CINXE.COM

<!DOCTYPE html> <html dir="ltr" lang="en-US" prefix="og: https://ogp.me/ns#"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <link rel="profile" href="https://gmpg.org/xfn/11"> <title>Serving up the Universe on a plate - SDSS</title>  <meta name="description" content="They may not look like much — just metal disks 80 centimeters (30 inches) across with some etched markings and hundreds of small holes — but round aluminum “plates” like this one from the Sloan Digital Sky Survey (SDSS) have been vital to mapping our universe for more than 20 years. “The light passing through" /> <meta name="robots" content="max-image-preview:large" /> <link rel="canonical" href="https://www.sdss.org/serving-up-the-universe-on-a-plate/" /> <meta name="generator" content="All in One SEO (AIOSEO) 4.6.7.1" /> <meta property="og:locale" content="en_US" /> <meta property="og:site_name" content="SDSS - Mapping the Universe" /> <meta property="og:type" content="article" /> <meta property="og:title" content="Serving up the Universe on a plate - SDSS" /> <meta property="og:description" content="They may not look like much — just metal disks 80 centimeters (30 inches) across with some etched markings and hundreds of small holes — but round aluminum “plates” like this one from the Sloan Digital Sky Survey (SDSS) have been vital to mapping our universe for more than 20 years. “The light passing through" /> <meta property="og:url" content="https://www.sdss.org/serving-up-the-universe-on-a-plate/" /> <meta property="og:image" content="https://www.sdss.org/wp-content/uploads/2022/09/sdss-new-logo-72dpi.png" /> <meta property="og:image:secure_url" content="https://www.sdss.org/wp-content/uploads/2022/09/sdss-new-logo-72dpi.png" /> <meta property="article:published_time" content="2021-07-13T18:26:00+00:00" /> <meta property="article:modified_time" content="2024-08-23T15:16:53+00:00" /> <meta name="twitter:card" content="summary_large_image" /> <meta name="twitter:title" content="Serving up the Universe on a plate - SDSS" /> <meta name="twitter:description" content="They may not look like much — just metal disks 80 centimeters (30 inches) across with some etched markings and hundreds of small holes — but round aluminum “plates” like this one from the Sloan Digital Sky Survey (SDSS) have been vital to mapping our universe for more than 20 years. “The light passing through" /> <meta name="twitter:image" content="https://www.sdss.org/wp-content/uploads/2022/09/sdss-new-logo-72dpi.png" /> <script type="application/ld+json" class="aioseo-schema"> {"@context":"https:\/\/schema.org","@graph":[{"@type":"BlogPosting","@id":"https:\/\/www.sdss.org\/serving-up-the-universe-on-a-plate\/#blogposting","name":"Serving up the Universe on a plate - SDSS","headline":"Serving up the Universe on a plate","author":{"@id":"https:\/\/www.sdss.org\/author\/raddick\/#author"},"publisher":{"@id":"https:\/\/www.sdss.org\/#organization"},"image":{"@type":"ImageObject","url":"\/wp-content\/uploads\/2022\/04\/schlegel.jpeg","@id":"https:\/\/www.sdss.org\/serving-up-the-universe-on-a-plate\/#articleImage"},"datePublished":"2021-07-13T18:26:00+00:00","dateModified":"2024-08-23T15:16:53+00:00","inLanguage":"en-US","mainEntityOfPage":{"@id":"https:\/\/www.sdss.org\/serving-up-the-universe-on-a-plate\/#webpage"},"isPartOf":{"@id":"https:\/\/www.sdss.org\/serving-up-the-universe-on-a-plate\/#webpage"},"articleSection":"News Releases"},{"@type":"BreadcrumbList","@id":"https:\/\/www.sdss.org\/serving-up-the-universe-on-a-plate\/#breadcrumblist","itemListElement":[{"@type":"ListItem","@id":"https:\/\/www.sdss.org\/#listItem","position":1,"name":"Home","item":"https:\/\/www.sdss.org\/","nextItem":"https:\/\/www.sdss.org\/serving-up-the-universe-on-a-plate\/#listItem"},{"@type":"ListItem","@id":"https:\/\/www.sdss.org\/serving-up-the-universe-on-a-plate\/#listItem","position":2,"name":"Serving up the Universe on a plate","previousItem":"https:\/\/www.sdss.org\/#listItem"}]},{"@type":"Organization","@id":"https:\/\/www.sdss.org\/#organization","name":"SDSS","description":"Mapping the Universe","url":"https:\/\/www.sdss.org\/","logo":{"@type":"ImageObject","url":"\/wp-content\/uploads\/2022\/09\/sdss-new-logo-72dpi.png","@id":"https:\/\/www.sdss.org\/serving-up-the-universe-on-a-plate\/#organizationLogo"},"image":{"@id":"https:\/\/www.sdss.org\/serving-up-the-universe-on-a-plate\/#organizationLogo"},"sameAs":["https:\/\/en.wikipedia.org\/wiki\/Sloan_Digital_Sky_Survey"]},{"@type":"Person","@id":"https:\/\/www.sdss.org\/author\/raddick\/#author","url":"https:\/\/www.sdss.org\/author\/raddick\/","name":"raddick","image":{"@type":"ImageObject","@id":"https:\/\/www.sdss.org\/serving-up-the-universe-on-a-plate\/#authorImage","url":"https:\/\/secure.gravatar.com\/avatar\/c357df74c988d4d595d59cb8021f1060?s=96&d=mm&r=g","width":96,"height":96,"caption":"raddick"}},{"@type":"WebPage","@id":"https:\/\/www.sdss.org\/serving-up-the-universe-on-a-plate\/#webpage","url":"https:\/\/www.sdss.org\/serving-up-the-universe-on-a-plate\/","name":"Serving up the Universe on a plate - SDSS","description":"They may not look like much \u2014 just metal disks 80 centimeters (30 inches) across with some etched markings and hundreds of small holes \u2014 but round aluminum \u201cplates\u201d like this one from the Sloan Digital Sky Survey (SDSS) have been vital to mapping our universe for more than 20 years. \u201cThe light passing through","inLanguage":"en-US","isPartOf":{"@id":"https:\/\/www.sdss.org\/#website"},"breadcrumb":{"@id":"https:\/\/www.sdss.org\/serving-up-the-universe-on-a-plate\/#breadcrumblist"},"author":{"@id":"https:\/\/www.sdss.org\/author\/raddick\/#author"},"creator":{"@id":"https:\/\/www.sdss.org\/author\/raddick\/#author"},"datePublished":"2021-07-13T18:26:00+00:00","dateModified":"2024-08-23T15:16:53+00:00"},{"@type":"WebSite","@id":"https:\/\/www.sdss.org\/#website","url":"https:\/\/www.sdss.org\/","name":"SDSS","description":"Mapping the Universe","inLanguage":"en-US","publisher":{"@id":"https:\/\/www.sdss.org\/#organization"}}]} </script>  <link rel='dns-prefetch' href='//www.sdss.org' /> <link rel="alternate" type="application/rss+xml" title="SDSS » Feed" href="https://www.sdss.org/feed/" /> <link rel="alternate" type="application/rss+xml" title="SDSS » Comments Feed" href="https://www.sdss.org/comments/feed/" />  <script src="//www.googletagmanager.com/gtag/js?id=G-5BJ0FDW1X0" data-cfasync="false" data-wpfc-render="false" async></script> <script data-cfasync="false" data-wpfc-render="false"> var mi_version = '8.28.0'; var mi_track_user = true; var mi_no_track_reason = ''; var MonsterInsightsDefaultLocations = {"page_location":"https:\/\/www.sdss.org\/serving-up-the-universe-on-a-plate\/"}; if ( typeof MonsterInsightsPrivacyGuardFilter === 'function' ) { var MonsterInsightsLocations = (typeof MonsterInsightsExcludeQuery === 'object') ? MonsterInsightsPrivacyGuardFilter( MonsterInsightsExcludeQuery ) : MonsterInsightsPrivacyGuardFilter( MonsterInsightsDefaultLocations ); } else { var MonsterInsightsLocations = (typeof MonsterInsightsExcludeQuery === 'object') ? MonsterInsightsExcludeQuery : MonsterInsightsDefaultLocations; } var disableStrs = [ 'ga-disable-G-5BJ0FDW1X0', ]; /* Function to detect opted out users */ function __gtagTrackerIsOptedOut() { for (var index = 0; index < disableStrs.length; index++) { if (document.cookie.indexOf(disableStrs[index] + '=true') > -1) { return true; } } return false; } /* Disable tracking if the opt-out cookie exists. */ if (__gtagTrackerIsOptedOut()) { for (var index = 0; index < disableStrs.length; index++) { window[disableStrs[index]] = true; } } /* Opt-out function */ function __gtagTrackerOptout() { for (var index = 0; index < disableStrs.length; index++) { document.cookie = disableStrs[index] + '=true; expires=Thu, 31 Dec 2099 23:59:59 UTC; path=/'; window[disableStrs[index]] = true; } } if ('undefined' === typeof gaOptout) { function gaOptout() { __gtagTrackerOptout(); } } window.dataLayer = window.dataLayer || []; window.MonsterInsightsDualTracker = { helpers: {}, trackers: {}, }; if (mi_track_user) { function __gtagDataLayer() { dataLayer.push(arguments); } function __gtagTracker(type, name, parameters) { if (!parameters) { parameters = {}; } if (parameters.send_to) { __gtagDataLayer.apply(null, arguments); return; } if (type === 'event') { parameters.send_to = monsterinsights_frontend.v4_id; var hookName = name; if (typeof parameters['event_category'] !== 'undefined') { hookName = parameters['event_category'] + ':' + name; } if (typeof MonsterInsightsDualTracker.trackers[hookName] !== 'undefined') { MonsterInsightsDualTracker.trackers[hookName](parameters); } else { __gtagDataLayer('event', name, parameters); } } else { __gtagDataLayer.apply(null, arguments); } } __gtagTracker('js', new Date()); __gtagTracker('set', { 'developer_id.dZGIzZG': true, }); if ( MonsterInsightsLocations.page_location ) { __gtagTracker('set', MonsterInsightsLocations); } __gtagTracker('config', 'G-5BJ0FDW1X0', {"forceSSL":"true","link_attribution":"true"} ); window.gtag = __gtagTracker; (function () { /* https://developers.google.com/analytics/devguides/collection/analyticsjs/ */ /* ga and __gaTracker compatibility shim. */ var noopfn = function () { return null; }; var newtracker = function () { return new Tracker(); }; var Tracker = function () { return null; }; var p = Tracker.prototype; p.get = noopfn; p.set = noopfn; p.send = function () { var args = Array.prototype.slice.call(arguments); args.unshift('send'); __gaTracker.apply(null, args); }; var __gaTracker = function () { var len = arguments.length; if (len === 0) { return; } var f = arguments[len - 1]; if (typeof f !== 'object' || f === null || typeof f.hitCallback !== 'function') { if ('send' === arguments[0]) { var hitConverted, hitObject = false, action; if ('event' === arguments[1]) { if ('undefined' !== typeof arguments[3]) { hitObject = { 'eventAction': arguments[3], 'eventCategory': arguments[2], 'eventLabel': arguments[4], 'value': arguments[5] ? arguments[5] : 1, } } } if ('pageview' === arguments[1]) { if ('undefined' !== typeof arguments[2]) { hitObject = { 'eventAction': 'page_view', 'page_path': arguments[2], } } } if (typeof arguments[2] === 'object') { hitObject = arguments[2]; } if (typeof arguments[5] === 'object') { Object.assign(hitObject, arguments[5]); } if ('undefined' !== typeof arguments[1].hitType) { hitObject = arguments[1]; if ('pageview' === hitObject.hitType) { hitObject.eventAction = 'page_view'; } } if (hitObject) { action = 'timing' === arguments[1].hitType ? 'timing_complete' : hitObject.eventAction; hitConverted = mapArgs(hitObject); __gtagTracker('event', action, hitConverted); } } return; } function mapArgs(args) { var arg, hit = {}; var gaMap = { 'eventCategory': 'event_category', 'eventAction': 'event_action', 'eventLabel': 'event_label', 'eventValue': 'event_value', 'nonInteraction': 'non_interaction', 'timingCategory': 'event_category', 'timingVar': 'name', 'timingValue': 'value', 'timingLabel': 'event_label', 'page': 'page_path', 'location': 'page_location', 'title': 'page_title', 'referrer' : 'page_referrer', }; for (arg in args) { if (!(!args.hasOwnProperty(arg) || !gaMap.hasOwnProperty(arg))) { hit[gaMap[arg]] = args[arg]; } else { hit[arg] = args[arg]; } } return hit; } try { f.hitCallback(); } catch (ex) { } }; __gaTracker.create = newtracker; __gaTracker.getByName = newtracker; __gaTracker.getAll = function () { return []; }; __gaTracker.remove = noopfn; __gaTracker.loaded = true; window['__gaTracker'] = __gaTracker; })(); } else { console.log(""); (function () { function __gtagTracker() { return null; } window['__gtagTracker'] = __gtagTracker; window['gtag'] = __gtagTracker; })(); } </script>  <script> window._wpemojiSettings = {"baseUrl":"https:\/\/s.w.org\/images\/core\/emoji\/15.0.3\/72x72\/","ext":".png","svgUrl":"https:\/\/s.w.org\/images\/core\/emoji\/15.0.3\/svg\/","svgExt":".svg","source":{"concatemoji":"https:\/\/www.sdss.org\/wp-includes\/js\/wp-emoji-release.min.js?ver=6.6"}}; /*! This file is auto-generated */ !function(i,n){var o,s,e;function c(e){try{var t={supportTests:e,timestamp:(new Date).valueOf()};sessionStorage.setItem(o,JSON.stringify(t))}catch(e){}}function p(e,t,n){e.clearRect(0,0,e.canvas.width,e.canvas.height),e.fillText(t,0,0);var t=new Uint32Array(e.getImageData(0,0,e.canvas.width,e.canvas.height).data),r=(e.clearRect(0,0,e.canvas.width,e.canvas.height),e.fillText(n,0,0),new Uint32Array(e.getImageData(0,0,e.canvas.width,e.canvas.height).data));return t.every(function(e,t){return e===r[t]})}function u(e,t,n){switch(t){case"flag":return n(e,"\ud83c\udff3\ufe0f\u200d\u26a7\ufe0f","\ud83c\udff3\ufe0f\u200b\u26a7\ufe0f")?!1:!n(e,"\ud83c\uddfa\ud83c\uddf3","\ud83c\uddfa\u200b\ud83c\uddf3")&&!n(e,"\ud83c\udff4\udb40\udc67\udb40\udc62\udb40\udc65\udb40\udc6e\udb40\udc67\udb40\udc7f","\ud83c\udff4\u200b\udb40\udc67\u200b\udb40\udc62\u200b\udb40\udc65\u200b\udb40\udc6e\u200b\udb40\udc67\u200b\udb40\udc7f");case"emoji":return!n(e,"\ud83d\udc26\u200d\u2b1b","\ud83d\udc26\u200b\u2b1b")}return!1}function f(e,t,n){var r="undefined"!=typeof WorkerGlobalScope&&self instanceof WorkerGlobalScope?new OffscreenCanvas(300,150):i.createElement("canvas"),a=r.getContext("2d",{willReadFrequently:!0}),o=(a.textBaseline="top",a.font="600 32px Arial",{});return e.forEach(function(e){o[e]=t(a,e,n)}),o}function t(e){var t=i.createElement("script");t.src=e,t.defer=!0,i.head.appendChild(t)}"undefined"!=typeof Promise&&(o="wpEmojiSettingsSupports",s=["flag","emoji"],n.supports={everything:!0,everythingExceptFlag:!0},e=new Promise(function(e){i.addEventListener("DOMContentLoaded",e,{once:!0})}),new Promise(function(t){var n=function(){try{var e=JSON.parse(sessionStorage.getItem(o));if("object"==typeof e&&"number"==typeof e.timestamp&&(new Date).valueOf()<e.timestamp+604800&&"object"==typeof e.supportTests)return e.supportTests}catch(e){}return null}();if(!n){if("undefined"!=typeof Worker&&"undefined"!=typeof OffscreenCanvas&&"undefined"!=typeof URL&&URL.createObjectURL&&"undefined"!=typeof Blob)try{var e="postMessage("+f.toString()+"("+[JSON.stringify(s),u.toString(),p.toString()].join(",")+"));",r=new Blob([e],{type:"text/javascript"}),a=new Worker(URL.createObjectURL(r),{name:"wpTestEmojiSupports"});return void(a.onmessage=function(e){c(n=e.data),a.terminate(),t(n)})}catch(e){}c(n=f(s,u,p))}t(n)}).then(function(e){for(var t in e)n.supports[t]=e[t],n.supports.everything=n.supports.everything&&n.supports[t],"flag"!==t&&(n.supports.everythingExceptFlag=n.supports.everythingExceptFlag&&n.supports[t]);n.supports.everythingExceptFlag=n.supports.everythingExceptFlag&&!n.supports.flag,n.DOMReady=!1,n.readyCallback=function(){n.DOMReady=!0}}).then(function(){return e}).then(function(){var e;n.supports.everything||(n.readyCallback(),(e=n.source||{}).concatemoji?t(e.concatemoji):e.wpemoji&&e.twemoji&&(t(e.twemoji),t(e.wpemoji)))}))}((window,document),window._wpemojiSettings); </script> <link rel='stylesheet' id='wp-quicklatex-format-css' href='https://www.sdss.org/wp-content/plugins/wp-quicklatex/css/quicklatex-format.css?ver=6.6' media='all' /> <style id='wp-emoji-styles-inline-css'> img.wp-smiley, img.emoji { display: inline !important; border: none !important; box-shadow: none !important; height: 1em !important; width: 1em !important; margin: 0 0.07em !important; vertical-align: -0.1em !important; background: none !important; padding: 0 !important; } </style> <link rel='stylesheet' id='wp-block-library-css' href='https://www.sdss.org/wp-includes/css/dist/block-library/style.min.css?ver=6.6' media='all' /> <style id='pdfemb-pdf-embedder-viewer-style-inline-css'> .wp-block-pdfemb-pdf-embedder-viewer{max-width:none} </style> <style id='classic-theme-styles-inline-css'> /*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} </style> <style id='global-styles-inline-css'> :root{--wp--preset--aspect-ratio--square: 1;--wp--preset--aspect-ratio--4-3: 4/3;--wp--preset--aspect-ratio--3-4: 3/4;--wp--preset--aspect-ratio--3-2: 3/2;--wp--preset--aspect-ratio--2-3: 2/3;--wp--preset--aspect-ratio--16-9: 16/9;--wp--preset--aspect-ratio--9-16: 9/16;--wp--preset--color--black: #000000;--wp--preset--color--cyan-bluish-gray: #abb8c3;--wp--preset--color--white: #ffffff;--wp--preset--color--pale-pink: #f78da7;--wp--preset--color--vivid-red: #cf2e2e;--wp--preset--color--luminous-vivid-orange: #ff6900;--wp--preset--color--luminous-vivid-amber: #fcb900;--wp--preset--color--light-green-cyan: #7bdcb5;--wp--preset--color--vivid-green-cyan: #00d084;--wp--preset--color--pale-cyan-blue: #8ed1fc;--wp--preset--color--vivid-cyan-blue: #0693e3;--wp--preset--color--vivid-purple: #9b51e0;--wp--preset--gradient--vivid-cyan-blue-to-vivid-purple: linear-gradient(135deg,rgba(6,147,227,1) 0%,rgb(155,81,224) 100%);--wp--preset--gradient--light-green-cyan-to-vivid-green-cyan: linear-gradient(135deg,rgb(122,220,180) 0%,rgb(0,208,130) 100%);--wp--preset--gradient--luminous-vivid-amber-to-luminous-vivid-orange: linear-gradient(135deg,rgba(252,185,0,1) 0%,rgba(255,105,0,1) 100%);--wp--preset--gradient--luminous-vivid-orange-to-vivid-red: linear-gradient(135deg,rgba(255,105,0,1) 0%,rgb(207,46,46) 100%);--wp--preset--gradient--very-light-gray-to-cyan-bluish-gray: linear-gradient(135deg,rgb(238,238,238) 0%,rgb(169,184,195) 100%);--wp--preset--gradient--cool-to-warm-spectrum: linear-gradient(135deg,rgb(74,234,220) 0%,rgb(151,120,209) 20%,rgb(207,42,186) 40%,rgb(238,44,130) 60%,rgb(251,105,98) 80%,rgb(254,248,76) 100%);--wp--preset--gradient--blush-light-purple: linear-gradient(135deg,rgb(255,206,236) 0%,rgb(152,150,240) 100%);--wp--preset--gradient--blush-bordeaux: linear-gradient(135deg,rgb(254,205,165) 0%,rgb(254,45,45) 50%,rgb(107,0,62) 100%);--wp--preset--gradient--luminous-dusk: linear-gradient(135deg,rgb(255,203,112) 0%,rgb(199,81,192) 50%,rgb(65,88,208) 100%);--wp--preset--gradient--pale-ocean: linear-gradient(135deg,rgb(255,245,203) 0%,rgb(182,227,212) 50%,rgb(51,167,181) 100%);--wp--preset--gradient--electric-grass: linear-gradient(135deg,rgb(202,248,128) 0%,rgb(113,206,126) 100%);--wp--preset--gradient--midnight: linear-gradient(135deg,rgb(2,3,129) 0%,rgb(40,116,252) 100%);--wp--preset--font-size--small: 13px;--wp--preset--font-size--medium: 20px;--wp--preset--font-size--large: 36px;--wp--preset--font-size--x-large: 42px;--wp--preset--spacing--20: 0.44rem;--wp--preset--spacing--30: 0.67rem;--wp--preset--spacing--40: 1rem;--wp--preset--spacing--50: 1.5rem;--wp--preset--spacing--60: 2.25rem;--wp--preset--spacing--70: 3.38rem;--wp--preset--spacing--80: 5.06rem;--wp--preset--shadow--natural: 6px 6px 9px rgba(0, 0, 0, 0.2);--wp--preset--shadow--deep: 12px 12px 50px rgba(0, 0, 0, 0.4);--wp--preset--shadow--sharp: 6px 6px 0px rgba(0, 0, 0, 0.2);--wp--preset--shadow--outlined: 6px 6px 0px -3px rgba(255, 255, 255, 1), 6px 6px rgba(0, 0, 0, 1);--wp--preset--shadow--crisp: 6px 6px 0px rgba(0, 0, 0, 1);}:where(.is-layout-flex){gap: 0.5em;}:where(.is-layout-grid){gap: 0.5em;}body .is-layout-flex{display: flex;}.is-layout-flex{flex-wrap: wrap;align-items: center;}.is-layout-flex > :is(*, div){margin: 0;}body .is-layout-grid{display: grid;}.is-layout-grid > :is(*, div){margin: 0;}:where(.wp-block-columns.is-layout-flex){gap: 2em;}:where(.wp-block-columns.is-layout-grid){gap: 2em;}:where(.wp-block-post-template.is-layout-flex){gap: 1.25em;}:where(.wp-block-post-template.is-layout-grid){gap: 1.25em;}.has-black-color{color: var(--wp--preset--color--black) !important;}.has-cyan-bluish-gray-color{color: var(--wp--preset--color--cyan-bluish-gray) !important;}.has-white-color{color: var(--wp--preset--color--white) !important;}.has-pale-pink-color{color: var(--wp--preset--color--pale-pink) !important;}.has-vivid-red-color{color: var(--wp--preset--color--vivid-red) !important;}.has-luminous-vivid-orange-color{color: var(--wp--preset--color--luminous-vivid-orange) !important;}.has-luminous-vivid-amber-color{color: var(--wp--preset--color--luminous-vivid-amber) !important;}.has-light-green-cyan-color{color: var(--wp--preset--color--light-green-cyan) !important;}.has-vivid-green-cyan-color{color: var(--wp--preset--color--vivid-green-cyan) !important;}.has-pale-cyan-blue-color{color: var(--wp--preset--color--pale-cyan-blue) !important;}.has-vivid-cyan-blue-color{color: var(--wp--preset--color--vivid-cyan-blue) !important;}.has-vivid-purple-color{color: var(--wp--preset--color--vivid-purple) !important;}.has-black-background-color{background-color: var(--wp--preset--color--black) !important;}.has-cyan-bluish-gray-background-color{background-color: var(--wp--preset--color--cyan-bluish-gray) !important;}.has-white-background-color{background-color: var(--wp--preset--color--white) !important;}.has-pale-pink-background-color{background-color: var(--wp--preset--color--pale-pink) !important;}.has-vivid-red-background-color{background-color: var(--wp--preset--color--vivid-red) !important;}.has-luminous-vivid-orange-background-color{background-color: var(--wp--preset--color--luminous-vivid-orange) !important;}.has-luminous-vivid-amber-background-color{background-color: var(--wp--preset--color--luminous-vivid-amber) !important;}.has-light-green-cyan-background-color{background-color: var(--wp--preset--color--light-green-cyan) !important;}.has-vivid-green-cyan-background-color{background-color: var(--wp--preset--color--vivid-green-cyan) !important;}.has-pale-cyan-blue-background-color{background-color: var(--wp--preset--color--pale-cyan-blue) !important;}.has-vivid-cyan-blue-background-color{background-color: var(--wp--preset--color--vivid-cyan-blue) !important;}.has-vivid-purple-background-color{background-color: var(--wp--preset--color--vivid-purple) !important;}.has-black-border-color{border-color: var(--wp--preset--color--black) !important;}.has-cyan-bluish-gray-border-color{border-color: var(--wp--preset--color--cyan-bluish-gray) !important;}.has-white-border-color{border-color: var(--wp--preset--color--white) !important;}.has-pale-pink-border-color{border-color: var(--wp--preset--color--pale-pink) !important;}.has-vivid-red-border-color{border-color: var(--wp--preset--color--vivid-red) !important;}.has-luminous-vivid-orange-border-color{border-color: var(--wp--preset--color--luminous-vivid-orange) !important;}.has-luminous-vivid-amber-border-color{border-color: var(--wp--preset--color--luminous-vivid-amber) !important;}.has-light-green-cyan-border-color{border-color: var(--wp--preset--color--light-green-cyan) !important;}.has-vivid-green-cyan-border-color{border-color: var(--wp--preset--color--vivid-green-cyan) !important;}.has-pale-cyan-blue-border-color{border-color: var(--wp--preset--color--pale-cyan-blue) !important;}.has-vivid-cyan-blue-border-color{border-color: var(--wp--preset--color--vivid-cyan-blue) !important;}.has-vivid-purple-border-color{border-color: var(--wp--preset--color--vivid-purple) !important;}.has-vivid-cyan-blue-to-vivid-purple-gradient-background{background: var(--wp--preset--gradient--vivid-cyan-blue-to-vivid-purple) !important;}.has-light-green-cyan-to-vivid-green-cyan-gradient-background{background: var(--wp--preset--gradient--light-green-cyan-to-vivid-green-cyan) !important;}.has-luminous-vivid-amber-to-luminous-vivid-orange-gradient-background{background: var(--wp--preset--gradient--luminous-vivid-amber-to-luminous-vivid-orange) !important;}.has-luminous-vivid-orange-to-vivid-red-gradient-background{background: var(--wp--preset--gradient--luminous-vivid-orange-to-vivid-red) !important;}.has-very-light-gray-to-cyan-bluish-gray-gradient-background{background: var(--wp--preset--gradient--very-light-gray-to-cyan-bluish-gray) !important;}.has-cool-to-warm-spectrum-gradient-background{background: var(--wp--preset--gradient--cool-to-warm-spectrum) !important;}.has-blush-light-purple-gradient-background{background: var(--wp--preset--gradient--blush-light-purple) !important;}.has-blush-bordeaux-gradient-background{background: var(--wp--preset--gradient--blush-bordeaux) !important;}.has-luminous-dusk-gradient-background{background: var(--wp--preset--gradient--luminous-dusk) !important;}.has-pale-ocean-gradient-background{background: var(--wp--preset--gradient--pale-ocean) !important;}.has-electric-grass-gradient-background{background: var(--wp--preset--gradient--electric-grass) !important;}.has-midnight-gradient-background{background: var(--wp--preset--gradient--midnight) !important;}.has-small-font-size{font-size: var(--wp--preset--font-size--small) !important;}.has-medium-font-size{font-size: var(--wp--preset--font-size--medium) !important;}.has-large-font-size{font-size: var(--wp--preset--font-size--large) !important;}.has-x-large-font-size{font-size: var(--wp--preset--font-size--x-large) !important;} :where(.wp-block-post-template.is-layout-flex){gap: 1.25em;}:where(.wp-block-post-template.is-layout-grid){gap: 1.25em;} :where(.wp-block-columns.is-layout-flex){gap: 2em;}:where(.wp-block-columns.is-layout-grid){gap: 2em;} :root :where(.wp-block-pullquote){font-size: 1.5em;line-height: 1.6;} </style> <link rel='stylesheet' id='pb-accordion-blocks-style-css' href='https://www.sdss.org/wp-content/plugins/accordion-blocks/build/index.css?ver=1.5.0' media='all' /> <style id='darkmodetg-inline-css'> html{opacity:1}html.dmtg-fade{opacity:0;background:#000000}.darkmode--activated embed,.darkmode--activated iframe,.darkmode--activated img,.darkmode--activated video{filter:invert(100%)}.darkmode--activated embed:fullscreen,.darkmode--activated iframe:fullscreen,.darkmode--activated video:fullscreen{filter:invert(0%)}.darkmode--activated [style*="background-image: url"],.darkmode--activated [style*="background-image:url"]{filter:invert(100%)}.darkmode--activated .wp-block-cover[style*="background-image: url"] .wp-block-cover[style*="background-image: url"],.darkmode--activated .wp-block-cover[style*="background-image: url"] .wp-block-cover[style*="background-image:url"],.darkmode--activated .wp-block-cover[style*="background-image: url"] embed,.darkmode--activated .wp-block-cover[style*="background-image: url"] figure[class*=wp-duotone-],.darkmode--activated .wp-block-cover[style*="background-image: url"] iframe,.darkmode--activated .wp-block-cover[style*="background-image: url"] img,.darkmode--activated .wp-block-cover[style*="background-image: url"] video,.darkmode--activated .wp-block-cover[style*="background-image:url"] .wp-block-cover[style*="background-image: url"],.darkmode--activated .wp-block-cover[style*="background-image:url"] .wp-block-cover[style*="background-image:url"],.darkmode--activated .wp-block-cover[style*="background-image:url"] embed,.darkmode--activated .wp-block-cover[style*="background-image:url"] figure[class*=wp-duotone-],.darkmode--activated .wp-block-cover[style*="background-image:url"] iframe,.darkmode--activated .wp-block-cover[style*="background-image:url"] img,.darkmode--activated .wp-block-cover[style*="background-image:url"] video{filter:invert(0)}.darkmode--activated figure[class*=wp-duotone-]{filter:invert(1)}body.custom-background.darkmode--activated .darkmode-background{background:#fff;mix-blend-mode:difference}.darkmode--activated .stssm-social-icons{filter:invert(100%)}.darkmode--activated .dmt-filter-1{filter:invert(1)!important}.darkmode--activated .dmt-filter-0{filter:invert(0)!important} </style> <link rel='stylesheet' id='stssm-css' href='https://www.sdss.org/wp-content/plugins/share-social-media/assets/css/stssm.min.css?ver=1.5.9' media='all' /> <link rel='stylesheet' id='galaxis-style-css' href='https://www.sdss.org/wp-content/themes/galaxis/style.min.css?ver=1.8.3' media='all' /> <link rel='stylesheet' id='child-style-css' href='https://www.sdss.org/wp-content/themes/sdss_org_wp_theme/style.css?ver=1.1.2' media='all' /> <link rel='stylesheet' id='galaxis-fonts-css' href='https://www.sdss.org/wp-content/fonts/f6df4f4615a3a6dc50eed7bcc81f60ac.css' media='all' /> <script src="https://www.sdss.org/wp-content/plugins/google-analytics-for-wordpress/assets/js/frontend-gtag.min.js?ver=8.28.0" id="monsterinsights-frontend-script-js"></script> <script data-cfasync="false" data-wpfc-render="false" id='monsterinsights-frontend-script-js-extra'>var monsterinsights_frontend = {"js_events_tracking":"true","download_extensions":"doc,pdf,ppt,zip,xls,docx,pptx,xlsx","inbound_paths":"[{\"path\":\"\\\/go\\\/\",\"label\":\"affiliate\"},{\"path\":\"\\\/recommend\\\/\",\"label\":\"affiliate\"}]","home_url":"https:\/\/www.sdss.org","hash_tracking":"false","v4_id":"G-5BJ0FDW1X0"};</script> <script src="https://www.sdss.org/wp-includes/js/jquery/jquery.min.js?ver=3.7.1" id="jquery-core-js"></script> <script src="https://www.sdss.org/wp-includes/js/jquery/jquery-migrate.min.js?ver=3.4.1" id="jquery-migrate-js"></script> <script id="darkmodetg-fade-js-after"> ("true"===window.localStorage.darkmode)&&document.documentElement.classList.add("dmtg-fade"); </script> <script src="https://www.sdss.org/wp-content/plugins/wp-quicklatex/js/wp-quicklatex-frontend.js?ver=1.0" id="wp-quicklatex-frontend-js"></script> <link rel="https://api.w.org/" href="https://www.sdss.org/wp-json/" /><link rel="alternate" title="JSON" type="application/json" href="https://www.sdss.org/wp-json/wp/v2/posts/314" /><link rel="EditURI" type="application/rsd+xml" title="RSD" href="https://www.sdss.org/xmlrpc.php?rsd" /> <meta name="generator" content="WordPress 6.6" /> <link rel='shortlink' href='https://www.sdss.org/?p=314' /> <link rel="alternate" title="oEmbed (JSON)" type="application/json+oembed" href="https://www.sdss.org/wp-json/oembed/1.0/embed?url=https%3A%2F%2Fwww.sdss.org%2Fserving-up-the-universe-on-a-plate%2F" /> <link rel="alternate" title="oEmbed (XML)" type="text/xml+oembed" href="https://www.sdss.org/wp-json/oembed/1.0/embed?url=https%3A%2F%2Fwww.sdss.org%2Fserving-up-the-universe-on-a-plate%2F&format=xml" /> <style type="text/css">.broken_link, a.broken_link { text-decoration: line-through; }</style><style id="custom-background-css"> body.custom-background { background-color: #867dba; } </style> <link rel="icon" href="https://www.sdss.org/wp-content/uploads/2022/04/cropped-cropped-site_icon_SDSSV-32x32.png" sizes="32x32" /> <link rel="icon" href="https://www.sdss.org/wp-content/uploads/2022/04/cropped-cropped-site_icon_SDSSV-192x192.png" sizes="192x192" /> <link rel="apple-touch-icon" href="https://www.sdss.org/wp-content/uploads/2022/04/cropped-cropped-site_icon_SDSSV-180x180.png" /> <meta name="msapplication-TileImage" content="https://www.sdss.org/wp-content/uploads/2022/04/cropped-cropped-site_icon_SDSSV-270x270.png" /> <script src="https://kit.fontawesome.com/35ce0f3af3.js" crossorigin="anonymous"></script> <script type="text/javascript" src="/wp-content/plugins/sdss_wp_shortcodes/authorhider.js"></script> <script type="text/javascript" src="/wp-content/plugins/sdss_wp_shortcodes/vacsearch.js"></script> </head> <body class="post-template-default single single-post postid-314 single-format-standard custom-background wp-custom-logo wp-embed-responsive"> <div id="page" class="site"> <a class="skip-link screen-reader-text" href="#content">Skip to content</a> <header id="header" class="site-header"> <div class="site-topbar"> <div class="site-topbar__wrap wrapper"> <div class="site-topbar-text site-topbar__left"> <a href="/dr18/">Data Release 18</a> is here! </div> </div> </div> <div class="site-menu-content site-menu-content--sticky"> <div class="site-menu-content__wrap wrapper"> <div class="site-branding gx-no-branding-text"> <a href="https://www.sdss.org/" class="custom-logo-link" rel="home"><img width="252" height="117" src="https://www.sdss.org/wp-content/uploads/2022/09/sdss-new-logo-72dpi.png" class="custom-logo" alt="SDSS" decoding="async" /></a> </div> <nav id="site-navigation" class="main-navigation"> <button type="button" class="menu-button menu-toggle" aria-controls="primary-menu" aria-expanded="false"> <span class="screen-reader-text">Primary Menu</span> <span class="main-navigation__icon"> <span class="main-navigation__icon__middle"></span> </span> </button> <div class="primary-menu-container"><ul id="primary-menu" class="menu"><li itemscope="itemscope" itemtype="https://www.schema.org/SiteNavigationElement" id="menu-item-152" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-152 nav-item"><a title="Data" href="https://www.sdss.org/dr18/">Data</a></li> <li itemscope="itemscope" itemtype="https://www.schema.org/SiteNavigationElement" id="menu-item-153" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-has-children menu-item-153 nav-item"><a title="Mappers" href="https://www.sdss.org/mappers/" aria-expanded="false" id="menu-item-dropdown-153">Mappers</a><button type="button" class="menu-button menu-arrow-button"><span class="screen-reader-text menu-arrow-button-show">Expand Mappers submenu</span><span aria-hidden="true" class="screen-reader-text menu-arrow-button-hide">Collapse Mappers submenu</span><i class="sub-menu-arrow" aria-hidden="true"><svg class="svg-icon" width="20" height="20" aria-hidden="true" role="img" focusable="false" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M10 6L8.59 7.41 13.17 12l-4.58 4.59L10 18l6-6z"></path><path d="M0 0h24v24H0z" fill="none"></path></svg></i></button> <ul class="sub-menu"> <li itemscope="itemscope" itemtype="https://www.schema.org/SiteNavigationElement" id="menu-item-887" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-887 nav-item"><a title="About Milky Way Mapper" href="https://www.sdss.org/dr18/mwm/about/">About Milky Way Mapper</a></li> <li itemscope="itemscope" itemtype="https://www.schema.org/SiteNavigationElement" id="menu-item-885" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-885 nav-item"><a title="About Local Volume Mapper" href="https://www.sdss.org/dr18/lvm/about/">About Local Volume Mapper</a></li> <li itemscope="itemscope" itemtype="https://www.schema.org/SiteNavigationElement" id="menu-item-884" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-884 nav-item"><a title="About Black Hole Mapper" href="https://www.sdss.org/dr18/bhm/about/">About Black Hole Mapper</a></li> </ul> </li> <li itemscope="itemscope" itemtype="https://www.schema.org/SiteNavigationElement" id="menu-item-157" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-157 nav-item"><a title="Instruments" href="https://www.sdss.org/instruments/">Instruments</a></li> <li itemscope="itemscope" itemtype="https://www.schema.org/SiteNavigationElement" id="menu-item-158" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-158 nav-item"><a title="Collaboration" href="https://www.sdss.org/collaboration/">Collaboration</a></li> <li itemscope="itemscope" itemtype="https://www.schema.org/SiteNavigationElement" id="menu-item-159" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-has-children menu-item-159 nav-item"><a title="Science" href="https://www.sdss.org/science/" aria-expanded="false" id="menu-item-dropdown-159">Science</a><button type="button" class="menu-button menu-arrow-button"><span class="screen-reader-text menu-arrow-button-show">Expand Science submenu</span><span aria-hidden="true" class="screen-reader-text menu-arrow-button-hide">Collapse Science submenu</span><i class="sub-menu-arrow" aria-hidden="true"><svg class="svg-icon" width="20" height="20" aria-hidden="true" role="img" focusable="false" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M10 6L8.59 7.41 13.17 12l-4.58 4.59L10 18l6-6z"></path><path d="M0 0h24v24H0z" fill="none"></path></svg></i></button> <ul class="sub-menu"> <li itemscope="itemscope" itemtype="https://www.schema.org/SiteNavigationElement" id="menu-item-162" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-162 nav-item"><a title="Results" href="https://www.sdss.org/science/">Results</a></li> <li itemscope="itemscope" itemtype="https://www.schema.org/SiteNavigationElement" id="menu-item-3024" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-3024 nav-item"><a title="News" href="https://www.sdss.org/news/">News</a></li> <li itemscope="itemscope" itemtype="https://www.schema.org/SiteNavigationElement" id="menu-item-160" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-160 nav-item"><a title="Publications" href="https://www.sdss.org/science/publications/">Publications</a></li> <li itemscope="itemscope" itemtype="https://www.schema.org/SiteNavigationElement" id="menu-item-3030" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-3030 nav-item"><a title="Science Blog" href="https://www.sdss.org/blog/">Science Blog</a></li> </ul> </li> <li itemscope="itemscope" itemtype="https://www.schema.org/SiteNavigationElement" id="menu-item-161" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-161 nav-item"><a title="Education" href="https://www.sdss.org/education/">Education</a></li> <li itemscope="itemscope" itemtype="https://www.schema.org/SiteNavigationElement" id="menu-item-538" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-538 nav-item"><a title="Contact" href="https://www.sdss.org/contact-us/">Contact</a></li> </ul></div> </nav> </div> </div> <div id='breadsearch' class='wrapper'> <div class='gx-card-content'> <div class='crumbs'><ul><li><a href='/news/'>News</a></li></ul></div> <div class='searcher'><section id="block-3" class="widget widget_block widget_search"><form role="search" method="get" action="https://www.sdss.org/" class="wp-block-search__button-inside wp-block-search__icon-button wp-block-search" ><label class="wp-block-search__label screen-reader-text" for="wp-block-search__input-1" >Search</label><div class="wp-block-search__inside-wrapper " ><input class="wp-block-search__input" id="wp-block-search__input-1" placeholder="Search..." value="" type="search" name="s" required /><button aria-label="Search" class="wp-block-search__button has-icon wp-element-button" type="submit" ><svg class="search-icon" viewBox="0 0 24 24" width="24" height="24"> <path d="M13 5c-3.3 0-6 2.7-6 6 0 1.4.5 2.7 1.3 3.7l-3.8 3.8 1.1 1.1 3.8-3.8c1 .8 2.3 1.3 3.7 1.3 3.3 0 6-2.7 6-6S16.3 5 13 5zm0 10.5c-2.5 0-4.5-2-4.5-4.5s2-4.5 4.5-4.5 4.5 2 4.5 4.5-2 4.5-4.5 4.5z"></path> </svg></button></div></form></aside></div> </div> </div> </header> <div id="content" class="site-content"> <div class="wrapper u-t-margin"> <div class="columns columns--gutters"> <div id="primary" class="content-area columns__md-8 u-b-margin"> <main id="main" class="site-main"> <article id="post-314" class="gx-card u-b-margin post-314 post type-post status-publish format-standard hentry category-news"> <div class="gx-card-content"> <header class="entry-header"> <span class="cat-links"> <span class="screen-reader-text">Posted in:</span> <a href="https://www.sdss.org/category/news/" rel="category tag">News Releases</a> </span> <h1 class="entry-title">Serving up the Universe on a plate</h1> <div class="entry-meta"> <span class='pr-date'> <span class="posted-on"> <a href="https://www.sdss.org/serving-up-the-universe-on-a-plate/" rel="bookmark"> <time class="entry-date published" datetime="2021-07-13T18:26:00+00:00">July 13, 2021</time><time class="updated" datetime="2024-08-23T15:16:53+00:00">August 23, 2024</time> </a> </span> </span>  </div> </header> <div class="entry-content"> <div class="stssm-before-content"><ul class="stssm-social-icons stssm-content-social-icons"><li class="ssm-facebook"><i tabindex="0" role="button" class="ssm-fab ssm-fa-facebook-f" aria-label="Share on Facebook"></i></li><li class="ssm-reddit"><i tabindex="0" role="button" class="ssm-fab ssm-fa-reddit" aria-label="Share on Reddit"></i></li><li class="ssm-xtwitter"><i tabindex="0" role="button" class="ssm-fab ssm-fa-x-twitter" aria-label="Share on X (Twitter)"></i></li><li class="ssm-whatsapp"><i tabindex="0" role="button" class="ssm-fab ssm-fa-whatsapp" aria-label="Share on Whatsapp"></i></li><li class="ssm-envelope"><i tabindex="0" role="button" class="ssm-fas ssm-fa-envelope" aria-label="Share via Email"></i></li></ul></div><div class="wp-block-image"> <figure class="alignright size-large"><a href="/wp-content/uploads/2022/04/schlegel-fullsize.jpg"><img decoding="async" src="/wp-content/uploads/2022/04/schlegel.jpeg" alt="A man holds up an SDSS plate"/></a><figcaption class="wp-element-caption">David Schlegel, a key developer of SDSS’s spectroscopy program and the Principal Investigator of the SDSS-III BOSS survey, holds up a newly drilled plate. Click on the image for a larger version.<br><br><strong style="font-size: revert;">Image credit:</strong><span style="font-size: revert;"> Lawrence Berkeley National Laboratory</span> </figcaption></figure></div> <p>They may not look like much — just metal disks 80 centimeters (30 inches) across with some etched markings and hundreds of small holes — but round aluminum “plates” like this one from the Sloan Digital Sky Survey (SDSS) have been vital to mapping our universe for more than 20 years.</p> <p>“The light passing through these plates has helped us search for answers to an enormous range of questions that we want to ask about our Universe, from nearby stars and planetary systems to distant galaxies and giant black holes,” says Gail Zasowski, the scientific spokesperson for SDSS-V.</p> <p>The plates enabled the SDSS to use one of the most powerful techniques in astrophysics: splitting the light from an object up into the rainbow of its constituent colors to create a graph called a “spectrum,” which shows how much light of different energies the object emits.</p> <p>Studying the spectrum of a galaxy can tell us details like how far away it is, how long ago its stars formed, and even how those stars orbit the supermassive black hole at the galaxy’s center. The spectrum of the gas falling into that black hole can help us calculate how big the black hole is and how quickly it is growing. For an individual star, a spectrum can tell us its temperature, the chemical elements of which it is made, and how quickly it is moving towards or away from us. Multiple spectra of the same star over time can even be used to detect the presence of orbiting exoplanets or faint companions.</p> <div class="wp-block-image"> <figure class="alignleft size-large"><img decoding="async" src="/wp-content/uploads/2022/04/plate-photo-background.png" alt="Red lines overlaid on New York City, Toronto, Santiago, Munich, Shanghai, and Sydney"/><figcaption class="wp-element-caption">A plate from the SDSS-III BOSS survey, against a zoomed-in background of itself, showing the holes and the annotations used to help plug in the optical fibers. <br><br><strong style="font-size: revert;">Image credit:</strong><span style="font-size: revert;"> Sloan Digital Sky Survey</span> </figcaption></figure></div> <p>Astronomers have studied spectra of objects in the sky for centuries, but over time a problem appeared. Traditionally, astronomers relied on tiny slits in metal sheets to pass the light from single — or at most, a few — stars or galaxies into one spectrograph (a device that measures a spectrum), often a laborious process. As sky surveys got bigger and needed to collect spectra for more and more stars and galaxies, it became impractical to wait for spectrographs to collect all the data using these traditional methods. A new approach was needed.</p> <p>The solution came at the end of the 1990s, when astronomers and engineers from the SDSS began to drill hundreds of holes in large aluminum plates, each hole positioned to line up with a star or galaxy towards a particular patch of the sky as shown in this <a rel="noopener" href="https://www.youtube.com/watch?v=iYyO7pGaJNw" target="_blank">video of SDSS plates being drilled</a>. When the plate was set at the back of the telescope, an optical fiber, carefully plugged by hand into each hole as shown in this <a rel="noopener" href="https://www.youtube.com/watch?v=iYyO7pGaJNw" target="_blank">video of observers plugging fibers into an SDSS plate</a>, carried the light from the star or the galaxy into a spectrograph. This new system allowed several hundred spectra to be collected at the same time, dramatically increasing the speed at which objects in the sky could be measured.</p> <p>In fact, SDSS-IV Director Mike Blanton explains that “the very first batch of data we used in early 2000 was almost as big as any of the previous redshift surveys ever done, and that was just from the first month or two of observations!”</p> <figure class="wp-block-image size-large"><a href="/wp-content/uploads/2022/04/last_plate_at_telescope_fullsize.jpg"><img decoding="async" src="/wp-content/uploads/2022/04/last-plate-at-telescope.jpeg" alt="A round disk sits on the focal plane of a telescope"/></a><figcaption class="wp-element-caption">The final plate of the SDSS plate program sits at the base of the Sloan Telescope at the Apache Point Observatory in New Mexico, USA. The colored fibers visible below the plate have been plugged into their holes and will carry the light to the waiting instruments. <span style="font-size: revert;">Click on the image for a larger version.</span> <p><strong>Image credit:</strong> J. Burchett</p></figcaption></figure> <p>Since those early measurements, more than twelve thousand plates have been drilled, hand-plugged, and observed. That’s a lot of metal — if all of these plates were piled together, their combined weight would equal that of twelve African bull elephants — or, for astronomers, a cube of white dwarf star material just under 4 centimeters (one and a half inches) on each side. All those plates would contain enough metal to make 4.3 million soda cans. All of these plates were drilled by engineers at the University of Washington’s machine shop, and each hole in each plate was plugged in by hand by staff at one of the SDSS’s telescopes in New Mexico and Chile.</p> <p>The appearance of the plates has evolved over time, as the SDSS started new surveys, built new spectrographs, and even started using different telescopes. Many of the plates from recent years have more than one thousand holes each, or have holes for fibers from multiple spectrographs at the same time, or have holes that can accommodate bundles of dozens of optical fibers packed together. All told, more than 5.3 million individual holes have been drilled, each to within a tolerance of 10 micrometers (4 ten-thousandths of an inch). If you had to count all of these holes one-by-one, it would take you more than 60 straight days with no breaks.</p> <figure class="wp-block-image size-full"><a href="/wp-content/uploads/2022/04/plates-cities-fullsize.png"><img fetchpriority="high" decoding="async" width="800" height="1011" src="/wp-content/uploads/2022/04/plates-cities.png" alt="Red lines overlaid on New York City, Toronto, Santiago, Munich, Shanghai, and Sydney" class="wp-image-318" srcset="https://www.sdss.org/wp-content/uploads/2022/04/plates-cities.png 800w, https://www.sdss.org/wp-content/uploads/2022/04/plates-cities-237x300.png 237w, https://www.sdss.org/wp-content/uploads/2022/04/plates-cities-768x971.png 768w" sizes="(max-width: 800px) 100vw, 800px" /></a><figcaption class="wp-element-caption">If you placed all the SDSS plates end-to-end, they would stretch out for 13 km (8 miles). These maps show how far such a line of plates would stretch against six major world cities. Click on the image for a larger version. <br><br><strong>Image credit: </strong>Jordan Raddick (JHU), Niall Deacon (MPIA), and the Sloan Digital Sky Survey</figcaption></figure> <p>What have we learned from the photons that passed through all those holes? They comprise the spectra of over four million stars, galaxies, and quasars. In turn, these spectra have been used to measure how old the universe is, how much dark matter is in it, how its expansion is accelerating, and how its billions of galaxies formed and evolved over time. As SDSS continued observing over the years, it increasingly focused on the detailed history of our own Milky Way and nearby galaxies, and on how stars are born, evolve, die, and create the elements of which we ourselves are made. You can learn more about all the amazing results of the SDSS from <a href="#press">our list of press releases</a>.</p> <div class="wp-block-image"> <figure class="alignleft size-large"><a href="/wp-content/uploads/2022/04/TFitzpatrick_exhibit_fullsize_v2.jpg" target="_blank" rel="noopener"><img decoding="async" src="/wp-content/uploads/2022/04/TFitzpatrick_exhibit.jpeg" alt="A teacher shows a student an SDSS plug plate as part of a museum exhibit"/></a><figcaption class="wp-element-caption">Photo of an art exhibit by SDSS Artist-in-Residence Tim Fitzpatrick in St Andrews, Scotland in 2015. Volunteers and visitors examine a backlit SDSS plate on the left and art inspired by astronomical spectra on the right. <span style="font-size: revert;">Click on the image for a larger version.</span> <br><br><strong style="font-size: revert;">Image credit:</strong><span style="font-size: revert;"> T. Fitzpatrick</span> </figcaption></figure></div> <p>One of the best parts of all this information is that it is available any time to anyone, anywhere. “Every single spectrum observed by the SDSS is made available online, not just for astronomers, but for the whole world to study,” says Anne-Marie Weijmans, who oversees the effort to document and release these massive quantities of data. The enormous number of discoveries made using SDSS data have involved researchers all over the world, often asking questions or using the data in ways that were not even envisioned when the survey was designed.</p> <p>In addition to the vast scientific knowledge and online data troves enabled by this system, SDSS plates have provided a way for countless schoolchildren and members of the public to interact with real astronomical hardware and data. “To date, the SDSS’s <a rel="noopener" href="https://voyages.sdss.org/for-educators/sdss-plates-for-education/" target="_blank">Plates for Education</a> program has distributed several hundred plates — all of which have been used to observe the sky — to schools, museums, and other educational institutions around the world,” explains Romina Ahumada, who leads these SDSS educational efforts in Chile.</p> <div class="wp-block-columns contacts is-layout-flex wp-container-core-columns-is-layout-1 wp-block-columns-is-layout-flex"> <div class="wp-block-column is-layout-flow wp-block-column-is-layout-flow"> <h2 class="wp-block-heading">Contacts</h2> <p><a rel="noreferrer noopener" href="http://www.physics.utah.edu/~zasowski/" target="_blank">Gail Zasowski</a><br>Scientific Spokesperson, SDSS-V<br>University of Utah<br>+1 (801) 581-6901<br><a href="mailto:gail.zasowski@gmail.com">gail.zasowski@gmail.com</a> </p> <p><a rel="noreferrer noopener" href="https://as.nyu.edu/faculty/michael-blanton.html" target="_blank">Michael Blanton</a><br>Director, SDSS-IV<br>New York University<br>+1 (212) 998-7770<br><a href="mailto:blanton@physics.nyu.edu">blanton@physics.nyu.edu</a></p> <p>Anne-Marie Weijmans<br>SDSS-IV Data Coordinator<br>University of St Andrews<br>+44 (0)1334 462823<br><a href="mailto:amw23@st-andrews.ac.uk">amw23@st-andrews.ac.uk</a><br>Twitter: <a href="https://twitter.com/amweijmans">@AMWeijmans</a> / <a rel="noreferrer noopener" href="https://twitter.com/sdssurveys" target="_blank">@SDSSurveys</a></p> <p>Romina Ahumada<br>Instituto de Astronomía, Universidad Católica del Norte, Chile<br>+56 9 6674 5782<br><a href="mailto:rommy.ahumada@gmail.com">rommy.ahumada@gmail.com</a> </p> <p><a href="https://ctac.carnegiescience.edu/juna-kollmeier-founding-director">Juna Kollmeier</a><br>Director, SDSS-V<br>Carnegie Institution for Science<br>+1 (626) 304-0220<br><a href="mailto:jak@carnegiescience.edu">jak@carnegiescience.edu</a></p> </div> </div> <p>The Plates for Education program has developed materials to help everyone learn about the celestial objects observed with the very plate in their hands, and to help educators incorporate the plates into their curricula to teach numerous astrophysical concepts. To learn how these curricula work, watch <a rel="noopener" href="https://www.youtube.com/watch?v=WoU_0SO-Mnw" target="_blank">this online workshop given by SDSS astronomers Britt Lundgren and Gail Zasowski</a>.</p> <p>Artists around the world have also explored numerous aspects of the plates as windows to the universe, including <a href="http://whitespace.cn/artists/yang-jian/">Jian Yang</a> in Beijing, <a href="https://www.nytimes.com/slideshow/2012/06/17/arts/design/20120617-MCELHENY/s/20120617-MCELHENY-slide-3KXN.html">Josiah McElheny</a> in New York City (see also <a href="https://arxiv.org/pdf/1209.5113.pdf">this preprint describing his work</a>), and <a href="/press-releases/artist-in-residence/">SDSS’s own Artist-in-Residence Tim Fitzpatrick</a>.</p> <p>Now, after over two decades of using these plates to support its data collection (literally and metaphorically), the Sloan Digital Sky Survey is moving to a new era — one in which tiny robots will position each optical fiber to match the location of a star, galaxy, supermassive black hole, or other target. This is the perfect time to look back at the monumental scientific contribution of the plates, as the team plans for the next major developments that will be enabled by the new, even faster system.</p> <p>As Juna Kollmeier, the Director of the brand-new fifth phase of the SDSS project (SDSS-V), says, “The plates have been amazing. In graduate school, I worked with the first ones, and it’s humbling to think of all we have learned and all we still have to discover.”</p> <p>Although observations with the SDSS plates have now ended, the survey looks ahead to an even brighter future. SDSS-V observations have already begun, using a sophisticated system in which robots repeatedly arrange and rearrange the optical fibers, allowing far more objects to be observed in far shorter times. Kollmeier continues, “With SDSS-V and its robots, we will now be able to fully probe the entire sky with spectra, repeatedly in time, and make that data available to the world. How does the Universe change over days, weeks, or even years? We’ve had key snapshots of the universe — now it’s time to make the movie.”</p> <h2 class="wp-block-heading">Press Releases</h2> <p>All prior SDSS press releases can be found in the press release archives of the various phases of the SDSS:</p> <h3 class="wp-block-heading"><a rel="noopener" href="/press-releases/" target="_blank">SDSS-IV Press release archive</a></h3> <h3 class="wp-block-heading"><a rel="noopener" href="http://sdss3.org/press/" target="_blank">SDSS-III press release archive</a></h3> <h3 class="wp-block-heading"><a rel="noopener" href="http://classic.sdss.org/news/" target="_blank">SDSS-I/-II Press release archive</a></h3> <p>Acknowledgements</p> <p>Funding for the Sloan Digital Sky Survey V has been provided by the Alfred P. Sloan Foundation, the Heising-Simons Foundation, and the Participating Institutions. SDSS acknowledges support and resources from the Center for High-Performance Computing at the University of Utah.</p> <p>SDSS is managed by the Astrophysical Research Consortium for the Participating Institutions of the SDSS Collaboration, including the Carnegie Institution for Science, Chilean National Time Allocation Committee (CNTAC) ratified researchers, the Gotham Participation Group, Harvard University, The Johns Hopkins University, L’Ecole polytechnique fédérale de Lausanne (EPFL), Leibniz-Institut für Astrophysik Potsdam (AIP), Max-Planck-Institut für Astronomie (MPIA Heidelberg), Max-Planck-Institut für Extraterrestrische Physik (MPE), Nanjing University, National Astronomical Observatories of China (NAOC), New Mexico State University, The Ohio State University, Pennsylvania State University, Smithsonian Astrophysical Observatory, Space Telescope Science Institute (STScI), the Stellar Astrophysics Participation Group, Universidad Nacional Autónoma de México, University of Arizona, University of Colorado Boulder, University of Illinois at Urbana-Champaign, University of Toronto, University of Utah, University of Virginia, and Yale University.</p> <div class="stssm-after-content"><ul class="stssm-social-icons stssm-content-social-icons"><li class="ssm-facebook"><i tabindex="0" role="button" class="ssm-fab ssm-fa-facebook-f" aria-label="Share on Facebook"></i></li><li class="ssm-reddit"><i tabindex="0" role="button" class="ssm-fab ssm-fa-reddit" aria-label="Share on Reddit"></i></li><li class="ssm-xtwitter"><i tabindex="0" role="button" class="ssm-fab ssm-fa-x-twitter" aria-label="Share on X (Twitter)"></i></li><li class="ssm-whatsapp"><i tabindex="0" role="button" class="ssm-fab ssm-fa-whatsapp" aria-label="Share on Whatsapp"></i></li><li class="ssm-envelope"><i tabindex="0" role="button" class="ssm-fas ssm-fa-envelope" aria-label="Share via Email"></i></li></ul></div> </div> <footer class="entry-footer"> </footer> </div> </article> <nav class="navigation post-navigation" aria-label="Posts"> <h2 class="screen-reader-text">Post navigation</h2> <div class="nav-links"><div class="nav-previous"><a href="https://www.sdss.org/next-gen-astronomical-survey-makes-its-first-observations-toward-a-new-understanding-of-the-cosmos/" rel="prev"><div class="gx-card-content gx-card-content--same-md-y"><span class="meta-nav" aria-hidden="true">Previous Post</span> <span class="screen-reader-text">Previous post:</span> <br/><span class="post-title">Next-gen astronomical survey makes its first observations toward a new understanding of the cosmos</span></div></a></div><div class="nav-next"><a href="https://www.sdss.org/sdss-vs-robots-turn-their-eyes-to-the-sky/" rel="next"><div class="gx-card-content gx-card-content--same-md-y"><span class="meta-nav" aria-hidden="true">Next Post</span> <span class="screen-reader-text">Next post:</span> <br/><span class="post-title">SDSS-V’s Robots Turn their Eyes to the Sky</span></div></a></div></div> </nav> </main> </div> <div class="columns__md-4"> <div class="sidebar__inner"> <aside id="secondary" class="widget-area sidebar-1 h-center-upto-md" aria-label="Sidebar"> <section id="nav_menu-44" class="widget gx-card-content u-b-margin widget_nav_menu"><h3 class="widget-title">Science</h3><nav class="menu-science-container" aria-label="Science"><ul id="menu-science" class="menu"><li id="menu-item-182" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-182"><a href="https://www.sdss.org/science/">Science Results</a></li> <li id="menu-item-3029" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-3029"><a href="https://www.sdss.org/news/">News</a></li> <li id="menu-item-3422" class="menu-item menu-item-type-custom menu-item-object-custom menu-item-3422"><a href="https://blog.sdss.org">Science Blog</a></li> <li id="menu-item-2472" class="menu-item menu-item-type-custom menu-item-object-custom menu-item-has-children menu-item-2472"><a href="#"><span class='notlink'>Publications</span></a> <ul class="sub-menu"> <li id="menu-item-183" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-183"><a href="https://www.sdss.org/science/publications/">All Publications</a></li> <li id="menu-item-787" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-787"><a href="https://www.sdss.org/science/publications/data-release-publications/">Data Release Publications</a></li> <li id="menu-item-788" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-788"><a href="https://www.sdss.org/science/publications/technical-publications/">Technical Publications</a></li> </ul> </li> <li id="menu-item-3420" class="menu-item menu-item-type-custom menu-item-object-custom menu-item-has-children menu-item-3420"><a href="#"><span class='notlink'>Image Gallery</span></a> <ul class="sub-menu"> <li id="menu-item-3173" class="menu-item menu-item-type-custom menu-item-object-custom menu-item-3173"><a href="https://www.sdss4.org/science/image-gallery">SDSS-IV image gallery</a></li> <li id="menu-item-3421" class="menu-item menu-item-type-custom menu-item-object-custom menu-item-3421"><a href="https://classic.sdss.org/gallery/">SDSS Classic image gallery</a></li> </ul> </li> </ul></nav></aside><section id="nav_menu-7" class="widget gx-card-content u-b-margin widget_nav_menu"><h3 class="widget-title">Collaboration</h3><nav class="menu-collaboration-container" aria-label="Collaboration"><ul id="menu-collaboration" class="menu"><li id="menu-item-186" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-has-children menu-item-186"><a href="https://www.sdss.org/collaboration/">Overview</a> <ul class="sub-menu"> <li id="menu-item-1475" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-1475"><a href="https://www.sdss.org/collaboration/citing-sdss/">How to Cite SDSS</a></li> <li id="menu-item-1474" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-1474"><a href="https://www.sdss.org/collaboration/image-use-policy/">Image Use Policy</a></li> <li id="menu-item-187" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-187"><a href="https://www.sdss.org/collaboration/affiliate-institutions/">Affiliate Institutions</a></li> <li id="menu-item-188" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-188"><a href="https://www.sdss.org/collaboration/key-people/">Key People</a></li> <li id="menu-item-190" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-190"><a href="https://www.sdss.org/collaboration/architects/">Architects</a></li> <li id="menu-item-189" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-189"><a href="https://www.sdss.org/collaboration/the-sdss-science-collaboration-council/">Collaboration Council</a></li> <li id="menu-item-3427" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-3427"><a href="https://www.sdss.org/collaboration/the-sdss-advisory-council/">Advisory Council</a></li> <li id="menu-item-1476" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-1476"><a href="https://www.sdss.org/collaboration/coins/">Committee on Inclusiveness</a></li> </ul> </li> <li id="menu-item-3970" class="menu-item menu-item-type-custom menu-item-object-custom menu-item-3970"><a href="/people/">SDSS People</a></li> <li id="menu-item-194" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-has-children menu-item-194"><a href="https://www.sdss.org/collaboration/start-guide/">For SDSS-V Collaboration Members</a> <ul class="sub-menu"> <li id="menu-item-191" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-191"><a href="https://www.sdss.org/collaboration/code-of-conduct/">Code of Conduct</a></li> <li id="menu-item-192" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-192"><a href="https://www.sdss.org/collaboration/publication-policy/">Publication Policy</a></li> <li id="menu-item-193" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-193"><a href="https://www.sdss.org/collaboration/external-collaborator-policy/">External Collaborator Policy</a></li> <li id="menu-item-3938" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-3938"><a href="https://www.sdss.org/collaboration/start-guide/">Start Guide</a></li> </ul> </li> </ul></nav></section><section id="nav_menu-26" class="widget gx-card-content u-b-margin widget_nav_menu"><h3 class="widget-title">Science</h3><nav class="menu-science-container" aria-label="Science"><ul id="menu-science-1" class="menu"><li class="menu-item menu-item-type-post_type menu-item-object-page menu-item-182"><a href="https://www.sdss.org/science/">Science Results</a></li> <li class="menu-item menu-item-type-post_type menu-item-object-page menu-item-3029"><a href="https://www.sdss.org/news/">News</a></li> <li class="menu-item menu-item-type-custom menu-item-object-custom menu-item-3422"><a href="https://blog.sdss.org">Science Blog</a></li> <li class="menu-item menu-item-type-custom menu-item-object-custom menu-item-has-children menu-item-2472"><a href="#"><span class='notlink'>Publications</span></a> <ul class="sub-menu"> <li class="menu-item menu-item-type-post_type menu-item-object-page menu-item-183"><a href="https://www.sdss.org/science/publications/">All Publications</a></li> <li class="menu-item menu-item-type-post_type menu-item-object-page menu-item-787"><a href="https://www.sdss.org/science/publications/data-release-publications/">Data Release Publications</a></li> <li class="menu-item menu-item-type-post_type menu-item-object-page menu-item-788"><a href="https://www.sdss.org/science/publications/technical-publications/">Technical Publications</a></li> </ul> </li> <li class="menu-item menu-item-type-custom menu-item-object-custom menu-item-has-children menu-item-3420"><a href="#"><span class='notlink'>Image Gallery</span></a> <ul class="sub-menu"> <li class="menu-item menu-item-type-custom menu-item-object-custom menu-item-3173"><a href="https://www.sdss4.org/science/image-gallery">SDSS-IV image gallery</a></li> <li class="menu-item menu-item-type-custom menu-item-object-custom menu-item-3421"><a href="https://classic.sdss.org/gallery/">SDSS Classic image gallery</a></li> </ul> </li> </ul></nav></section>   </aside> </div> </div> </div> </div> </div> <footer id="footer" class="site-footer"> <div class="gx-footer-block-area"> <div class="wrapper"> <div class="entry-content"> <div class="wp-block-columns is-layout-flex wp-container-core-columns-is-layout-2 wp-block-columns-is-layout-flex"> <div class="wp-block-column footmenu is-layout-flow wp-block-column-is-layout-flow"> <h3 class="wp-block-heading footmenu-label">Explore</h3> <p><a href="/dr18/" data-type="page" data-id="36">Data Release 18</a></p> <p><a href="/dr18/data_access/" data-type="page" data-id="38">Data Access</a></p> <p><a href="/dr18/tutorials/" data-type="page" data-id="519">Tutorials</a></p> <p><a href="/dr18/data_access/value-added-catalogs/" data-type="page" data-id="505">Value Added Catalogs</a></p> </div> <div class="wp-block-column footmenu is-layout-flow wp-block-column-is-layout-flow"> <h3 class="wp-block-heading footmenu-label">Learn</h3> <p><a href="/mappers/" data-type="page" data-id="68">Mappers</a></p> <p><a href="/instruments/" data-type="page" data-id="77">Instruments</a></p> <p><a href="/education/" data-type="page" data-id="91">Education</a></p> <p><a href="/science/" data-type="page" data-id="87">Science</a></p> </div> <div class="wp-block-column footmenu is-layout-flow wp-block-column-is-layout-flow"> <h3 class="wp-block-heading footmenu-label">Connect</h3> <p><a href="/contact-us/" data-type="page" data-id="32">Contact Us</a></p> <p><a href="mailto:helpdesk@sdss.org" target="_blank" rel="noreferrer noopener">Email Helpdesk</a></p> <p><a href="https://www.facebook.com/SDSSurveys/" target="_blank" rel="noreferrer noopener" class="broken_link">Facebook</a></p> <p><a href="/people/" title="">SDSS People</a></p> </div> <div class="wp-block-column footlogos is-layout-flow wp-block-column-is-layout-flow"> <p class="has-text-align-center">SDSS is supported by:</p> <div class="wp-block-image img-responsive"> <figure class="aligncenter size-large"><a href="https://www.sloan.org" target="_blank" rel="noreferrer noopener"><img loading="lazy" decoding="async" width="1024" height="200" src="/wp-content/uploads/2022/06/Logo-2B-SMALL-Gold-Blue-1024x200.png" alt="Alfred P. Sloan Foundation logo" class="wp-image-428" srcset="https://www.sdss.org/wp-content/uploads/2022/06/Logo-2B-SMALL-Gold-Blue-1024x200.png 1024w, https://www.sdss.org/wp-content/uploads/2022/06/Logo-2B-SMALL-Gold-Blue-300x59.png 300w, https://www.sdss.org/wp-content/uploads/2022/06/Logo-2B-SMALL-Gold-Blue-768x150.png 768w, https://www.sdss.org/wp-content/uploads/2022/06/Logo-2B-SMALL-Gold-Blue-1536x300.png 1536w, https://www.sdss.org/wp-content/uploads/2022/06/Logo-2B-SMALL-Gold-Blue.png 1687w" sizes="(max-width: 1024px) 100vw, 1024px" /></a></figure></div> <div class="wp-block-image img-responsive"> <figure class="aligncenter size-large"><a href="https://www.hsfoundation.org" target="_blank" rel="noreferrer noopener"><img loading="lazy" decoding="async" width="1024" height="194" src="/wp-content/uploads/2022/06/HSF_logo_horiz_RGB_760px-1024x194.png" alt="Heising-Simons Foundation logo" class="wp-image-429" srcset="https://www.sdss.org/wp-content/uploads/2022/06/HSF_logo_horiz_RGB_760px-1024x194.png 1024w, https://www.sdss.org/wp-content/uploads/2022/06/HSF_logo_horiz_RGB_760px-300x57.png 300w, https://www.sdss.org/wp-content/uploads/2022/06/HSF_logo_horiz_RGB_760px-768x146.png 768w, https://www.sdss.org/wp-content/uploads/2022/06/HSF_logo_horiz_RGB_760px-1536x291.png 1536w, https://www.sdss.org/wp-content/uploads/2022/06/HSF_logo_horiz_RGB_760px-2048x389.png 2048w" sizes="(max-width: 1024px) 100vw, 1024px" /></a></figure></div> <div class="wp-block-image img-responsive"> <figure class="aligncenter size-thumbnail"><a href="https://www.nsf.gov" target="_blank" rel="noreferrer noopener"><img loading="lazy" decoding="async" width="150" height="150" src="/wp-content/uploads/2022/06/NSF_4-Color_bitmap_Logo-380px-150x150.png" alt="U.S. National Science Foundation logo" class="wp-image-431" srcset="https://www.sdss.org/wp-content/uploads/2022/06/NSF_4-Color_bitmap_Logo-380px-150x150.png 150w, https://www.sdss.org/wp-content/uploads/2022/06/NSF_4-Color_bitmap_Logo-380px-298x300.png 298w, https://www.sdss.org/wp-content/uploads/2022/06/NSF_4-Color_bitmap_Logo-380px.png 380w" sizes="(max-width: 150px) 100vw, 150px" /></a></figure></div></div> </div> </div> </div> </div> <div class="site-footer-section site-footer__text"> <div class="wrapper"> <div class="columns columns--gutters-large v-center-mdl"> <div class="columns__md-4 columns__md-4--larger"> <p class="copyright"> Copyright 2022 | Sloan Digital Sky Survey</p> </div> </div> </div> </div> </footer> <a href="#" class="back-to-top"><span class="screen-reader-text">Back to Top</span></a> </div> <style id='core-block-supports-inline-css'> .wp-container-core-columns-is-layout-1{flex-wrap:nowrap;}.wp-container-core-columns-is-layout-2{flex-wrap:nowrap;} </style> <script src="https://www.sdss.org/wp-content/plugins/accordion-blocks/js/accordion-blocks.min.js?ver=1.5.0" id="pb-accordion-blocks-frontend-script-js"></script> <script src="https://www.sdss.org/wp-content/plugins/dark-mode-toggle/assets/js/darkmode-js.min.js?ver=1.4.5" id="darkmode-js-js"></script> <script id="darkmodetg-js-extra"> var darkmodetg = {"config":{"bottom":"32px","left":"32px","top":"unset","right":"unset","width":"44px","height":"44px","borderRadius":"44px","fontSize":"16px","time":"0s","backgroundColor":"transparent","buttonColorDark":"#333333","buttonColorLight":"#b3b3b3","buttonColorTDark":"#ffffff","buttonColorTLight":"#000000","saveInCookies":"1","fixFlick":"1","label":"🔥","autoMatchOsTheme":false,"buttonAriaLabel":"Toggle dark mode","overrideStyles":""}}; </script> <script src="https://www.sdss.org/wp-content/plugins/dark-mode-toggle/assets/js/dmtg.min.js?ver=1.4.5" id="darkmodetg-js"></script> <script id="stssm-js-extra"> var stssm = {"sticky":"0","title":"Serving up the Universe on a plate","desc":"They may not look like much \u2014 just metal disks 80 centimeters (30 inches) across with some etched markings and hundreds of small holes \u2014 but round aluminum \u201cplates\u201d like this one from the Sloan Digital Sky Survey (SDSS) have been vital to mapping our universe for more than 20 years. \u201cThe light passing through [...] <p class=\"more-link-container\"><a href=\"https:\/\/www.sdss.org\/serving-up-the-universe-on-a-plate\/\" class=\"more-link\">Read More<span class=\"screen-reader-text\"> \"Serving up the Universe on a plate\"<\/span><\/a><\/p>","image":"https:\/\/www.sdss.org\/wp-content\/uploads\/2022\/09\/sdss-new-logo-72dpi.png"}; </script> <script src="https://www.sdss.org/wp-content/plugins/share-social-media/assets/js/stssm.min.js?ver=1.5.9" id="stssm-js"></script> <script src="https://www.sdss.org/wp-content/themes/galaxis/js/script.min.js?ver=1.8.3" id="galaxis-script-js"></script> <script src="https://www.sdss.org/wp-content/themes/galaxis/js/ResizeObserver.min.js?ver=1.5.1" id="resize-observer-polyfill-js"></script> <script src="https://www.sdss.org/wp-content/themes/galaxis/js/sticky-sidebar.min.js?ver=1.1.1" id="sticky-sidebar-js"></script> <script id="sticky-sidebar-js-after"> try{new StickySidebar(".site-content > .wrapper > .columns > .columns__md-4",{topSpacing:100,bottomSpacing:0,containerSelector:".site-content > .wrapper > .columns",innerWrapperSelector:".sidebar__inner",minWidth:799});}catch(e){} </script> </body> </html>