanets</a></li> <li><a href="/wiki/Tholin" title="Tholin">Tholin</a></li> <li><a href="/wiki/Superhabitable_planet" class="mw-redirect" title="Superhabitable planet">Superhabitable planet</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;text-align:right;">Catalogues</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/Catalog_of_Nearby_Habitable_Systems" title="Catalog of Nearby Habitable Systems">Nearby Habitable Systems</a></li> <li><a href="/wiki/Exoplanet_Data_Explorer" title="Exoplanet Data Explorer">Exoplanet Data Explorer</a></li> <li><a href="/wiki/Extrasolar_Planets_Encyclopaedia" title="Extrasolar Planets Encyclopaedia">Extrasolar Planets Encyclopaedia</a></li> <li><a href="/wiki/NASA_Exoplanet_Archive" title="NASA Exoplanet Archive">NASA Exoplanet Archive</a></li> <li><a href="/wiki/NASA_Star_and_Exoplanet_Database" title="NASA Star and Exoplanet Database">NASA Star and Exoplanet Database</a></li> <li><a href="/wiki/Open_Exoplanet_Catalogue" title="Open Exoplanet Catalogue">Open Exoplanet Catalogue</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;text-align:right;"><a href="/wiki/Lists_of_planets" title="Lists of planets">Lists</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>Exoplanetary systems <ul><li><a href="/wiki/List_of_exoplanetary_host_stars" class="mw-redirect" title="List of exoplanetary host stars">Host stars</a></li> <li><a href="/wiki/List_of_multiplanetary_systems" title="List of multiplanetary systems">Multiplanetary systems</a></li> <li><a href="/wiki/List_of_stars_with_proplyds" title="List of stars with proplyds">Stars with proto-planetary discs</a></li></ul></li></ul> <ul><li><a href="/wiki/Lists_of_exoplanets" class="mw-redirect" title="Lists of exoplanets">Exoplanets</a> <ul><li><a href="/wiki/Discoveries_of_exoplanets" title="Discoveries of exoplanets">Discoveries</a></li> <li><a href="/wiki/List_of_exoplanet_extremes" title="List of exoplanet extremes">Extremes</a></li> <li><a href="/wiki/List_of_exoplanet_firsts" title="List of exoplanet firsts">Firsts</a></li> <li><a href="/wiki/List_of_nearest_exoplanets" title="List of nearest exoplanets">Nearest</a></li> <li><a href="/wiki/List_of_largest_exoplanets" title="List of largest exoplanets">Largest</a></li> <li><a href="/wiki/List_of_most_massive_exoplanets" class="mw-redirect" title="List of most massive exoplanets">Heaviest</a></li> <li><a href="/wiki/List_of_nearest_terrestrial_exoplanet_candidates" title="List of nearest terrestrial exoplanet candidates">Terrestrial candidates</a></li> <li><a href="/wiki/List_of_exoplanets_discovered_by_the_Kepler_space_telescope" title="List of exoplanets discovered by the Kepler space telescope">Kepler</a> <ul><li><a href="/wiki/List_of_exoplanets_discovered_by_the_Kepler_space_telescope:_1%E2%80%93500" title="List of exoplanets discovered by the Kepler space telescope: 1–500">1–500</a></li> <li><a href="/wiki/List_of_exoplanets_discovered_by_the_Kepler_space_telescope:_501%E2%80%931000" title="List of exoplanets discovered by the Kepler space telescope: 501–1000">501–1000</a></li> <li><a href="/wiki/List_of_exoplanets_discovered_by_the_Kepler_space_telescope:_1001%E2%80%931500" title="List of exoplanets discovered by the Kepler space telescope: 1001–1500">1001–1500</a></li> <li><a href="/wiki/List_of_exoplanets_discovered_by_the_Kepler_space_telescope:_1501%E2%80%932000" title="List of exoplanets discovered by the Kepler space telescope: 1501–2000">1501–2000</a></li></ul></li> <li><a href="/wiki/List_of_exoplanets_observed_during_Kepler%27s_K2_mission" title="List of exoplanets observed during Kepler's K2 mission">K2</a></li> <li><a href="/wiki/List_of_potentially_habitable_exoplanets" title="List of potentially habitable exoplanets">Potentially habitable</a></li> <li><a href="/wiki/List_of_proper_names_of_exoplanets" title="List of proper names of exoplanets">Proper names</a></li></ul></li></ul> <ul><li>Discovered exoplanets by year <ul><li><a href="/wiki/List_of_exoplanets_discovered_before_2000" title="List of exoplanets discovered before 2000">before 2000</a></li> <li><a href="/wiki/List_of_exoplanets_discovered_between_2000%E2%80%932009" title="List of exoplanets discovered between 2000–2009">2000–2009</a></li> <li><a href="/wiki/List_of_exoplanets_discovered_in_2010" title="List of exoplanets discovered in 2010">2010</a></li> <li><a href="/wiki/List_of_exoplanets_discovered_in_2011" title="List of exoplanets discovered in 2011">2011</a></li> <li><a href="/wiki/List_of_exoplanets_discovered_in_2012" title="List of exoplanets discovered in 2012">2012</a></li> <li><a href="/wiki/List_of_exoplanets_discovered_in_2013" title="List of exoplanets discovered in 2013">2013</a></li> <li><a href="/wiki/List_of_exoplanets_discovered_in_2014" title="List of exoplanets discovered in 2014">2014</a></li> <li><a href="/wiki/List_of_exoplanets_discovered_in_2015" title="List of exoplanets discovered in 2015">2015</a></li> <li><a href="/wiki/List_of_exoplanets_discovered_in_2016" title="List of exoplanets discovered in 2016">2016</a></li> <li><a href="/wiki/List_of_exoplanets_discovered_in_2017" title="List of exoplanets discovered in 2017">2017</a></li> <li><a href="/wiki/List_of_exoplanets_discovered_in_2018" title="List of exoplanets discovered in 2018">2018</a></li> <li><a href="/wiki/List_of_exoplanets_discovered_in_2019" title="List of exoplanets discovered in 2019">2019</a></li> <li><a href="/wiki/List_of_exoplanets_discovered_in_2020" title="List of exoplanets discovered in 2020">2020</a></li> <li><a href="/wiki/List_of_exoplanets_discovered_in_2021" title="List of exoplanets discovered in 2021">2021</a></li> <li><a href="/wiki/List_of_exoplanets_discovered_in_2022" title="List of exoplanets discovered in 2022">2022</a></li> <li><a href="/wiki/List_of_exoplanets_discovered_in_2023" title="List of exoplanets discovered in 2023">2023</a></li> <li><a href="/wiki/List_of_exoplanets_discovered_in_2024" title="List of exoplanets discovered in 2024">2024</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;text-align:right;">Other</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/Carl_Sagan_Institute" title="Carl Sagan Institute">Carl Sagan Institute</a></li> <li><a href="/wiki/Exoplanet_naming_convention" title="Exoplanet naming convention">Exoplanet naming convention</a></li> <li><a href="/wiki/Phase_curve_(astronomy)#Exoplanets" title="Phase curve (astronomy)">Exoplanet phase curves</a></li> <li><a href="/wiki/Exoplanetary_Circumstellar_Environments_and_Disk_Explorer" title="Exoplanetary Circumstellar Environments and Disk Explorer">Exoplanetary Circumstellar Environments and Disk Explorer</a></li> <li><a href="/wiki/Extragalactic_planet" title="Extragalactic planet">Extragalactic planet</a></li> <li><a href="/wiki/Extrasolar_planets_in_fiction" title="Extrasolar planets in fiction">Extrasolar planets in fiction</a></li> <li><a href="/wiki/Geodynamics_of_terrestrial_exoplanets" title="Geodynamics of terrestrial exoplanets">Geodynamics of terrestrial exoplanets</a></li> <li><a href="/wiki/Neptunian_desert" title="Neptunian desert">Neptunian desert</a></li> <li><a href="/wiki/Nexus_for_Exoplanet_System_Science" title="Nexus for Exoplanet System Science">Nexus for Exoplanet System Science</a></li> <li><a href="/wiki/Globular_cluster#Planets" title="Globular cluster">Planets in globular clusters</a></li> <li><a href="/wiki/Small_planet_radius_gap" title="Small planet radius gap">Small planet radius gap</a></li> <li><a href="/wiki/Sudarsky%27s_gas_giant_classification" title="Sudarsky's gas giant classification">Sudarsky's gas giant classification</a></li></ul> </div></td></tr><tr><td class="navbox-abovebelow" colspan="3"><div> <ul><li><a href="/wiki/Discoveries_of_exoplanets" title="Discoveries of exoplanets">Discoveries of exoplanets</a></li> <li><a href="/wiki/List_of_exoplanet_search_projects" title="List of exoplanet search projects">Search projects</a></li></ul> </div></td></tr></tbody></table></div>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?type=1x1" alt="" width="1" height="1" style="border: none; position: absolute;"></noscript> <div class="printfooter" data-nosnippet="">Retrieved from "<a dir="ltr" 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