Iapetus | Britannica

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</div> </div> </div> <main> <div class="md-page-wrapper"> <div id="content" class="md-content"> <div class="grid gx-0 container-lg px-0 py-lg-20 mx-auto"> <div class="col-auto"> <div class="topic-left-rail md-article-drawer position-relative d-flex border-right-sm border-left-sm open"> <div class="drawer d-flex flex-column open"> <div class="left-rail-section-content"> <div class="topic-left-rail-header text-truncate bg-gray-50 position-relative text-right d-flex align-items-center"> <div class="tlr-title px-20 py-15 text-left"> <em class="material-icons text-gray-400 d-lg-none" data-icon="toc"></em> <a class="font-serif font-weight-bold text-black link-blue" href="https://www.britannica.com/topic/Iapetus-astronomy">Iapetus</a> </div> <button aria-label="Close" class="js-sections-close-button btn-link btn-sm btn d-lg-none position-absolute top-0 p-10 right-0" > <em class="material-icons font-26" data-icon="close"></em> </button> </div> <div class="section-content pl-10 pr-20 pl-sm-50 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other elements of the solar system, including asteroids, Kuiper belt, Oort cloud, comet" width="200" height="200" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/quiz/space-odyssey" >Space Odyssey</a> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/quiz/planets-and-the-earths-moon"> <img loading="lazy" src="https://cdn.britannica.com/74/166074-131-677298A0/Saturn-rings-planet-solar-system-Space-Art.jpg?w=200&h=200&c=crop" alt="Saturn. 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Hubbard</a> <div class="font-serif my-10"></div> </li> <li> <a href="/contributor/Bonnie-Buratti/8059292">Bonnie Buratti</a> <div class="font-serif my-10">Senior Research Scientist, Principal Scientist and Supervisor: Comets, Asteroids, and Satellites Group, NASA Jet Propulsion Laboratory, California Institute of Technology.</div> </li> </ul> <h3 class="topic-contributors-subtitle h4">Other Encyclopedia Britannica Contributors</h3> <ul class="list-unstyled mt-10 mb-20 contributor-NON_PRIMARY_EB"> <li> <a href="/editor/Erik-Gregersen/6723">Erik Gregersen</a> </li> <li> <a href="/editor/John-Higgins/7666587">John Higgins</a> </li> <li> <a href="/editor/Gloria-Lotha/7666594">Gloria Lotha</a> </li> <li> <a href="/editor/Chelsey-Parrott-Sheffer/6450">Chelsey Parrott-Sheffer</a> </li> <li> <a href="/editor/Grace-Young/7666614">Grace Young</a> </li> <li> <a href="/editor/The-Editors-of-Encyclopaedia-Britannica/4419">The Editors of Encyclopaedia Britannica</a> </li> </ul> </div> </div> <div id="history" class="pt-20 border-top"> <div id="history-Iapetus-astronomy"> <h2 class="mb-20">Article History</h2> <div class="mw-100 overflow-scroll"> <table class="article-history table"> <thead> <tr> <th class="topic-history-type">Type</th> <th class="topic-history-description">Description</th> <th class="topic-history-contributor">Contributor</th> <th class="topic-history-date">Date</th> </tr> </thead> <tbody> <tr> <td class="history-type"> <em class="material-icons " data-icon="link"></em> </td> <td> Modified link of Web site: The Nine Planets - Phobos.</td> <td class="history-contributor"> <ul class="list-unstyled"> <li data-type="contributor"> <a href="/editor/Gloria-Lotha/7666594">Gloria Lotha</a></li> </ul> </td> <td data-type="date" class="text-nowrap"> Jun 06, 2023</td> </tr> <tr> <td class="history-type"> <em class="material-icons " data-icon="link"></em> </td> <td> Add new Web site: National Aeronautics and Space Administration - Lapetus.</td> <td class="history-contributor"> <ul class="list-unstyled"> <li data-type="contributor"> <a href="/editor/Grace-Young/7666614">Grace Young</a></li> </ul> </td> <td data-type="date" class="text-nowrap"> Mar 11, 2016</td> </tr> <tr> <td class="history-type"> <em class="material-icons " data-icon="edit"></em> </td> <td> <span class="topic-history-diff-link link-blue" data-diff="/70/41870-009">Article revised and updated.</span></td> <td class="history-contributor"> <ul class="list-unstyled"> <li data-type="contributor"> <a href="/editor/Erik-Gregersen/6723">Erik Gregersen</a></li> <li data-type="contributor"> <a href="/contributor/Bonnie-Buratti/8059292">Bonnie Buratti</a></li> </ul> </td> <td data-type="date" class="text-nowrap"> Jan 24, 2011</td> </tr> <tr> <td class="history-type"> <em class="material-icons " data-icon="edit"></em> </td> <td> <span class="topic-history-diff-link link-blue" data-diff="/70/41870-008">Updated with information about the Phoebe dust ring.</span></td> <td class="history-contributor"> <ul class="list-unstyled"> <li data-type="contributor"> <a href="/editor/Erik-Gregersen/6723">Erik Gregersen</a></li> </ul> </td> <td data-type="date" class="text-nowrap"> Jan 07, 2010</td> </tr> <tr> <td class="history-type"> <em class="material-icons " data-icon="edit"></em> </td> <td> <span class="topic-history-diff-link link-blue" data-diff="/70/41870-007">Article revised and updated.</span></td> <td class="history-contributor"> <ul class="list-unstyled"> <li data-type="contributor"> <a href="/editor/Chelsey-Parrott-Sheffer/6450">Chelsey Parrott-Sheffer</a></li> </ul> </td> <td data-type="date" class="text-nowrap"> Mar 26, 2008</td> </tr> <tr> <td class="history-type"> <em class="material-icons " data-icon="edit"></em> </td> <td> <span class="topic-history-diff-link link-blue" data-diff="/70/41870-006">Added explanation of difference between two hemispheres.</span></td> <td class="history-contributor"> <ul class="list-unstyled"> <li data-type="contributor"> <a href="/editor/Erik-Gregersen/6723">Erik Gregersen</a></li> </ul> </td> <td data-type="date" class="text-nowrap"> Nov 14, 2007</td> </tr> <tr> <td class="history-type"> <em class="material-icons " data-icon="link"></em> </td> <td> Added new Web site: The Nine Planets - Phobos.</td> <td class="history-contributor"> <ul class="list-unstyled"> <li data-type="contributor"> <a href="/editor/John-Higgins/7666587">John Higgins</a></li> </ul> </td> <td data-type="date" class="text-nowrap"> Jun 08, 2006</td> </tr> <tr> <td class="history-type"> <em class="material-icons " data-icon="edit"></em> </td> <td> <span class="topic-history-diff-link link-blue" data-diff="/70/41870-002">Article revised and updated.</span></td> <td class="history-contributor"> <ul class="list-unstyled"> <li data-type="contributor"> <a href="/editor/The-Editors-of-Encyclopaedia-Britannica/4419">The Editors of Encyclopaedia Britannica</a></li> </ul> </td> <td data-type="date" class="text-nowrap"> May 11, 2006</td> </tr> <tr> <td class="history-type"> <em class="material-icons " data-icon="edit"></em> </td> <td> Article added to new online database.</td> <td class="history-contributor"> <ul class="list-unstyled"> <li data-type="contributor"> <a href="/editor/The-Editors-of-Encyclopaedia-Britannica/4419">The Editors of Encyclopaedia Britannica</a></li> </ul> </td> <td data-type="date" class="text-nowrap"> Jul 20, 1998</td> </tr> </tbody> </table> </div> <div id="md-topic-diff" class="d-none"> <div class="md-modal-header"> </div> <div class="md-modal-body"> <div class="md-topic-diff-header-container"> <div class="md-topic-diff-header"> <div class="grid"> <div class="col"> <div class="md-topic-diff-header-browse"> <span>View Changes: </span> <div title="previous change" id="md-topic-diff-previous" class="md-topic-diff-pn disabled"></div> <div title="next change" id="md-topic-diff-next" class="md-topic-diff-pn"></div> </div> </div> <div class="col justify-content-center d-flex align-items-center align-self-center"> <div class="h3">Article History</div> </div> <div class="col"> <div class="md-topic-diff-header-info"> <div>Revised: <span id="md-topic-diff-date"></span></div> <div>By: <span id="md-topic-diff-contributor"></span></div> </div> <em class="md-close material-icons" data-icon="close"></em> </div> </div> </div> </div> <div id="md-topic-diff-container" class="md-overlay-container mt-50 mt-sm-0"></div> </div> </div> </div> </div> </div> </div> </div> <aside class="col-md-da-320"></aside> </div> </div> </div> </div></div> </div> </main> <div id="md-footer"></div> <footer class="md-footer footer-wrapper hide-on-edit"> <div class="footer-bck"> <DIV class="marketing-FOOTER_NEWSLETTER marketing-content" data-marketing-id="FOOTER_NEWSLETTER"><div class="md-footer-newsletter-form pt-10 mb-30 mx-15 mx-sm-120"> <div class="font-18"> <strong>History at your fingertips –</strong> Sign up here to see what happened On This Day, every day in your inbox! </div> <div class="p-30"> <div class="newsletter-form-container"> <form class="newsletter-form" method="post" action="/newsletter-subscription/EB_ON_THIS_DAY"> <div class="form-group grid d-flex justify-content-center"> <div class="col-sm-50 col-100"> <label class="sr-only" for="enter-your-email">Enter your email</label> <input id="enter-your-email" type="email" name="email" class="form-control font-18 p-10" placeholder="Enter your email" pattern="[a-z0-9._%+-]+@[a-z0-9.-]+\.[a-z]{2,4}$" required> </div> <div class="col-sm-auto col-100 mt-5 mt-sm-0"> <button type="submit" class="btn btn-outline-white" style="width: 100%; height:100%;">Subscribe</button> </div> </div> <div class="text-white pt-30 text-opacity"> By signing up for this email, you are agreeing to news, offers, and information from Encyclopaedia Britannica.<br> Click here to view our <a class="link-white text-decoration-underline" href="https://corporate.britannica.com/privacy-policy2" target="_blank" rel="noopener nofollow">Privacy Notice</a>. 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Iapetus | Britannica