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#featured-post-5 h4 { font-size: 2.6rem; font-weight: 600; padding-top: 0; } /* -- */ #media_video-3 { background-color: #f5f5f5; padding: 0px 0px 0px 0px; } @media only screen and (max-width: 800px) { .one-half { margin: 0; width: 100%; } } .home h1.entry-title { display: none; margin-bottom: 0; } .home h2.entry-title { display: none; margin-bottom: 0; } .entry-header::after { display: block; margin: 0 auto 0px; padding-bottom: 0px; width: 10%; border-bottom: none; } #text-6 .textwidget { padding-bottom: 5rem; } .home-section-2 { background-color: #f5f5f5; } #text-13 .widget-wrap a { font-weight: 600; color: #00A0B2; } #text-13 .widget-wrap { font-size: 2.6rem; text-align: left; line-height: 150%; color: #999; } /* ---- HOME Highlights ---- */ #highlights { display: flex; flex-wrap: wrap; align-content: flex-start; justify-content: center; margin-top: -80px; padding-bottom: 0%; } #highlights a { flex-grow: 1; flex-basis: 255px; max-width: 300px; margin: 10px; } #highlights img { width: 100%; } #highlights h3 { font-size: 2.6rem; font-weight: 600; } .home-even .wrap, .home-odd .wrap { max-width: 980px; padding-left: 20px; padding-right: 20px; } p.more-from-category { display: none; } .one-half { padding: 3%; background: black; /* For browsers that do not support gradients */ background: linear-gradient(to bottom, rgba(0,0,0,.1), rgba(0,0,0,.8), rgba(0,0,0,.3)); /* Standard syntax (must be last) */ } .two-sixths { padding: 3%; background: black; /* For browsers that do not support gradients */ background: linear-gradient(to bottom, rgba(0,0,0,.1), rgba(0,0,0,.8), rgba(0,0,0,.3)); /* Standard syntax (must be last) */ } .one-sixth { padding: 3%; background: black; /* For browsers that do not support gradients */ background: linear-gradient(to bottom, rgba(0,0,0,.1), rgba(0,0,0,.8), rgba(0,0,0,.3)); /* Standard syntax (must be last) */ } .home-even.home-section-4.widget-area { background-color: #f8f8f8; margin-top: 0; padding-top: 40px; } .home h2 { font-size: 3.5rem; } .home-section-1 p { font-size: 2.0rem; } .home-section-2 h3.widgettitle.widget-title { display: none; } .home-section-2 h1 { font-size: 4.0rem; } .home-section-2.widget-area { margin-bottom: -60pt; } /* ---- HOME News ---- */ .home-section-4.widget-area { background-color: #f5f5f5; margin-top: 2%; margin-bottom: -100pt; } .home-section-4 h3.widgettitle.widget-title { font-size: 4.0rem; margin-bottom: 30pt; } .home-section-4 h4 { margin-top: -30pt; margin-bottom: -30pt; font-size: 2.0rem; } /* ---- HOME Sponsors ---- */ #custom_html-6 > div { display: flex; } ul.sponsor { display: flex; flex-wrap: wrap; list-style-type: none; align-items: center; justify-content: space-around; } li.sponsor-item { flex: 0 0 35%; margin: 20px; list-style-type: none; } li.sponsor-page-item { flex: 0 0 45%; margin: 12px; list-style-type: none; } .entry-content ul > li.sponsor-item { list-style-type: none; } .entry-content ul > li.sponsor-page-item { list-style-type: none; } @media only screen and (max-width: 800px) { ul.sponsor { flex-direction: column; flex-wrap: wrap; flex: 0 1 180px; align-items: center; max-width: 350px } .post-102 .entry-content p { text-align: center; } li.sponsor-item { margin: 30px; } } #custom_html-6 h3 { color: #999; padding-bottom: 20px; } #text-9 h3 { font-size: 3.3rem; color: #999; } /* CATEGORY -- ARCHIVE */ .category h2 { font-size: 18px; } .category article { margin-bottom: auto } .category div.site-inner { margin-bottom: 10%; } .category #genesis-sidebar-primary.sidebar.sidebar-primary.widget-area { margin-top: 160px; } .category-meet-a-desi-member h2 { font-size: 26px; font-weight: 700; padding-top: 20px; border-top: 2px solid #dedede; } .entry-header, .entry-title a { color: #00a0af; text-align: left; padding-bottom: 1%; font-weight: 600; font-size: 2.6rem;} .archive #genesis-sidebar-primary { background-color: #f8f8f8; padding: 0px; margin-top: 15%; } .archive #genesis-sidebar-primary h3.widget-title { font-size: 2rem; font-weight: 500; padding-bottom: 10px; } .archive #genesis-sidebar-primary h4.entry-title { font-size: 3rem; color: #00a0af; margin-bottom: 0; } .archive .sidebar .entry-title a { font-size: 2rem; color: #00a0af; margin-bottom: 0; } /* ARCHIVE PAGES */ .archive-description, .author-box { border-bottom: none; border-top: none; } .archive-title { font-size: 4.667rem; color: #333; font-weight: 500; line-height: 1; margin-bottom: 0; text-align: left; } .archive-description, .author-box { margin-bottom: 30px; } /* SIDEBAR */ .sidebar li { font-family: open-sans, sans-serif; font-size: 100%; line-height: 1.25; margin-bottom: 5%} .sidebar a:visited { color: #999; } ul#menu-blog, ul#menu-blog-spanish, ul#menu-collaboration, ul#menu-education-outreach, ul#menu-for-scientists, ul#menu-gallery, ul#menu-instrument, ul#menu-instrument-catalan, ul#menu-instrument-italian, ul#menu-instrument-spanish, ul#menu-meet-a-member, ul#menu-meet-a-member-spanish, ul#menu-press, ul#menu-science, ul#menu-science-catalan, ul#menu-science-chinese, ul#menu-science-english, ul#menu-science-french, ul#menu-science-georgian, ul#menu-science-german, ul#menu-science-italian, ul#menu-science-korean, ul#menu-science-portuguese, ul#menu-science-spanish { background-color: #f8f8f8; padding: 8%; } #nav_menu-17 { background-color: #f8f8f8; padding: 8%; } #nav_menu-17 h3 { margin-bottom: 0; } /* PAGES */ h1.entry-title { font-size: 4.8rem; margin-bottom: 6%; text-align: left; } div.photo-summary img { margin-bottom: 4%; } /* FULL-WIDTH */ .full-width .content { padding-right: 0px; font-size: 1.8rem; font-family: open-sans, sans-serif; } .full-width h1.entry-title { padding-left: 0px; } /* MISC */ .institute { font-weight: bold; color: #099; } hr { border-bottom: 1px solid #ddd; } /* EXTERNAL LINKS */ a.ext:after, .ext a:after, h3.ext:after { content: ''; display: inline-block; /* float: right; */ margin-left: 10px; width: 12px; height: 12px; background-image: url(/wp-content/uploads/sites/8/2018/06/ext-1.png); background-size: 24px 12px; background-repeat: no-repeat; background-position: -12px 0; } a.ext.white:after, .ext.white a:after, a.ext:hover:after, .ext a:hover:after { background-position:0 0; } .home-middle .ext:after, .entry-title-link.ext:after { content: ''; display: inline-block; width: 12px; height: 12px; background-image: url(images/ext.png); background-size:24px 12px; background-repeat:no-repeat; background-position:-12px 0; margin-left:8px; float:none; } /* ---- Flex Gallery ---- */ .children { display: flex; flex-flow: row wrap; justify-content: space-around; min-height: 200px; } .child { flex: 0 0 auto; list-style-type: none; width: 30%; padding: 25px; border: solid 1px #ddd; font-size: 1.6rem; } .child a { background-color: #fff; display: block; padding: 0; background-repeat: no-repeat; background-size: contain; background-position: center top; color: #333333; text-decoration: none; text-align: center; position: relative; } .child h3 { text-decoration: none; text-align: center; font-size: 2.3rem; font-weight: 600; /* letter-spacing: 3px; */ color: #fff; line-height: 0; margin-bottom: 0; } /* ---- FOOTER ---- */ .social-links img { height: 40px; padding-right: 20px; } a.footer-button { color: white; padding: 16px; text-align: center; text-decoration: none; display: inline-block; font-size: 16px; margin: 4px 30px 30px 0px; cursor: pointer; border-radius: 8px; border: 1px solid #fff; } .site-footer { display: none; } .footer-widgets a { text-decoration: none; display: inline; } footer .footer-social { margin: 36px 0 24px 0; padding: 0; font-size: 30px; text-align: center; } .copyright { font-size: 70%; padding-top: 20px; } .wp-caption-text { margin-top: 8px; }</style></head> <body class="page-template-default page page-id-16 custom-header header-image content-sidebar genesis-breadcrumbs-hidden genesis-footer-widgets-visible" itemscope itemtype="https://schema.org/WebPage"><div class="site-container"><ul class="genesis-skip-link"><li><a href="#genesis-content" class="screen-reader-shortcut"> Skip to main content</a></li><li><a href="#genesis-sidebar-primary" class="screen-reader-shortcut"> Skip to primary sidebar</a></li><li><a href="#genesis-footer-widgets" class="screen-reader-shortcut"> Skip to footer</a></li></ul><header class="site-header" itemscope itemtype="https://schema.org/WPHeader"><div class="wrap"><div class="title-area"><p class="site-title" itemprop="headline"><a href="https://www.desi.lbl.gov/">Dark Energy Spectroscopic Instrument (DESI)</a></p></div><div class="widget-area header-widget-area"><section id="nav_menu-20" class="widget widget_nav_menu"><div class="widget-wrap"><nav class="nav-header" itemscope itemtype="https://schema.org/SiteNavigationElement"><ul id="menu-main-navigation" class="menu genesis-nav-menu js-superfish"><li id="menu-item-59" class="menu-item menu-item-type-post_type menu-item-object-page current-menu-ancestor current-menu-parent current_page_parent current_page_ancestor menu-item-has-children menu-item-59"><a href="https://www.desi.lbl.gov/science/" itemprop="url"><span itemprop="name">/ science /</span></a> <ul class="sub-menu"> <li id="menu-item-994" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-994"><a href="https://www.desi.lbl.gov/science/" itemprop="url"><span itemprop="name">science overview</span></a></li> <li id="menu-item-77" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-77"><a href="https://www.desi.lbl.gov/cosmology-and-dark-energy/" itemprop="url"><span itemprop="name">cosmology and dark energy</span></a></li> <li id="menu-item-80" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-80"><a href="https://www.desi.lbl.gov/redshifts-and-distance/" itemprop="url"><span itemprop="name">redshifts and distance</span></a></li> <li id="menu-item-79" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-79"><a 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system</span></a></li> <li id="menu-item-93" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-93"><a href="https://www.desi.lbl.gov/data-systems/" itemprop="url"><span itemprop="name">data systems</span></a></li> <li id="menu-item-91" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-has-children menu-item-91"><a href="https://www.desi.lbl.gov/bringing-desi-to-life/" itemprop="url"><span itemprop="name">bringing DESI to life</span></a> <ul class="sub-menu"> <li id="menu-item-212" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-212"><a href="https://www.desi.lbl.gov/bringing-desi-to-life/commissioning-instrument/" itemprop="url"><span itemprop="name">commissioning Instrument</span></a></li> <li id="menu-item-213" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-213"><a href="https://www.desi.lbl.gov/bringing-desi-to-life/protodesi/" itemprop="url"><span itemprop="name">protoDESI</span></a></li> </ul> </li> </ul> </li> <li id="menu-item-61" class="collaboration menu-item menu-item-type-post_type menu-item-object-page menu-item-has-children menu-item-61"><a href="https://www.desi.lbl.gov/collaboration/" itemprop="url"><span itemprop="name">/ collaboration /</span></a> <ul class="sub-menu"> <li id="menu-item-169" class="ext menu-item menu-item-type-custom menu-item-object-custom menu-item-169"><a href="https://desi.lbl.gov/trac/wiki/PublicPages/Contacts" itemprop="url"><span itemprop="name">DESI team</span></a></li> <li id="menu-item-1020" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-1020"><a href="https://www.desi.lbl.gov/collaboration/desi-builders/" itemprop="url"><span itemprop="name">DESI builders</span></a></li> <li id="menu-item-113" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-113"><a href="https://www.desi.lbl.gov/collaborating-institutions/" itemprop="url"><span 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href="https://www.desi.lbl.gov/category/blog/" itemprop="url"><span itemprop="name">blog</span></a></li> <li id="menu-item-367" class="menu-item menu-item-type-custom menu-item-object-custom menu-item-367"><a href="https://twitter.com/desisurvey?ref_src=twsrc%5Etfw" itemprop="url"><span itemprop="name">tweets by desisurvey</span></a></li> <li id="menu-item-1159" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-1159"><a href="https://www.desi.lbl.gov/acknowledgements/" itemprop="url"><span itemprop="name">acknowledgments</span></a></li> </ul> </li> <li id="menu-item-366" class="menu-item menu-item-type-custom menu-item-object-custom menu-item-has-children menu-item-366"><a href="/photos/" itemprop="url"><span itemprop="name">/ galleries /</span></a> <ul class="sub-menu"> <li id="menu-item-133" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-133"><a href="https://www.desi.lbl.gov/photos/" itemprop="url"><span itemprop="name">image gallery</span></a></li> <li id="menu-item-132" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-132"><a href="https://www.desi.lbl.gov/videos/" itemprop="url"><span itemprop="name">videos</span></a></li> </ul> </li> <li id="menu-item-209" class="menu-item menu-item-type-custom menu-item-object-custom menu-item-has-children menu-item-209"><a href="/for-scientists/" itemprop="url"><span itemprop="name">/ for scientists /</span></a> <ul class="sub-menu"> <li id="menu-item-3401" class="menu-item menu-item-type-custom menu-item-object-custom menu-item-3401"><a href="https://data.desi.lbl.gov/doc" itemprop="url"><span itemprop="name">data releases</span></a></li> <li id="menu-item-208" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-208"><a href="https://www.desi.lbl.gov/for-scientists/instrument-design/" itemprop="url"><span itemprop="name">instrument design</span></a></li> <li id="menu-item-1512" class="menu-item menu-item-type-post_type 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menu-item-object-page menu-item-has-children menu-item-2141"><a href="https://www.desi.lbl.gov/education-outreach/" itemprop="url"><span itemprop="name">/ education & outreach /</span></a> <ul class="sub-menu"> <li id="menu-item-2661" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-2661"><a href="https://www.desi.lbl.gov/education-outreach/meet-a-desi-member-all/" itemprop="url"><span itemprop="name">meet a DESI member</span></a></li> <li id="menu-item-2665" class="menu-item menu-item-type-taxonomy menu-item-object-category menu-item-2665"><a href="https://www.desi.lbl.gov/category/blog/" itemprop="url"><span itemprop="name">blog</span></a></li> <li id="menu-item-3279" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-3279"><a href="https://www.desi.lbl.gov/education-outreach/planetarium-show/" itemprop="url"><span itemprop="name">planetarium show</span></a></li> <li id="menu-item-2142" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-2142"><a href="https://www.desi.lbl.gov/education-outreach/desi-high/" itemprop="url"><span itemprop="name">DESI high</span></a></li> <li id="menu-item-2666" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-2666"><a href="https://www.desi.lbl.gov/education-outreach/interactive-visualizations/" itemprop="url"><span itemprop="name">interactive visualizations</span></a></li> <li id="menu-item-2663" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-2663"><a href="https://www.desi.lbl.gov/education-outreach/desi-merch/" itemprop="url"><span itemprop="name">DESI Merch</span></a></li> </ul> </li> </ul></nav></div></section> </div></div></header><div class="site-inner"><div class="content-sidebar-wrap"><h1 class="entry-title" itemprop="headline">the DESI survey</h1> <main class="content" id="genesis-content"><article class="post-16 page type-page status-publish entry" aria-label="the DESI survey" itemscope itemtype="https://schema.org/CreativeWork"><div class="entry-content" itemprop="text"><p><a href="https://www.desi.lbl.gov/es/the-desi-survey-spanish"><img decoding="async" class="alignleft" src="https://www.desi.lbl.gov/wp-content/uploads/sites/8/2019/12/spanish-1-e1576602273893.png" width="50" height="50" /></a><a href="https://www.desi.lbl.gov/fr/the-desi-survey-french"><img decoding="async" class="alignleft" src="https://www.desi.lbl.gov/wp-content/uploads/sites/8/2020/03/france-512-e1585601646579.png" alt="" width="50" height="50" /></a><a href="//www.desi.lbl.gov/kr/the-desi-survey-korean"><img loading="lazy" decoding="async" class="alignleft" src="https://www.desi.lbl.gov/wp-content/uploads/sites/8/2020/09/Korean_flag.png" width="70" height="50" /></a><a href="https://www.desi.lbl.gov/zh/the-desi-survey-chinese"><img loading="lazy" decoding="async" class="alignleft" src="https://www.desi.lbl.gov/wp-content/uploads/sites/8/2021/01/chinese-1-e1612247124782.png" alt="" width="50" height="50" /></a><a href="https://www.desi.lbl.gov/ka/the-desi-survey-georgian"><img loading="lazy" decoding="async" class="alignleft" src="https://www.desi.lbl.gov/wp-content/uploads/sites/8/2021/02/geo-flag-e1613113476346.png" width="50" height="50" /></a><a href="https://www.desi.lbl.gov/pt/the-desi-survey-portuguese"><img loading="lazy" decoding="async" class="alignleft" src="https://www.desi.lbl.gov/wp-content/uploads/sites/8/2021/03/pt-br-e1615507733955.png" width="50" height="50" /></a><a href="https://www.desi.lbl.gov/de/the-desi-survey-german"><img loading="lazy" decoding="async" class="alignleft" src="https://www.desi.lbl.gov/wp-content/uploads/sites/8/2021/07/de-flag-e1627535531831.png" width="50" height="50" /></a><a href="https://www.desi.lbl.gov/ca/the-desi-survey-catalan"><img loading="lazy" decoding="async" class="alignleft" src="https://www.desi.lbl.gov/wp-content/uploads/sites/8/2021/08/3253480-catalonia-icon-flag_106770-e1629935057530.png" width="50" height="50" /></a><a href="https://www.desi.lbl.gov/it/the-desi-survey-italian"><img loading="lazy" decoding="async" class="alignleft" src="https://www.desi.lbl.gov/wp-content/uploads/sites/8/2021/12/flag_italy-600x600.png" width="50" height="50" /></a></p> <p><a href="/wp-content/uploads/sites/8/2018/06/1.png"><img loading="lazy" decoding="async" class="wp-image-296 size-full alignnone" src="/wp-content/uploads/sites/8/2018/06/1.png" alt="" width="701" height="426" srcset="https://www.desi.lbl.gov/wp-content/uploads/sites/8/2018/06/1.png 701w, https://www.desi.lbl.gov/wp-content/uploads/sites/8/2018/06/1-600x365.png 600w, https://www.desi.lbl.gov/wp-content/uploads/sites/8/2018/06/1-300x182.png 300w" sizes="auto, (max-width: 701px) 100vw, 701px" /></a></p> <p class="lead">DESI seeks to map the large-scale structure of the universe over an enormous volume and a wide range of look-back times (based on “redshift,” or the shift in the light of distant objects toward redder wavelengths of light). Targeting about 30 million pre-selected galaxies across one-third of the night sky, scientists will use DESI’s redshifts data to construct 3D maps of the universe.</p> <p>The DESI survey is based on four primary classes of galaxies, here described in order of distance from us:</p> <ol> <li>DESI will provide a detailed map using <strong>bright galaxies</strong>, stretching out to redshift 0.4 and including galaxies to 20th magnitude. These objects are bright enough to observe when the moon is near full. While these are the easiest targets, they are still of high value because they probe the universe most recently, when the accelerating expansion is strongest.</li> <li>Next, DESI will use <strong>luminous red galaxies</strong> (LRGs). These are the most massive galaxies, composed largely of old stars. They can be seen at substantial distances and their red color makes them easy to select in imaging. With them, the survey will reach redshift 1.</li> <li>The largest sample in DESI relies on <strong>emission line galaxies</strong> (ELGs). These are fainter and more distant, but their vigorous star formation and hot young stars create strong emission in distinct wavelengths that DESI can detect out to redshift 1.6.</li> <li>To go yet further, DESI will survey <strong>quasars</strong>. These are galaxies where the central supermassive black hole is accreting large amounts of gas that is glowing as it reaches relativistic speeds. Quasars outshine the stars of the galaxy and achieve luminosities that allow DESI to detect them out to redshift 3.5 and beyond.</li> </ol> <p>An important extra application of the quasars is that their spectra is altered by the light traveling through the intergalactic gas between the quasar and us. The neutral hydrogen in this gas produces absorption at a key wavelength in the ultraviolet (121.6 nanometers), and that absorption pattern gets shifted into visible wavelengths due to the very high redshift of the gas. This produces a so-called <strong>Lyman-alpha forest</strong> and means that each quasar spectrum not only reveals its location in the map, but also a map of the intergalactic hydrogen along the line of sight.</p> <p>Finally, DESI will observe <strong>stars in our own galaxy</strong>, adding to our understanding of the chemical abundances and gravitational dynamics of the Milky Way, particularly to help our study of the role of dark matter.</p> <p style="text-align: right"><strong><a href="https://www.desi.lbl.gov/imaging-surveys">imaging surveys 禄</a></strong></p> </div></article></main><aside class="sidebar sidebar-primary widget-area" role="complementary" aria-label="Primary Sidebar" itemscope itemtype="https://schema.org/WPSideBar" id="genesis-sidebar-primary"><h2 class="genesis-sidebar-title screen-reader-text">Primary Sidebar</h2><section id="nav_menu-49" class="widget widget_nav_menu"><div class="widget-wrap"><div class="menu-science-english-container"><ul id="menu-science-english" class="menu"><li id="menu-item-406" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-406"><a href="https://www.desi.lbl.gov/science/" itemprop="url">science overview</a></li> <li id="menu-item-228" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-228"><a href="https://www.desi.lbl.gov/cosmology-and-dark-energy/" itemprop="url">cosmology and dark energy</a></li> <li id="menu-item-230" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-230"><a href="https://www.desi.lbl.gov/redshifts-and-distance/" itemprop="url">redshifts and distance</a></li> <li id="menu-item-229" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-229"><a href="https://www.desi.lbl.gov/mapping-the-universe/" itemprop="url">mapping the universe</a></li> <li id="menu-item-231" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-231"><a href="https://www.desi.lbl.gov/the-desi-science-mission/" itemprop="url">the DESI science mission</a></li> <li id="menu-item-232" class="menu-item menu-item-type-post_type menu-item-object-page current-menu-item page_item page-item-16 current_page_item menu-item-232"><a href="https://www.desi.lbl.gov/the-desi-survey/" aria-current="page" itemprop="url">the DESI survey</a></li> <li id="menu-item-233" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-233"><a href="https://www.desi.lbl.gov/imaging-surveys/" itemprop="url">imaging surveys</a></li> </ul></div></div></section> </aside></div></div><div class="footer-widgets" id="genesis-footer-widgets"><h2 class="genesis-sidebar-title screen-reader-text">Footer</h2><div class="wrap"><div class="widget-area footer-widgets-1 footer-widget-area"><section id="custom_html-4" class="widget_text widget widget_custom_html"><div class="widget_text widget-wrap"><div class="textwidget custom-html-widget"><div> <p> <a href="https://desi.lbl.gov/trac/login" class="footer-button">TEAM LOGIN</a></p> <p class="social-links"> <a class="twitter" href="https://twitter.com/desisurvey" target="_blank"><img src="/wp-content/uploads/sites/8/2018/06/twitter-icon@05x.png" alt="twitter"></a>   <a class="item2 ir" href="https://www.instagram.com/desisurvey/?hl=en" target="_blank"><img src="/wp-content/uploads/sites/8/2018/06/instagram-icon@05x.png" alt="instagram"></a>   <a class="item3 ir" href="https://www.facebook.com/DESI-Survey-2104105159914082/?modal=admin_todo_tour" target="_blank"><img src="/wp-content/uploads/sites/8/2018/06/facebook-icon@05x.png" alt="facebook"></a> </p> </div> <p class="copyright"> Copyright 漏 2018 Dark Energy Spectroscopic Instrument [DESI] </p></div></div></section> </div></div></div><footer class="site-footer" itemscope itemtype="https://schema.org/WPFooter"><div class="wrap"><p>Copyright © 2025 路 <a href="http://my.studiopress.com/themes/parallax/">Parallax Pro DESI</a> on <a href="https://www.studiopress.com/">Genesis Framework</a> 路 <a href="https://wordpress.org/">WordPress</a> 路 <a href="https://www.desi.lbl.gov/wp-login.php">Log in</a></p></div></footer></div><script type="text/javascript" src="https://www.desi.lbl.gov/wp-includes/js/hoverIntent.min.js?ver=1.10.2" id="hoverIntent-js"></script> <script type="text/javascript" src="https://www.desi.lbl.gov/wp-content/themes/genesis/lib/js/menu/superfish.min.js?ver=1.7.10" id="superfish-js"></script> <script type="text/javascript" src="https://www.desi.lbl.gov/wp-content/themes/genesis/lib/js/menu/superfish.args.min.js?ver=3.4.0" id="superfish-args-js"></script> <script type="text/javascript" src="https://www.desi.lbl.gov/wp-content/themes/genesis/lib/js/skip-links.min.js?ver=3.4.0" id="skip-links-js"></script> <script type="text/javascript" id="parallax-responsive-menu-js-extra"> /* <![CDATA[ */ var genesis_responsive_menu = {"mainMenu":"Menu","subMenu":"Submenu","menuClasses":{"combine":[".nav-header",".nav-primary"]}}; 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