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Coupled Orbital and Thermal Evolution of Ganymede - NASA/ADS
<!DOCTYPE html> <!--[if lt IE 7]> <html class="no-js lt-ie9 lt-ie8 lt-ie7"> <![endif]--> <!--[if IE 7]> <html class="no-js lt-ie9 lt-ie8"> <![endif]--> <!--[if IE 8]> <html class="no-js lt-ie9"> <![endif]--> <!--[if gt IE 8]><!--> <html class="no-js" lang="en"> <!--<![endif]--> <head> <title>Coupled Orbital and Thermal Evolution of Ganymede - NASA/ADS</title> <!-- favicon --> <link rel="apple-touch-icon" sizes="180x180" href="//styles/favicon/apple-touch-icon.png" /> <link rel="icon" type="image/png" sizes="32x32" href="//styles/favicon/favicon-32x32.png" /> <link rel="icon" type="image/png" sizes="16x16" href="//styles/favicon/favicon-16x16.png" /> <link rel="manifest" href="//styles/favicon/site.webmanifest" /> <link rel="mask-icon" href="//styles/favicon/safari-pinned-tab.svg" color="#5bbad5" /> <meta name="apple-mobile-web-app-title" content="NASA ADS" /> <meta name="application-name" content="NASA ADS" /> <meta name="msapplication-TileColor" content="#ffc40d" /> <meta name="theme-color" content="#ffffff" /> <!-- /favicon --> <link rel="stylesheet" href="/styles/css/styles.css"> <meta name="robots" content="noarchive"> <link rel="canonical" href="http://ui.adsabs.harvard.edu/abs/1997Icar..129..367S/abstract"/> <meta name="description" content="We explore the hypothesis that passage through an eccentricity-pumping resonance could lead to the resurfacing of Ganymede. To do so, we couple R. Malhotra's (1991,Icarus94,399-412) orbital model for the tidal evolution of the Laplace resonance to an internal model of Ganymede. Our model explores the conditions under which Ganymede can undergo global thermal runaway, assuming that theQ/kof Ganymede is strongly dependent on internal temperature. (HereQis the tidal dissipation function andkis the second-degree Love number.) We allow the system to pass through the ω<SUB>1</SUB>/ω<SUB>2</SUB>≈ 2 or ω<SUB>1</SUB>/ω<SUB>2</SUB>≈ 1/2 resonance, where ω<SUB>1</SUB>≡ 2n<SUB>2</SUB>-n<SUB>1</SUB>, ω<SUB>2</SUB>≡ 2n<SUB>3</SUB>-n<SUB>2</SUB>, andn<SUB>1</SUB>,n<SUB>2</SUB>, andn<SUB>3</SUB>are the mean motions of Io, Europa, and Ganymede. If Ganymede's initial internal temperature is either “too hot” or “too cold,” no runaway occurs, while for intermediate temperatures (∼200 K in the upper mantle), conditions are “just right,” and runaway occurs. The range of mantle temperatures that allows runaway depends on the model for tidalQ; we use the Maxwell model, which tiesQto the creep viscosity of ice. Runaways can induce up to ∼50-100 K warming and formation of a large internal ocean; they occur over a 10<SUP>7</SUP>to 10<SUP>8</SUP>-year period. Assuming carbonaceous chondritic abundances of radionuclides in Ganymede's rocky portion, however, we find that the interior cannot cool to the initial temperatures needed to allow large runaways. If our model is correct, large runaways cannot occur, although small runaways are still possible. Different formulations of tidalQor convective cooling may allow large runaways. Large runaways are also possible if radionuclides are substantially depleted, although this is unlikely. <P />We next consider the consequences of a large runaway, assuming it can occur. Ganymede can undergo 0.5% thermal expansion (by volume) during the largest thermal runaways. Melting of the ice mantle provides up to 2% expansion despite the fact that contraction produced by melting ice I offsets expansion produced by melting high-pressure ice phases. Solid-solid phase transitions cause negligible satellite expansion. Lithospheric stresses caused by expansion of 2% over 10<SUP>7</SUP>to 10<SUP>8</SUP>years are ∼10<SUP>2</SUP>bars at the surface, and drop to a few bars at several kilometers depth. Such stresses could cause cracking to depths of several kilometers. The cracking and near-surface production of warm or partially molten ice make resurfacing a plausible outcome of a large thermal runaway. The tidal heating events proposed here may also be relevant for generation of Ganymede's modern-day magnetic field."> <!-- Open Graph --> <meta property="og:type" content="article"> <meta property="og:title" content="Coupled Orbital and Thermal Evolution of Ganymede"> <meta property="og:site_name" content="NASA/ADS"> <meta property="og:description" content="We explore the hypothesis that passage through an eccentricity-pumping resonance could lead to the resurfacing of Ganymede. To do so, we couple R. Malhotra's (1991,Icarus94,399-412) orbital model for the tidal evolution of the Laplace resonance to an internal model of Ganymede. Our model explores the conditions under which Ganymede can undergo global thermal runaway, assuming that theQ/kof Ganymede is strongly dependent on internal temperature. (HereQis the tidal dissipation function andkis the second-degree Love number.) We allow the system to pass through the ω<SUB>1</SUB>/ω<SUB>2</SUB>≈ 2 or ω<SUB>1</SUB>/ω<SUB>2</SUB>≈ 1/2 resonance, where ω<SUB>1</SUB>≡ 2n<SUB>2</SUB>-n<SUB>1</SUB>, ω<SUB>2</SUB>≡ 2n<SUB>3</SUB>-n<SUB>2</SUB>, andn<SUB>1</SUB>,n<SUB>2</SUB>, andn<SUB>3</SUB>are the mean motions of Io, Europa, and Ganymede. If Ganymede's initial internal temperature is either “too hot” or “too cold,” no runaway occurs, while for intermediate temperatures (∼200 K in the upper mantle), conditions are “just right,” and runaway occurs. The range of mantle temperatures that allows runaway depends on the model for tidalQ; we use the Maxwell model, which tiesQto the creep viscosity of ice. Runaways can induce up to ∼50-100 K warming and formation of a large internal ocean; they occur over a 10<SUP>7</SUP>to 10<SUP>8</SUP>-year period. Assuming carbonaceous chondritic abundances of radionuclides in Ganymede's rocky portion, however, we find that the interior cannot cool to the initial temperatures needed to allow large runaways. If our model is correct, large runaways cannot occur, although small runaways are still possible. Different formulations of tidalQor convective cooling may allow large runaways. Large runaways are also possible if radionuclides are substantially depleted, although this is unlikely. <P />We next consider the consequences of a large runaway, assuming it can occur. Ganymede can undergo 0.5% thermal expansion (by volume) during the largest thermal runaways. Melting of the ice mantle provides up to 2% expansion despite the fact that contraction produced by melting ice I offsets expansion produced by melting high-pressure ice phases. Solid-solid phase transitions cause negligible satellite expansion. Lithospheric stresses caused by expansion of 2% over 10<SUP>7</SUP>to 10<SUP>8</SUP>years are ∼10<SUP>2</SUP>bars at the surface, and drop to a few bars at several kilometers depth. Such stresses could cause cracking to depths of several kilometers. The cracking and near-surface production of warm or partially molten ice make resurfacing a plausible outcome of a large thermal runaway. The tidal heating events proposed here may also be relevant for generation of Ganymede's modern-day magnetic field."> <meta property="og:url" content="https://ui.adsabs.harvard.edu/abs/1997Icar..129..367S/abstract"> <meta property="og:image" content="https://ui.adsabs.harvard.edu/styles/img/transparent_logo.svg"> <meta property="article:published_time" content="10/1997"> <meta property="article:author" content="Showman, Adam P."> <meta property="article:author" content="Stevenson, David J."> <meta property="article:author" content="Malhotra, Renu"> <!-- citation_* --> <meta name="citation_journal_title" content="Icarus"> <meta name="citation_authors" content="Showman, Adam P.;Stevenson, David J.;Malhotra, Renu"> <meta name="citation_title" content="Coupled Orbital and Thermal Evolution of Ganymede"> <meta name="citation_date" content="10/1997"> <meta name="citation_volume" content="129"> <meta name="citation_issue" content="2"> <meta name="citation_firstpage" content="367"> <meta name="citation_doi" content="10.1006/icar.1997.5778"> <meta name="citation_issn" content="0019-1035"> <meta name="citation_language" content="en"> <meta name="citation_abstract_html_url" content="https://ui.adsabs.harvard.edu/abs/1997Icar..129..367S/abstract"> <meta name="citation_publication_date" content="10/1997"> <meta name="citation_lastpage" content="383" /> <link title="schema(PRISM)" rel="schema.prism" href="http://prismstandard.org/namespaces/1.2/basic/" /> <meta name="prism.publicationDate" content="10/1997" /> <meta name="prism.publicationName" content="Icar" /> <meta name="prism.issn" content="0019-1035" /> <meta name="prism.volume" content="129" /> <meta name="prism.startingPage" content="367" /> <meta name="prism.endingPage" content="383" /> <link title="schema(DC)" rel="schema.dc" href="http://purl.org/dc/elements/1.1/" /> <meta name="dc.identifier" content="doi:10.1006/icar.1997.5778" /> <meta name="dc.date" content="10/1997" /> <meta name="dc.source" content="Icar" /> <meta name="dc.title" content="Coupled Orbital and Thermal Evolution of Ganymede" /> <meta name="dc.creator" content="Showman, Adam P."> <meta name="dc.creator" content="Stevenson, David J."> <meta name="dc.creator" content="Malhotra, Renu"> <!-- twitter card --> <meta name="twitter:card" content="summary_large_image"/> <meta name="twitter:description" content="We explore the hypothesis that passage through an eccentricity-pumping resonance could lead to the resurfacing of Ganymede. To do so, we couple R. Malhotra's (1991,Icarus94,399-412) orbital model for the tidal evolution of the Laplace resonance to an internal model of Ganymede. Our model explores the conditions under which Ganymede can undergo global thermal runaway, assuming that theQ/kof Ganymede is strongly dependent on internal temperature. (HereQis the tidal dissipation function andkis the second-degree Love number.) We allow the system to pass through the ω<SUB>1</SUB>/ω<SUB>2</SUB>≈ 2 or ω<SUB>1</SUB>/ω<SUB>2</SUB>≈ 1/2 resonance, where ω<SUB>1</SUB>≡ 2n<SUB>2</SUB>-n<SUB>1</SUB>, ω<SUB>2</SUB>≡ 2n<SUB>3</SUB>-n<SUB>2</SUB>, andn<SUB>1</SUB>,n<SUB>2</SUB>, andn<SUB>3</SUB>are the mean motions of Io, Europa, and Ganymede. If Ganymede's initial internal temperature is either “too hot” or “too cold,” no runaway occurs, while for intermediate temperatures (∼200 K in the upper mantle), conditions are “just right,” and runaway occurs. The range of mantle temperatures that allows runaway depends on the model for tidalQ; we use the Maxwell model, which tiesQto the creep viscosity of ice. Runaways can induce up to ∼50-100 K warming and formation of a large internal ocean; they occur over a 10<SUP>7</SUP>to 10<SUP>8</SUP>-year period. Assuming carbonaceous chondritic abundances of radionuclides in Ganymede's rocky portion, however, we find that the interior cannot cool to the initial temperatures needed to allow large runaways. If our model is correct, large runaways cannot occur, although small runaways are still possible. Different formulations of tidalQor convective cooling may allow large runaways. Large runaways are also possible if radionuclides are substantially depleted, although this is unlikely. <P />We next consider the consequences of a large runaway, assuming it can occur. Ganymede can undergo 0.5% thermal expansion (by volume) during the largest thermal runaways. Melting of the ice mantle provides up to 2% expansion despite the fact that contraction produced by melting ice I offsets expansion produced by melting high-pressure ice phases. Solid-solid phase transitions cause negligible satellite expansion. Lithospheric stresses caused by expansion of 2% over 10<SUP>7</SUP>to 10<SUP>8</SUP>years are ∼10<SUP>2</SUP>bars at the surface, and drop to a few bars at several kilometers depth. Such stresses could cause cracking to depths of several kilometers. The cracking and near-surface production of warm or partially molten ice make resurfacing a plausible outcome of a large thermal runaway. The tidal heating events proposed here may also be relevant for generation of Ganymede's modern-day magnetic field."/> <meta name="twitter:title" content="Coupled Orbital and Thermal Evolution of Ganymede"/> <meta name="twitter:site" content="@adsabs"/> <meta name="twitter:domain" content="NASA/ADS"/> <meta name="twitter:image:src" content="https://ui.adsabs.harvard.edu/styles/img/transparent_logo.svg"/> <meta name="twitter:creator" content="@adsabs"/> <meta charset="utf-8"> <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no"> <base href="/"> <style> .btn-full-ads { color: #fff !important; background-color: #1a1a1a !important; border-color: #1a1a1a !important; margin-top: 9px !important; padding-bottom: 10px !important; padding-top: 10px !important; } .btn-full-ads:hover, .btn-full-ads:focus, .btn-full-ads:active, .btn-full-ads.active, .open>.dropdown-toggle.btn-full-ads { color: #000 !important; background-color: #ddd !important; border-color: #1a1a1a !important; 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<li class="author"><a href="/search/?q=author%3A%22Stevenson%2C+David+J.%22">Stevenson, David J.</a> </li>; <li class="author"><a href="/search/?q=author%3A%22Malhotra%2C+Renu%22">Malhotra, Renu</a> </li> </ul> </div> <div class="s-abstract-text"> <h4 class="sr-only">Abstract</h4> <p> We explore the hypothesis that passage through an eccentricity-pumping resonance could lead to the resurfacing of Ganymede. To do so, we couple R. Malhotra's (1991,Icarus94,399-412) orbital model for the tidal evolution of the Laplace resonance to an internal model of Ganymede. Our model explores the conditions under which Ganymede can undergo global thermal runaway, assuming that theQ/kof Ganymede is strongly dependent on internal temperature. (HereQis the tidal dissipation function andkis the second-degree Love number.) We allow the system to pass through the ω<SUB>1</SUB>/ω<SUB>2</SUB>≈ 2 or ω<SUB>1</SUB>/ω<SUB>2</SUB>≈ 1/2 resonance, where ω<SUB>1</SUB>≡ 2n<SUB>2</SUB>-n<SUB>1</SUB>, ω<SUB>2</SUB>≡ 2n<SUB>3</SUB>-n<SUB>2</SUB>, andn<SUB>1</SUB>,n<SUB>2</SUB>, andn<SUB>3</SUB>are the mean motions of Io, Europa, and Ganymede. If Ganymede's initial internal temperature is either “too hot” or “too cold,” no runaway occurs, while for intermediate temperatures (∼200 K in the upper mantle), conditions are “just right,” and runaway occurs. The range of mantle temperatures that allows runaway depends on the model for tidalQ; we use the Maxwell model, which tiesQto the creep viscosity of ice. Runaways can induce up to ∼50-100 K warming and formation of a large internal ocean; they occur over a 10<SUP>7</SUP>to 10<SUP>8</SUP>-year period. Assuming carbonaceous chondritic abundances of radionuclides in Ganymede's rocky portion, however, we find that the interior cannot cool to the initial temperatures needed to allow large runaways. If our model is correct, large runaways cannot occur, although small runaways are still possible. Different formulations of tidalQor convective cooling may allow large runaways. Large runaways are also possible if radionuclides are substantially depleted, although this is unlikely. <P />We next consider the consequences of a large runaway, assuming it can occur. Ganymede can undergo 0.5% thermal expansion (by volume) during the largest thermal runaways. Melting of the ice mantle provides up to 2% expansion despite the fact that contraction produced by melting ice I offsets expansion produced by melting high-pressure ice phases. Solid-solid phase transitions cause negligible satellite expansion. Lithospheric stresses caused by expansion of 2% over 10<SUP>7</SUP>to 10<SUP>8</SUP>years are ∼10<SUP>2</SUP>bars at the surface, and drop to a few bars at several kilometers depth. Such stresses could cause cracking to depths of several kilometers. The cracking and near-surface production of warm or partially molten ice make resurfacing a plausible outcome of a large thermal runaway. The tidal heating events proposed here may also be relevant for generation of Ganymede's modern-day magnetic field. </p> </div> <br> <dl class="s-abstract-dl-horizontal"> <dt>Publication:</dt> <dd> <div id="article-publication">Icarus</div> </dd> <dt>Pub Date:</dt> <dd>October 1997</dd> <dt>DOI:</dt> <dd> <span> <a href="/link_gateway/1997Icar..129..367S/doi:10.1006/icar.1997.5778" target="_blank" rel="noopener">10.1006/icar.1997.5778</a> <i class="fa fa-external-link"></i> </span> </dd> <dt>Bibcode:</dt> <dd> <a href="/abs/1997Icar..129..367S/abstract"> 1997Icar..129..367S </a> <i class="icon-help" title="The bibcode is assigned by the ADS as a unique identifier for the paper."></i> </dd> </dl> </article> </div> <div data-widget="ShowCitations"></div> <div data-widget="ShowReferences"></div> <div data-widget="ShowCoreads"></div> <div data-widget="ShowSimilar"></div> <div data-widget="ShowTableofcontents"></div> <div data-widget="ShowGraphics"></div> <div data-widget="ShowExportcitation" data-origin="abstract"></div> <div data-widget="ShowMetrics" data-allow-redirect="false"></div> <div data-widget="MetaTagsWidget"></div> </div> </div> </div> <div class="s-right-col-container col-xs-12 col-sm-12 col-md-3 col-lg-2 s-right-column" id="right-col-container" > <div data-widget="ShowResources"> <div data-reactroot="" class="s-right-col-widget-container" style="padding: 10px" > <div> <div class="resources__container"> <div class="resources__full__list"> <div class="resources__header__row"> <i class="fa fa-file-text-o" aria-hidden="true"> </i> <div class="resources__header__title">full text sources</div> </div> <div class="resources__content"> <div class="resources__content__title">Publisher</div> <div class="resources__content__links"> <span> <div class="resources__content__link__separator">|</div> </span> <span> <a href="/link_gateway/1997Icar..129..367S/PUB_HTML" rel="noopener" class="resources__content__link " > <i class="fa fa-file-text" aria-hidden="true"> </i> </a> </span> </div> </div> </div> </div> <div data-widget="ShowAssociated"> </div> </div> </div> </div> <div data-widget="ShowGraphicsSidebar"> </div> </div> </div> </div> </div> </div> </div> <div id="footer-container"> <div data-widget="FooterWidget"> <div class="footer s-footer"> <footer> <div class="__footer_wrapper"> <div class="__footer_brand"> © The SAO/NASA Astrophysics Data System <div class="__footer_brand_extra"> <p> <i class="fa fa-envelope"></i> adshelp[at]cfa.harvard.edu </p> <p> The ADS is operated by the Smithsonian Astrophysical Observatory under NASA Cooperative Agreement <em>NNX16AC86A</em> </p> </div> <div class="__footer_brand_logos"> <a href="http://www.nasa.gov" target="_blank" rel="noopener"> <img src="/styles/img/nasa.svg" alt="NASA logo" id="nasa-logo"> </a> <a href="http://www.si.edu" target="_blank" rel="noopener"> <img id="smithsonian-logo" src="/styles/img/smithsonian.svg" alt="Smithsonian logo"> </a> <a href="https://www.cfa.harvard.edu/" target="_blank" rel="noopener"> <img src="/styles/img/cfa.png" title="Harvard Center for Astrophysics logo" id="cfa-logo"> </a> </div> </div> <div class="__footer_list"> <div class="__footer_list_title"> Resources </div> <ul class="__footer_links"> <li> <a href="/about/" target="_blank" rel="noopener"> <i class="fa fa-question-circle"></i> About ADS </a> </li> <li> <a href="//ui.adsabs.harvard.edu/help/" target="_blank" rel="noopener"> <i class="fa fa-info-circle"></i> ADS Help </a> </li> <li> <a href="//ui.adsabs.harvard.edu/help/whats_new/" target="_blank" rel="noopener"> <i class="fa fa-bullhorn"></i> What's New </a> </li> <li> <a href="/about/careers/" target="_blank" rel="noopener"> <i class="fa fa-group"></i> Careers@ADS </a> </li> </ul> </div> <div class="__footer_list"> <div class="__footer_list_title"> Social </div> <ul class="__footer_links"> <li> <a href="//twitter.com/adsabs" target="_blank" rel="noopener"> <i class="fa fa-twitter"></i> @adsabs </a> </li> <li> <a href="//ui.adsabs.harvard.edu/blog/" target="_blank" rel="noopener"> <i class="fa fa-newspaper-o"></i> ADS Blog </a> </li> </ul> </div> <div class="__footer_list"> <div class="__footer_list_title"> Project </div> <ul class="__footer_links"> <li> <a href="/core/never">Switch to full ADS</a> </li> <li> <a href="https://adsisdownorjustme.herokuapp.com/" target="_blank" rel="noopener">Is ADS down? 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