A Modern Dynamo as a Consequence of Triton’s Capture at Neptune

A Modern Dynamo as a Consequence of Triton’s Capture at Neptune | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article A Modern Dynamo as a Consequence of Triton’s Capture at Neptune Lana Tilke, Kevin Trinh, Joseph O'Rourke This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7330969/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted You are reading this latest preprint version Abstract Triton, Neptune’s largest moon, is one of the highest-priority candidate ocean worlds to explore. Its capture and orbital circularization may have caused intense heating that led to internal differentiation and the formation of a metallic core. In this work, we argue that this “hot start” may lead to Triton hosting an active dynamo today, driven by ongoing convection within its metallic core. Using thermal evolution models, we explore three potential regimes of core crystallization to assess their impact on the likelihood of dynamo action. Our results imply that Triton, like Ganymede, may possess an ongoing dynamo that generates a magnetic field with field strengths on the order of ~1 μT at the surface. If confirmed, the existence of a dynamo would provide a unique constraint on Triton’s internal structure, composition, capture history, and evolution. Strong dynamo fields, however, would also complicate efforts to characterize the subsurface ocean via magnetometry. Physical sciences/Astronomy and planetary science/Planetary science/Geodynamics Physical sciences/Astronomy and planetary science/Planetary science/Rings and moons Full Text Additional Declarations There is NO Competing Interest. Cite Share Download PDF Status: Under Review Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7330969","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":504225208,"identity":"60f4f11b-3bfe-4480-9b0f-be8bc941a29f","order_by":0,"name":"Lana Tilke","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAApElEQVRIiWNgGAWjYBACPgbGxoMNDDYQHg8xWtjYGBuAWtJI0sLAANRymBQt8s0NB2dUnJeXn5HA+OBtG7EO23DmtuGGGwnMhnOJ1vKw7TbjBokENmle4rX8O2c/f0YC+2/itWxsOJDYcCOBjZlILYlA7x9LTt5w5mGz5JxzRGjhZz7+8GFPjZ3t/Pbkgx/elBGhBQkwNpCmfhSMglEwCkYBbgAAC/o5FMXnmwsAAAAASUVORK5CYII=","orcid":"https://orcid.org/0000-0001-7541-074X","institution":"Arizona State University","correspondingAuthor":true,"prefix":"","firstName":"Lana","middleName":"","lastName":"Tilke","suffix":""},{"id":504225209,"identity":"71b23b05-5840-4173-8f7d-510a0bab1e75","order_by":1,"name":"Kevin Trinh","email":"","orcid":"","institution":"California Institute of Technology","correspondingAuthor":false,"prefix":"","firstName":"Kevin","middleName":"","lastName":"Trinh","suffix":""},{"id":504225210,"identity":"b93948d8-9ef8-4593-8dbc-27758253f366","order_by":2,"name":"Joseph O'Rourke","email":"","orcid":"https://orcid.org/0000-0002-1180-996X","institution":"Arizona State University","correspondingAuthor":false,"prefix":"","firstName":"Joseph","middleName":"","lastName":"O'Rourke","suffix":""}],"badges":[],"createdAt":"2025-08-09 03:20:29","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7330969/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7330969/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":89805132,"identity":"29584423-6149-4c8d-81d3-ed85d37eafa3","added_by":"auto","created_at":"2025-08-25 08:57:51","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1073147,"visible":true,"origin":"","legend":"Article File","description":"","filename":"TritonDynamoNatureAstronomyFINAL.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7330969/v1_covered_8ffd47b0-533e-45a9-8024-48e44bf252c5.pdf"}],"financialInterests":"There is \u003cb\u003eNO\u003c/b\u003e Competing Interest.","formattedTitle":"A Modern Dynamo as a Consequence of Triton’s Capture at Neptune","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"nature-portfolio","isNatureJournal":true,"hasQc":false,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"","title":"Nature Portfolio","twitterHandle":"","acdcEnabled":false,"dfaEnabled":false,"editorialSystem":"ejp","reportingPortfolio":"","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-7330969/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7330969/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"Triton, Neptune’s largest moon, is one of the highest-priority candidate ocean worlds to explore. 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