Los Alamos | Atomic Research, Nuclear Weapons, Manhattan Project

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They write new content and verify and edit content received from contributors.</div> </a> <div data-popper-arrow></div> </div> <span class="btn btn-link editor-link p-0 qa-byline-link gtm-byline font-12 byline-contributor text-decoration-underline"> The Editors of Encyclopaedia Britannica</span></div> <div class="last-updated font-12 font-serif"> <a class="byline-edit-history" href="https://www.britannica.com/place/Los-Alamos-New-Mexico/additional-info#history" rel="nofollow">Article History</a> </div></div> </div> <button class="d-flex d-lg-none btn btn-outline-blue border rounded-sm shadow-sm mobile-toc-button gtm-mobile-toc-inline-button d-none d-sm-block js-sections-inline-button module-spacing btn d-lg-none"> <em class="material-icons mr-5 ml-n10 my-n5 md-icon" data-icon="toc"></em> Table of Contents </button> <div class="d-flex d-sm-none flex-row"> <button class="d-flex d-lg-none btn btn-outline-blue border rounded-sm shadow-sm mobile-toc-button gtm-mobile-toc-inline-button js-sections-inline-button module-spacing"> <em class="material-icons mr-5 ml-n10 my-n5 md-icon" data-icon="toc"></em> Table of Contents </button> <button class="ai-ask-button btn border-2 ai-ask-button btn border-2 module-spacing btn-sm js-inline-ai-ask-button btn-outline-red-400 border-red-400 p-10 ml-5"> Ask the Chatbot a Question </button> </div> <span class="marker before-article"></span><section data-level="1" id="ref1"><span class="marker PREMOD1 mod-inline"></span><p class="topic-paragraph"><strong><span id="ref102060"></span>Los Alamos</strong>, city, seat (1949) of Los Alamos county, north-central <a href="https://www.britannica.com/place/New-Mexico" class="md-crosslink " data-show-preview="true">New Mexico</a>, U.S. It lies on the <span id="ref102061"></span>Pajarito Plateau (elevation 7,300 feet [2,225 metres]) of the Jemez Mountains, 35 miles (56 km) northwest of <a href="https://www.britannica.com/place/Santa-Fe-New-Mexico" class="md-crosslink " data-show-preview="true">Santa Fe</a>. The site was named Los Alamos (Spanish: “the cottonwoods”) by <span id="ref102062"></span>Ashley Pond, founder of the Los Alamos Ranch School for Boys (1918–43).</p><span class="marker MOD1 mod-inline"></span><span class="marker PREMOD2 mod-inline"></span><p class="topic-paragraph">In 1942 Los Alamos was chosen by the U.S. government (because of its <a class="md-dictionary-link md-dictionary-tt-off eb" data-term="comparative" href="https://www.britannica.com/dictionary/comparative" data-type="EB">comparative</a> isolation and natural facilities) as the location for the Atomic Research Laboratory, then known as the <span id="ref102063"></span><a href="https://www.britannica.com/event/Manhattan-Project" class="md-crosslink " data-show-preview="true">Manhattan Project</a>, which developed the first nuclear-fission, or atomic, bomb. After <a href="https://www.britannica.com/event/World-War-II" class="md-crosslink autoxref " data-show-preview="true">World War II</a>, the Los Alamos Scientific Laboratory (later called <span id="ref102064"></span><a href="https://www.britannica.com/topic/Los-Alamos-National-Laboratory" class="md-crosslink " data-show-preview="true">Los Alamos National Laboratory</a>) developed the first thermonuclear-fusion, or hydrogen, bomb. The laboratory, which is operated by the <a href="https://www.britannica.com/topic/University-of-California" class="md-crosslink autoxref " data-show-preview="true">University of California</a> under contract with the federal government, conducts solar and nuclear research and utilizes more than 300 buildings and a 77-square-mile (199-square-km) area.</p><div class="one-good-fact-module"> </div><span class="marker MOD2 mod-inline"></span><span class="marker PREMOD3 mod-inline"></span><p class="topic-paragraph">A modern city was built by the government to house employees of the laboratory. It was made “open” in 1957, and in 1962 there was a transfer of property from federal to private ownership. The laboratory remains the city’s largest employer. The city has a science museum and a history museum. <a href="https://www.britannica.com/place/Bandelier-National-Monument" class="md-crosslink " data-show-preview="true">Bandelier National Monument</a>, site of <a href="https://www.britannica.com/topic/Ancestral-Pueblo-culture" class="md-crosslink " data-show-preview="true">Ancestral Pueblo</a> (Anasazi) ruins, is nearby. Los Alamos was incorporated with a <a class="md-dictionary-link md-dictionary-tt-off eb" data-term="consolidated" href="https://www.britannica.com/dictionary/consolidated" data-type="EB">consolidated</a> city-county government in 1969. Pop. (2000) 11,909; (2010) 12,019.</p><div class="module-spacing"> </div><span class="marker MOD3 mod-inline"></span></section> <span class="md-signature">This article was most recently revised and updated by <a href="/editor/Amy-Tikkanen/6393">Amy Tikkanen</a>.</span><span class="marker end-of-content"></span><span class="marker after-article"></span></div> <div id="chatbot-root"></div> </div> </div> </div> <div class="ai-dialog-placeholder"></div> </div> </div> <aside class="col-md-da-320"></aside> </div> </div> </div> </div> </article></div> </div></div> </div> </main> <div id="md-footer"></div> <noscript><iframe src="//www.googletagmanager.com/ns.html?id=GTM-5W6NC8" height="0" width="0" style="display:none;visibility:hidden"></iframe></noscript> <script type="text/javascript" id="_informizely_script_tag"> var IzWidget = IzWidget || {}; (function (d) { var scriptElement = d.createElement('script'); scriptElement.type = 'text/javascript'; scriptElement.async = true; scriptElement.src = "https://insitez.blob.core.windows.net/site/f780f33e-a610-4ac2-af81-3eb184037547.js"; var node = d.getElementById('_informizely_script_tag'); node.parentNode.insertBefore(scriptElement, node); } )(document); </script>  <script> window.ap3c = window.ap3c || {}; var ap3c = window.ap3c; ap3c.cmd = ap3c.cmd || []; ap3c.cmd.push(function() { ap3c.init('ZO4siT4cLwnykPnzZWJtd3Byb2Q', 'https://engage.email.britannica.com/'); ap3c.track({v: 0}); }); ap3c.activity = function(act) { ap3c.act = (ap3c.act || []); ap3c.act.push(act); }; var s, t; s = document.createElement('script'); s.type = 'text/javascript'; s.src = "https://engage.email.britannica.com/app.js"; t = document.getElementsByTagName('script')[0]; t.parentNode.insertBefore(s, t); </script> <script class="marketing-page-info" type="application/json"> {"pageType":"Topic","templateName":"DESKTOP","pageNumber":1,"pagesTotal":1,"pageId":348272,"pageLength":230,"initialLoad":true,"lastPageOfScroll":false} </script> <script class="marketing-content-info" type="application/json"> [] </script> <script src="https://cdn.britannica.com/mendel-resources/3-130/js/libs/jquery-3.5.0.min.js?v=3.130.14"></script> <script type="text/javascript" data-type="Init Mendel Code Splitting"> (function() { $.ajax({ dataType: 'script', cache: true, url: 'https://cdn.britannica.com/mendel-resources/3-130/dist/topic-page.js?v=3.130.14' }); })(); </script> <script class="analytics-metadata" type="application/json"> {"leg":"A","adLeg":"A","userType":"ANONYMOUS","pageType":"Topic","pageSubtype":null,"articleTemplateType":"SMALL","gisted":false,"pageNumber":1,"hasSummarizeButton":false,"hasAskButton":false} </script> <script type="text/javascript"> EBStat={accountId:-1,hostnameOverride:'webstats.eb.com',domain:'www.britannica.com', json:''}; </script> <script type="text/javascript"> ( function() { $.ajax( { dataType: 'script', cache: true, url: '//www.britannica.com/webstats/mendelstats.js?v=1' } ) .done( function() { try {writeStat(null,EBStat);} catch(err){} } ); })(); </script> <div id="bc-fixed-dialogue"></div> </body> </html>

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