nist-gov/www.nist.gov/blogs/taking-measure/top-nist-images-2018
2025-03-05 18:59:57 +00:00

1656 lines
119 KiB
Text
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

<!DOCTYPE html>
<html lang="en" dir="ltr" prefix="content: http://purl.org/rss/1.0/modules/content/ dc: http://purl.org/dc/terms/ foaf: http://xmlns.com/foaf/0.1/ og: http://ogp.me/ns# rdfs: http://www.w3.org/2000/01/rdf-schema# schema: http://schema.org/ sioc: http://rdfs.org/sioc/ns# sioct: http://rdfs.org/sioc/types# skos: http://www.w3.org/2004/02/skos/core# xsd: http://www.w3.org/2001/XMLSchema# ">
<head>
<meta charset="utf-8" /><script type="text/javascript">(window.NREUM||(NREUM={})).init={ajax:{deny_list:["bam.nr-data.net"]}};(window.NREUM||(NREUM={})).loader_config={licenseKey:"37b7ccb661",applicationID:"1089704227"};;/*! For license information please see nr-loader-rum-1.283.2.min.js.LICENSE.txt */
(()=>{var e,t,r={122:(e,t,r)=>{"use strict";r.d(t,{a:()=>i});var n=r(944);function i(e,t){try{if(!e||"object"!=typeof e)return(0,n.R)(3);if(!t||"object"!=typeof t)return(0,n.R)(4);const r=Object.create(Object.getPrototypeOf(t),Object.getOwnPropertyDescriptors(t)),o=0===Object.keys(r).length?e:r;for(let a in o)if(void 0!==e[a])try{if(null===e[a]){r[a]=null;continue}Array.isArray(e[a])&&Array.isArray(t[a])?r[a]=Array.from(new Set([...e[a],...t[a]])):"object"==typeof e[a]&&"object"==typeof t[a]?r[a]=i(e[a],t[a]):r[a]=e[a]}catch(e){(0,n.R)(1,e)}return r}catch(e){(0,n.R)(2,e)}}},555:(e,t,r)=>{"use strict";r.d(t,{Vp:()=>c,fn:()=>s,x1:()=>u});var n=r(384),i=r(122);const o={beacon:n.NT.beacon,errorBeacon:n.NT.errorBeacon,licenseKey:void 0,applicationID:void 0,sa:void 0,queueTime:void 0,applicationTime:void 0,ttGuid:void 0,user:void 0,account:void 0,product:void 0,extra:void 0,jsAttributes:{},userAttributes:void 0,atts:void 0,transactionName:void 0,tNamePlain:void 0},a={};function s(e){try{const t=c(e);return!!t.licenseKey&&!!t.errorBeacon&&!!t.applicationID}catch(e){return!1}}function c(e){if(!e)throw new Error("All info objects require an agent identifier!");if(!a[e])throw new Error("Info for ".concat(e," was never set"));return a[e]}function u(e,t){if(!e)throw new Error("All info objects require an agent identifier!");a[e]=(0,i.a)(t,o);const r=(0,n.nY)(e);r&&(r.info=a[e])}},217:(e,t,r)=>{"use strict";r.d(t,{D0:()=>m,gD:()=>v,xN:()=>h});r(860).K7.genericEvents;const n="experimental.marks",i="experimental.measures",o="experimental.resources",a=e=>{if(!e||"string"!=typeof e)return!1;try{document.createDocumentFragment().querySelector(e)}catch{return!1}return!0};var s=r(614),c=r(944),u=r(384),l=r(122);const d="[data-nr-mask]",f=()=>{const e={feature_flags:[],experimental:{marks:!1,measures:!1,resources:!1},mask_selector:"*",block_selector:"[data-nr-block]",mask_input_options:{color:!1,date:!1,"datetime-local":!1,email:!1,month:!1,number:!1,range:!1,search:!1,tel:!1,text:!1,time:!1,url:!1,week:!1,textarea:!1,select:!1,password:!0}};return{ajax:{deny_list:void 0,block_internal:!0,enabled:!0,autoStart:!0},distributed_tracing:{enabled:void 0,exclude_newrelic_header:void 0,cors_use_newrelic_header:void 0,cors_use_tracecontext_headers:void 0,allowed_origins:void 0},get feature_flags(){return e.feature_flags},set feature_flags(t){e.feature_flags=t},generic_events:{enabled:!0,autoStart:!0},harvest:{interval:30},jserrors:{enabled:!0,autoStart:!0},logging:{enabled:!0,autoStart:!0},metrics:{enabled:!0,autoStart:!0},obfuscate:void 0,page_action:{enabled:!0},page_view_event:{enabled:!0,autoStart:!0},page_view_timing:{enabled:!0,autoStart:!0},performance:{get capture_marks(){return e.feature_flags.includes(n)||e.experimental.marks},set capture_marks(t){e.experimental.marks=t},get capture_measures(){return e.feature_flags.includes(i)||e.experimental.measures},set capture_measures(t){e.experimental.measures=t},capture_detail:!0,resources:{get enabled(){return e.feature_flags.includes(o)||e.experimental.resources},set enabled(t){e.experimental.resources=t},asset_types:[],first_party_domains:[],ignore_newrelic:!0}},privacy:{cookies_enabled:!0},proxy:{assets:void 0,beacon:void 0},session:{expiresMs:s.wk,inactiveMs:s.BB},session_replay:{autoStart:!0,enabled:!1,preload:!1,sampling_rate:10,error_sampling_rate:100,collect_fonts:!1,inline_images:!1,fix_stylesheets:!0,mask_all_inputs:!0,get mask_text_selector(){return e.mask_selector},set mask_text_selector(t){a(t)?e.mask_selector="".concat(t,",").concat(d):""===t||null===t?e.mask_selector=d:(0,c.R)(5,t)},get block_class(){return"nr-block"},get ignore_class(){return"nr-ignore"},get mask_text_class(){return"nr-mask"},get block_selector(){return e.block_selector},set block_selector(t){a(t)?e.block_selector+=",".concat(t):""!==t&&(0,c.R)(6,t)},get mask_input_options(){return e.mask_input_options},set mask_input_options(t){t&&"object"==typeof t?e.mask_input_options={...t,password:!0}:(0,c.R)(7,t)}},session_trace:{enabled:!0,autoStart:!0},soft_navigations:{enabled:!0,autoStart:!0},spa:{enabled:!0,autoStart:!0},ssl:void 0,user_actions:{enabled:!0,elementAttributes:["id","className","tagName","type"]}}},g={},p="All configuration objects require an agent identifier!";function m(e){if(!e)throw new Error(p);if(!g[e])throw new Error("Configuration for ".concat(e," was never set"));return g[e]}function h(e,t){if(!e)throw new Error(p);g[e]=(0,l.a)(t,f());const r=(0,u.nY)(e);r&&(r.init=g[e])}function v(e,t){if(!e)throw new Error(p);var r=m(e);if(r){for(var n=t.split("."),i=0;i<n.length-1;i++)if("object"!=typeof(r=r[n[i]]))return;r=r[n[n.length-1]]}return r}},371:(e,t,r)=>{"use strict";r.d(t,{V:()=>f,f:()=>d});var n=r(122),i=r(384),o=r(154),a=r(324);let s=0;const c={buildEnv:a.F3,distMethod:a.Xs,version:a.xv,originTime:o.WN},u={customTransaction:void 0,disabled:!1,isolatedBacklog:!1,loaderType:void 0,maxBytes:3e4,onerror:void 0,ptid:void 0,releaseIds:{},appMetadata:{},session:void 0,denyList:void 0,timeKeeper:void 0,obfuscator:void 0,harvester:void 0},l={};function d(e){if(!e)throw new Error("All runtime objects require an agent identifier!");if(!l[e])throw new Error("Runtime for ".concat(e," was never set"));return l[e]}function f(e,t){if(!e)throw new Error("All runtime objects require an agent identifier!");l[e]={...(0,n.a)(t,u),...c},Object.hasOwnProperty.call(l[e],"harvestCount")||Object.defineProperty(l[e],"harvestCount",{get:()=>++s});const r=(0,i.nY)(e);r&&(r.runtime=l[e])}},324:(e,t,r)=>{"use strict";r.d(t,{F3:()=>i,Xs:()=>o,xv:()=>n});const n="1.283.2",i="PROD",o="CDN"},154:(e,t,r)=>{"use strict";r.d(t,{OF:()=>c,RI:()=>i,WN:()=>l,bv:()=>o,gm:()=>a,mw:()=>s,sb:()=>u});var n=r(863);const i="undefined"!=typeof window&&!!window.document,o="undefined"!=typeof WorkerGlobalScope&&("undefined"!=typeof self&&self instanceof WorkerGlobalScope&&self.navigator instanceof WorkerNavigator||"undefined"!=typeof globalThis&&globalThis instanceof WorkerGlobalScope&&globalThis.navigator instanceof WorkerNavigator),a=i?window:"undefined"!=typeof WorkerGlobalScope&&("undefined"!=typeof self&&self instanceof WorkerGlobalScope&&self||"undefined"!=typeof globalThis&&globalThis instanceof WorkerGlobalScope&&globalThis),s=Boolean("hidden"===a?.document?.visibilityState),c=/iPad|iPhone|iPod/.test(a.navigator?.userAgent),u=c&&"undefined"==typeof SharedWorker,l=((()=>{const e=a.navigator?.userAgent?.match(/Firefox[/\s](\d+\.\d+)/);Array.isArray(e)&&e.length>=2&&e[1]})(),Date.now()-(0,n.t)())},687:(e,t,r)=>{"use strict";r.d(t,{Ak:()=>c,Ze:()=>d,x3:()=>u});var n=r(836),i=r(606),o=r(860),a=r(646);const s={};function c(e,t){const r={staged:!1,priority:o.P3[t]||0};l(e),s[e].get(t)||s[e].set(t,r)}function u(e,t){e&&s[e]&&(s[e].get(t)&&s[e].delete(t),g(e,t,!1),s[e].size&&f(e))}function l(e){if(!e)throw new Error("agentIdentifier required");s[e]||(s[e]=new Map)}function d(e="",t="feature",r=!1){if(l(e),!e||!s[e].get(t)||r)return g(e,t);s[e].get(t).staged=!0,f(e)}function f(e){const t=Array.from(s[e]);t.every((([e,t])=>t.staged))&&(t.sort(((e,t)=>e[1].priority-t[1].priority)),t.forEach((([t])=>{s[e].delete(t),g(e,t)})))}function g(e,t,r=!0){const o=e?n.ee.get(e):n.ee,s=i.i.handlers;if(!o.aborted&&o.backlog&&s){if(r){const e=o.backlog[t],r=s[t];if(r){for(let t=0;e&&t<e.length;++t)p(e[t],r);Object.entries(r).forEach((([e,t])=>{Object.values(t||{}).forEach((t=>{t[0]?.on&&t[0]?.context()instanceof a.y&&t[0].on(e,t[1])}))}))}}o.isolatedBacklog||delete s[t],o.backlog[t]=null,o.emit("drain-"+t,[])}}function p(e,t){var r=e[1];Object.values(t[r]||{}).forEach((t=>{var r=e[0];if(t[0]===r){var n=t[1],i=e[3],o=e[2];n.apply(i,o)}}))}},836:(e,t,r)=>{"use strict";r.d(t,{P:()=>c,ee:()=>u});var n=r(384),i=r(990),o=r(371),a=r(646),s=r(607);const c="nr@context:".concat(s.W),u=function e(t,r){var n={},s={},l={},d=!1;try{d=16===r.length&&(0,o.f)(r).isolatedBacklog}catch(e){}var f={on:p,addEventListener:p,removeEventListener:function(e,t){var r=n[e];if(!r)return;for(var i=0;i<r.length;i++)r[i]===t&&r.splice(i,1)},emit:function(e,r,n,i,o){!1!==o&&(o=!0);if(u.aborted&&!i)return;t&&o&&t.emit(e,r,n);for(var a=g(n),c=m(e),l=c.length,d=0;d<l;d++)c[d].apply(a,r);var p=v()[s[e]];p&&p.push([f,e,r,a]);return a},get:h,listeners:m,context:g,buffer:function(e,t){const r=v();if(t=t||"feature",f.aborted)return;Object.entries(e||{}).forEach((([e,n])=>{s[n]=t,t in r||(r[t]=[])}))},abort:function(){f._aborted=!0,Object.keys(f.backlog).forEach((e=>{delete f.backlog[e]}))},isBuffering:function(e){return!!v()[s[e]]},debugId:r,backlog:d?{}:t&&"object"==typeof t.backlog?t.backlog:{},isolatedBacklog:d};return Object.defineProperty(f,"aborted",{get:()=>{let e=f._aborted||!1;return e||(t&&(e=t.aborted),e)}}),f;function g(e){return e&&e instanceof a.y?e:e?(0,i.I)(e,c,(()=>new a.y(c))):new a.y(c)}function p(e,t){n[e]=m(e).concat(t)}function m(e){return n[e]||[]}function h(t){return l[t]=l[t]||e(f,t)}function v(){return f.backlog}}(void 0,"globalEE"),l=(0,n.Zm)();l.ee||(l.ee=u)},646:(e,t,r)=>{"use strict";r.d(t,{y:()=>n});class n{constructor(e){this.contextId=e}}},908:(e,t,r)=>{"use strict";r.d(t,{d:()=>n,p:()=>i});var n=r(836).ee.get("handle");function i(e,t,r,i,o){o?(o.buffer([e],i),o.emit(e,t,r)):(n.buffer([e],i),n.emit(e,t,r))}},606:(e,t,r)=>{"use strict";r.d(t,{i:()=>o});var n=r(908);o.on=a;var i=o.handlers={};function o(e,t,r,o){a(o||n.d,i,e,t,r)}function a(e,t,r,i,o){o||(o="feature"),e||(e=n.d);var a=t[o]=t[o]||{};(a[r]=a[r]||[]).push([e,i])}},878:(e,t,r)=>{"use strict";function n(e,t){return{capture:e,passive:!1,signal:t}}function i(e,t,r=!1,i){window.addEventListener(e,t,n(r,i))}function o(e,t,r=!1,i){document.addEventListener(e,t,n(r,i))}r.d(t,{DD:()=>o,jT:()=>n,sp:()=>i})},607:(e,t,r)=>{"use strict";r.d(t,{W:()=>n});const n=(0,r(566).bz)()},566:(e,t,r)=>{"use strict";r.d(t,{LA:()=>s,bz:()=>a});var n=r(154);const i="xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx";function o(e,t){return e?15&e[t]:16*Math.random()|0}function a(){const e=n.gm?.crypto||n.gm?.msCrypto;let t,r=0;return e&&e.getRandomValues&&(t=e.getRandomValues(new Uint8Array(30))),i.split("").map((e=>"x"===e?o(t,r++).toString(16):"y"===e?(3&o()|8).toString(16):e)).join("")}function s(e){const t=n.gm?.crypto||n.gm?.msCrypto;let r,i=0;t&&t.getRandomValues&&(r=t.getRandomValues(new Uint8Array(e)));const a=[];for(var s=0;s<e;s++)a.push(o(r,i++).toString(16));return a.join("")}},614:(e,t,r)=>{"use strict";r.d(t,{BB:()=>a,H3:()=>n,g:()=>u,iL:()=>c,tS:()=>s,uh:()=>i,wk:()=>o});const n="NRBA",i="SESSION",o=144e5,a=18e5,s={STARTED:"session-started",PAUSE:"session-pause",RESET:"session-reset",RESUME:"session-resume",UPDATE:"session-update"},c={SAME_TAB:"same-tab",CROSS_TAB:"cross-tab"},u={OFF:0,FULL:1,ERROR:2}},863:(e,t,r)=>{"use strict";function n(){return Math.floor(performance.now())}r.d(t,{t:()=>n})},944:(e,t,r)=>{"use strict";function n(e,t){"function"==typeof console.debug&&console.debug("New Relic Warning: https://github.com/newrelic/newrelic-browser-agent/blob/main/docs/warning-codes.md#".concat(e),t)}r.d(t,{R:()=>n})},284:(e,t,r)=>{"use strict";r.d(t,{t:()=>c,B:()=>s});var n=r(836),i=r(154);const o="newrelic";const a=new Set,s={};function c(e,t){const r=n.ee.get(t);s[t]??={},e&&"object"==typeof e&&(a.has(t)||(r.emit("rumresp",[e]),s[t]=e,a.add(t),function(e={}){try{i.gm.dispatchEvent(new CustomEvent(o,{detail:e}))}catch(e){}}({loaded:!0})))}},990:(e,t,r)=>{"use strict";r.d(t,{I:()=>i});var n=Object.prototype.hasOwnProperty;function i(e,t,r){if(n.call(e,t))return e[t];var i=r();if(Object.defineProperty&&Object.keys)try{return Object.defineProperty(e,t,{value:i,writable:!0,enumerable:!1}),i}catch(e){}return e[t]=i,i}},389:(e,t,r)=>{"use strict";function n(e,t=500,r={}){const n=r?.leading||!1;let i;return(...r)=>{n&&void 0===i&&(e.apply(this,r),i=setTimeout((()=>{i=clearTimeout(i)}),t)),n||(clearTimeout(i),i=setTimeout((()=>{e.apply(this,r)}),t))}}function i(e){let t=!1;return(...r)=>{t||(t=!0,e.apply(this,r))}}r.d(t,{J:()=>i,s:()=>n})},289:(e,t,r)=>{"use strict";r.d(t,{GG:()=>o,sB:()=>a});var n=r(878);function i(){return"undefined"==typeof document||"complete"===document.readyState}function o(e,t){if(i())return e();(0,n.sp)("load",e,t)}function a(e){if(i())return e();(0,n.DD)("DOMContentLoaded",e)}},384:(e,t,r)=>{"use strict";r.d(t,{NT:()=>o,US:()=>l,Zm:()=>a,bQ:()=>c,dV:()=>s,nY:()=>u,pV:()=>d});var n=r(154),i=r(863);const o={beacon:"bam.nr-data.net",errorBeacon:"bam.nr-data.net"};function a(){return n.gm.NREUM||(n.gm.NREUM={}),void 0===n.gm.newrelic&&(n.gm.newrelic=n.gm.NREUM),n.gm.NREUM}function s(){let e=a();return e.o||(e.o={ST:n.gm.setTimeout,SI:n.gm.setImmediate,CT:n.gm.clearTimeout,XHR:n.gm.XMLHttpRequest,REQ:n.gm.Request,EV:n.gm.Event,PR:n.gm.Promise,MO:n.gm.MutationObserver,FETCH:n.gm.fetch,WS:n.gm.WebSocket}),e}function c(e,t){let r=a();r.initializedAgents??={},t.initializedAt={ms:(0,i.t)(),date:new Date},r.initializedAgents[e]=t}function u(e){let t=a();return t.initializedAgents?.[e]}function l(e,t){a()[e]=t}function d(){return function(){let e=a();const t=e.info||{};e.info={beacon:o.beacon,errorBeacon:o.errorBeacon,...t}}(),function(){let e=a();const t=e.init||{};e.init={...t}}(),s(),function(){let e=a();const t=e.loader_config||{};e.loader_config={...t}}(),a()}},843:(e,t,r)=>{"use strict";r.d(t,{u:()=>i});var n=r(878);function i(e,t=!1,r,i){(0,n.DD)("visibilitychange",(function(){if(t)return void("hidden"===document.visibilityState&&e());e(document.visibilityState)}),r,i)}},434:(e,t,r)=>{"use strict";r.d(t,{Jt:()=>o,YM:()=>c});var n=r(836),i=r(607);const o="nr@original:".concat(i.W);var a=Object.prototype.hasOwnProperty,s=!1;function c(e,t){return e||(e=n.ee),r.inPlace=function(e,t,n,i,o){n||(n="");const a="-"===n.charAt(0);for(let s=0;s<t.length;s++){const c=t[s],u=e[c];l(u)||(e[c]=r(u,a?c+n:n,i,c,o))}},r.flag=o,r;function r(t,r,n,s,c){return l(t)?t:(r||(r=""),nrWrapper[o]=t,function(e,t,r){if(Object.defineProperty&&Object.keys)try{return Object.keys(e).forEach((function(r){Object.defineProperty(t,r,{get:function(){return e[r]},set:function(t){return e[r]=t,t}})})),t}catch(e){u([e],r)}for(var n in e)a.call(e,n)&&(t[n]=e[n])}(t,nrWrapper,e),nrWrapper);function nrWrapper(){var o,a,l,d;try{a=this,o=[...arguments],l="function"==typeof n?n(o,a):n||{}}catch(t){u([t,"",[o,a,s],l],e)}i(r+"start",[o,a,s],l,c);try{return d=t.apply(a,o)}catch(e){throw i(r+"err",[o,a,e],l,c),e}finally{i(r+"end",[o,a,d],l,c)}}}function i(r,n,i,o){if(!s||t){var a=s;s=!0;try{e.emit(r,n,i,t,o)}catch(t){u([t,r,n,i],e)}s=a}}}function u(e,t){t||(t=n.ee);try{t.emit("internal-error",e)}catch(e){}}function l(e){return!(e&&"function"==typeof e&&e.apply&&!e[o])}},993:(e,t,r)=>{"use strict";r.d(t,{A$:()=>o,ET:()=>a,p_:()=>i});var n=r(860);const i={ERROR:"ERROR",WARN:"WARN",INFO:"INFO",DEBUG:"DEBUG",TRACE:"TRACE"},o={OFF:0,ERROR:1,WARN:2,INFO:3,DEBUG:4,TRACE:5},a="log";n.K7.logging},773:(e,t,r)=>{"use strict";r.d(t,{z_:()=>o,XG:()=>s,TZ:()=>n,rs:()=>i,xV:()=>a});r(154),r(566),r(384);const n=r(860).K7.metrics,i="sm",o="cm",a="storeSupportabilityMetrics",s="storeEventMetrics"},630:(e,t,r)=>{"use strict";r.d(t,{T:()=>n});const n=r(860).K7.pageViewEvent},782:(e,t,r)=>{"use strict";r.d(t,{T:()=>n});const n=r(860).K7.pageViewTiming},344:(e,t,r)=>{"use strict";r.d(t,{G4:()=>i});var n=r(614);r(860).K7.sessionReplay;const i={RECORD:"recordReplay",PAUSE:"pauseReplay",REPLAY_RUNNING:"replayRunning",ERROR_DURING_REPLAY:"errorDuringReplay"};n.g.ERROR,n.g.FULL,n.g.OFF},234:(e,t,r)=>{"use strict";r.d(t,{W:()=>o});var n=r(836),i=r(687);class o{constructor(e,t){this.agentIdentifier=e,this.ee=n.ee.get(e),this.featureName=t,this.blocked=!1}deregisterDrain(){(0,i.x3)(this.agentIdentifier,this.featureName)}}},603:(e,t,r)=>{"use strict";r.d(t,{j:()=>K});var n=r(860),i=r(555),o=r(371),a=r(908),s=r(836),c=r(687),u=r(289),l=r(154),d=r(944),f=r(773),g=r(384),p=r(344);const m=["setErrorHandler","finished","addToTrace","addRelease","recordCustomEvent","addPageAction","setCurrentRouteName","setPageViewName","setCustomAttribute","interaction","noticeError","setUserId","setApplicationVersion","start",p.G4.RECORD,p.G4.PAUSE,"log","wrapLogger"],h=["setErrorHandler","finished","addToTrace","addRelease"];var v=r(863),b=r(614),y=r(993);var w=r(646),R=r(434);const A=new Map;function E(e,t,r,n){if("object"!=typeof t||!t||"string"!=typeof r||!r||"function"!=typeof t[r])return(0,d.R)(29);const i=function(e){return(e||s.ee).get("logger")}(e),o=(0,R.YM)(i),a=new w.y(s.P);a.level=n.level,a.customAttributes=n.customAttributes;const c=t[r]?.[R.Jt]||t[r];return A.set(c,a),o.inPlace(t,[r],"wrap-logger-",(()=>A.get(c))),i}function _(){const e=(0,g.pV)();m.forEach((t=>{e[t]=(...r)=>function(t,...r){let n=[];return Object.values(e.initializedAgents).forEach((e=>{e&&e.api?e.exposed&&e.api[t]&&n.push(e.api[t](...r)):(0,d.R)(38,t)})),n.length>1?n:n[0]}(t,...r)}))}const x={};function N(e,t,g=!1){t||(0,c.Ak)(e,"api");const m={};var w=s.ee.get(e),R=w.get("tracer");x[e]=b.g.OFF,w.on(p.G4.REPLAY_RUNNING,(t=>{x[e]=t}));var A="api-",_=A+"ixn-";function N(t,r,n,o){const a=(0,i.Vp)(e);return null===r?delete a.jsAttributes[t]:(0,i.x1)(e,{...a,jsAttributes:{...a.jsAttributes,[t]:r}}),j(A,n,!0,o||null===r?"session":void 0)(t,r)}function k(){}m.log=function(e,{customAttributes:t={},level:r=y.p_.INFO}={}){(0,a.p)(f.xV,["API/log/called"],void 0,n.K7.metrics,w),function(e,t,r={},i=y.p_.INFO){(0,a.p)(f.xV,["API/logging/".concat(i.toLowerCase(),"/called")],void 0,n.K7.metrics,e),(0,a.p)(y.ET,[(0,v.t)(),t,r,i],void 0,n.K7.logging,e)}(w,e,t,r)},m.wrapLogger=(e,t,{customAttributes:r={},level:i=y.p_.INFO}={})=>{(0,a.p)(f.xV,["API/wrapLogger/called"],void 0,n.K7.metrics,w),E(w,e,t,{customAttributes:r,level:i})},h.forEach((e=>{m[e]=j(A,e,!0,"api")})),m.addPageAction=j(A,"addPageAction",!0,n.K7.genericEvents),m.recordCustomEvent=j(A,"recordCustomEvent",!0,n.K7.genericEvents),m.setPageViewName=function(t,r){if("string"==typeof t)return"/"!==t.charAt(0)&&(t="/"+t),(0,o.f)(e).customTransaction=(r||"http://custom.transaction")+t,j(A,"setPageViewName",!0)()},m.setCustomAttribute=function(e,t,r=!1){if("string"==typeof e){if(["string","number","boolean"].includes(typeof t)||null===t)return N(e,t,"setCustomAttribute",r);(0,d.R)(40,typeof t)}else(0,d.R)(39,typeof e)},m.setUserId=function(e){if("string"==typeof e||null===e)return N("enduser.id",e,"setUserId",!0);(0,d.R)(41,typeof e)},m.setApplicationVersion=function(e){if("string"==typeof e||null===e)return N("application.version",e,"setApplicationVersion",!1);(0,d.R)(42,typeof e)},m.start=()=>{try{(0,a.p)(f.xV,["API/start/called"],void 0,n.K7.metrics,w),w.emit("manual-start-all")}catch(e){(0,d.R)(23,e)}},m[p.G4.RECORD]=function(){(0,a.p)(f.xV,["API/recordReplay/called"],void 0,n.K7.metrics,w),(0,a.p)(p.G4.RECORD,[],void 0,n.K7.sessionReplay,w)},m[p.G4.PAUSE]=function(){(0,a.p)(f.xV,["API/pauseReplay/called"],void 0,n.K7.metrics,w),(0,a.p)(p.G4.PAUSE,[],void 0,n.K7.sessionReplay,w)},m.interaction=function(e){return(new k).get("object"==typeof e?e:{})};const T=k.prototype={createTracer:function(e,t){var r={},i=this,o="function"==typeof t;return(0,a.p)(f.xV,["API/createTracer/called"],void 0,n.K7.metrics,w),g||(0,a.p)(_+"tracer",[(0,v.t)(),e,r],i,n.K7.spa,w),function(){if(R.emit((o?"":"no-")+"fn-start",[(0,v.t)(),i,o],r),o)try{return t.apply(this,arguments)}catch(e){const t="string"==typeof e?new Error(e):e;throw R.emit("fn-err",[arguments,this,t],r),t}finally{R.emit("fn-end",[(0,v.t)()],r)}}}};function j(e,t,r,i){return function(){return(0,a.p)(f.xV,["API/"+t+"/called"],void 0,n.K7.metrics,w),i&&(0,a.p)(e+t,[r?(0,v.t)():performance.now(),...arguments],r?null:this,i,w),r?void 0:this}}function I(){r.e(296).then(r.bind(r,778)).then((({setAPI:t})=>{t(e),(0,c.Ze)(e,"api")})).catch((e=>{(0,d.R)(27,e),w.abort()}))}return["actionText","setName","setAttribute","save","ignore","onEnd","getContext","end","get"].forEach((e=>{T[e]=j(_,e,void 0,g?n.K7.softNav:n.K7.spa)})),m.setCurrentRouteName=g?j(_,"routeName",void 0,n.K7.softNav):j(A,"routeName",!0,n.K7.spa),m.noticeError=function(t,r){"string"==typeof t&&(t=new Error(t)),(0,a.p)(f.xV,["API/noticeError/called"],void 0,n.K7.metrics,w),(0,a.p)("err",[t,(0,v.t)(),!1,r,!!x[e]],void 0,n.K7.jserrors,w)},l.RI?(0,u.GG)((()=>I()),!0):I(),m}var k=r(217),T=r(122);const j={accountID:void 0,trustKey:void 0,agentID:void 0,licenseKey:void 0,applicationID:void 0,xpid:void 0},I={};var O=r(284);const S=e=>{const t=e.startsWith("http");e+="/",r.p=t?e:"https://"+e};let P=!1;function K(e,t={},r,n){let{init:a,info:c,loader_config:u,runtime:d={},exposed:f=!0}=t;d.loaderType=r;const p=(0,g.pV)();c||(a=p.init,c=p.info,u=p.loader_config),(0,k.xN)(e.agentIdentifier,a||{}),function(e,t){if(!e)throw new Error("All loader-config objects require an agent identifier!");I[e]=(0,T.a)(t,j);const r=(0,g.nY)(e);r&&(r.loader_config=I[e])}(e.agentIdentifier,u||{}),c.jsAttributes??={},l.bv&&(c.jsAttributes.isWorker=!0),(0,i.x1)(e.agentIdentifier,c);const m=(0,k.D0)(e.agentIdentifier),h=[c.beacon,c.errorBeacon];P||(m.proxy.assets&&(S(m.proxy.assets),h.push(m.proxy.assets)),m.proxy.beacon&&h.push(m.proxy.beacon),_(),(0,g.US)("activatedFeatures",O.B),e.runSoftNavOverSpa&&=!0===m.soft_navigations.enabled&&m.feature_flags.includes("soft_nav")),d.denyList=[...m.ajax.deny_list||[],...m.ajax.block_internal?h:[]],d.ptid=e.agentIdentifier,(0,o.V)(e.agentIdentifier,d),e.ee=s.ee.get(e.agentIdentifier),void 0===e.api&&(e.api=N(e.agentIdentifier,n,e.runSoftNavOverSpa)),void 0===e.exposed&&(e.exposed=f),P=!0}},374:(e,t,r)=>{r.nc=(()=>{try{return document?.currentScript?.nonce}catch(e){}return""})()},860:(e,t,r)=>{"use strict";r.d(t,{$J:()=>u,K7:()=>s,P3:()=>c,XX:()=>i,qY:()=>n,v4:()=>a});const n="events",i="jserrors",o="browser/blobs",a="rum",s={ajax:"ajax",genericEvents:"generic_events",jserrors:i,logging:"logging",metrics:"metrics",pageAction:"page_action",pageViewEvent:"page_view_event",pageViewTiming:"page_view_timing",sessionReplay:"session_replay",sessionTrace:"session_trace",softNav:"soft_navigations",spa:"spa"},c={[s.pageViewEvent]:1,[s.pageViewTiming]:2,[s.metrics]:3,[s.jserrors]:4,[s.spa]:5,[s.ajax]:6,[s.sessionTrace]:7,[s.softNav]:8,[s.sessionReplay]:9,[s.logging]:10,[s.genericEvents]:11},u={[s.pageViewEvent]:a,[s.pageViewTiming]:n,[s.ajax]:n,[s.spa]:n,[s.softNav]:n,[s.metrics]:i,[s.jserrors]:i,[s.sessionTrace]:o,[s.sessionReplay]:o,[s.logging]:"browser/logs",[s.genericEvents]:"ins"}}},n={};function i(e){var t=n[e];if(void 0!==t)return t.exports;var o=n[e]={exports:{}};return r[e](o,o.exports,i),o.exports}i.m=r,i.d=(e,t)=>{for(var r in t)i.o(t,r)&&!i.o(e,r)&&Object.defineProperty(e,r,{enumerable:!0,get:t[r]})},i.f={},i.e=e=>Promise.all(Object.keys(i.f).reduce(((t,r)=>(i.f[r](e,t),t)),[])),i.u=e=>"nr-rum-1.283.2.min.js",i.o=(e,t)=>Object.prototype.hasOwnProperty.call(e,t),e={},t="NRBA-1.283.2.PROD:",i.l=(r,n,o,a)=>{if(e[r])e[r].push(n);else{var s,c;if(void 0!==o)for(var u=document.getElementsByTagName("script"),l=0;l<u.length;l++){var d=u[l];if(d.getAttribute("src")==r||d.getAttribute("data-webpack")==t+o){s=d;break}}if(!s){c=!0;var f={296:"sha512-2Y8GMAOGF658KnXzOZ/v+DlLch8TBFvV0tTNnOy9wrpvtDa1t5CdZMyX+LubTymBlzPp6NUjllBghMCZqXBPmg=="};(s=document.createElement("script")).charset="utf-8",s.timeout=120,i.nc&&s.setAttribute("nonce",i.nc),s.setAttribute("data-webpack",t+o),s.src=r,0!==s.src.indexOf(window.location.origin+"/")&&(s.crossOrigin="anonymous"),f[a]&&(s.integrity=f[a])}e[r]=[n];var g=(t,n)=>{s.onerror=s.onload=null,clearTimeout(p);var i=e[r];if(delete e[r],s.parentNode&&s.parentNode.removeChild(s),i&&i.forEach((e=>e(n))),t)return t(n)},p=setTimeout(g.bind(null,void 0,{type:"timeout",target:s}),12e4);s.onerror=g.bind(null,s.onerror),s.onload=g.bind(null,s.onload),c&&document.head.appendChild(s)}},i.r=e=>{"undefined"!=typeof Symbol&&Symbol.toStringTag&&Object.defineProperty(e,Symbol.toStringTag,{value:"Module"}),Object.defineProperty(e,"__esModule",{value:!0})},i.p="https://js-agent.newrelic.com/",(()=>{var e={374:0,840:0};i.f.j=(t,r)=>{var n=i.o(e,t)?e[t]:void 0;if(0!==n)if(n)r.push(n[2]);else{var o=new Promise(((r,i)=>n=e[t]=[r,i]));r.push(n[2]=o);var a=i.p+i.u(t),s=new Error;i.l(a,(r=>{if(i.o(e,t)&&(0!==(n=e[t])&&(e[t]=void 0),n)){var o=r&&("load"===r.type?"missing":r.type),a=r&&r.target&&r.target.src;s.message="Loading chunk "+t+" failed.\n("+o+": "+a+")",s.name="ChunkLoadError",s.type=o,s.request=a,n[1](s)}}),"chunk-"+t,t)}};var t=(t,r)=>{var n,o,[a,s,c]=r,u=0;if(a.some((t=>0!==e[t]))){for(n in s)i.o(s,n)&&(i.m[n]=s[n]);if(c)c(i)}for(t&&t(r);u<a.length;u++)o=a[u],i.o(e,o)&&e[o]&&e[o][0](),e[o]=0},r=self["webpackChunk:NRBA-1.283.2.PROD"]=self["webpackChunk:NRBA-1.283.2.PROD"]||[];r.forEach(t.bind(null,0)),r.push=t.bind(null,r.push.bind(r))})(),(()=>{"use strict";i(374);var e=i(944),t=i(344),r=i(566);class n{agentIdentifier;constructor(){this.agentIdentifier=(0,r.LA)(16)}#e(t,...r){if("function"==typeof this.api?.[t])return this.api[t](...r);(0,e.R)(35,t)}addPageAction(e,t){return this.#e("addPageAction",e,t)}recordCustomEvent(e,t){return this.#e("recordCustomEvent",e,t)}setPageViewName(e,t){return this.#e("setPageViewName",e,t)}setCustomAttribute(e,t,r){return this.#e("setCustomAttribute",e,t,r)}noticeError(e,t){return this.#e("noticeError",e,t)}setUserId(e){return this.#e("setUserId",e)}setApplicationVersion(e){return this.#e("setApplicationVersion",e)}setErrorHandler(e){return this.#e("setErrorHandler",e)}addRelease(e,t){return this.#e("addRelease",e,t)}log(e,t){return this.#e("log",e,t)}}class o extends n{#e(t,...r){if("function"==typeof this.api?.[t])return this.api[t](...r);(0,e.R)(35,t)}start(){return this.#e("start")}finished(e){return this.#e("finished",e)}recordReplay(){return this.#e(t.G4.RECORD)}pauseReplay(){return this.#e(t.G4.PAUSE)}addToTrace(e){return this.#e("addToTrace",e)}setCurrentRouteName(e){return this.#e("setCurrentRouteName",e)}interaction(){return this.#e("interaction")}wrapLogger(e,t,r){return this.#e("wrapLogger",e,t,r)}}var a=i(860),s=i(217);const c=Object.values(a.K7);function u(e){const t={};return c.forEach((r=>{t[r]=function(e,t){return!0===(0,s.gD)(t,"".concat(e,".enabled"))}(r,e)})),t}var l=i(603);var d=i(687),f=i(234),g=i(289),p=i(154),m=i(384);const h=e=>p.RI&&!0===(0,s.gD)(e,"privacy.cookies_enabled");function v(e){return!!(0,m.dV)().o.MO&&h(e)&&!0===(0,s.gD)(e,"session_trace.enabled")}var b=i(389);class y extends f.W{constructor(e,t,r=!0){super(e.agentIdentifier,t),this.auto=r,this.abortHandler=void 0,this.featAggregate=void 0,this.onAggregateImported=void 0,!1===e.init[this.featureName].autoStart&&(this.auto=!1),this.auto?(0,d.Ak)(e.agentIdentifier,t):this.ee.on("manual-start-all",(0,b.J)((()=>{(0,d.Ak)(e.agentIdentifier,this.featureName),this.auto=!0,this.importAggregator(e)})))}importAggregator(t,r={}){if(this.featAggregate||!this.auto)return;let n;this.onAggregateImported=new Promise((e=>{n=e}));const o=async()=>{let o;try{if(h(this.agentIdentifier)){const{setupAgentSession:e}=await i.e(296).then(i.bind(i,861));o=e(t)}}catch(t){(0,e.R)(20,t),this.ee.emit("internal-error",[t]),this.featureName===a.K7.sessionReplay&&this.abortHandler?.()}try{if(!this.#t(this.featureName,o))return(0,d.Ze)(this.agentIdentifier,this.featureName),void n(!1);const{lazyFeatureLoader:e}=await i.e(296).then(i.bind(i,103)),{Aggregate:a}=await e(this.featureName,"aggregate");this.featAggregate=new a(t,r),t.runtime.harvester.initializedAggregates.push(this.featAggregate),n(!0)}catch(t){(0,e.R)(34,t),this.abortHandler?.(),(0,d.Ze)(this.agentIdentifier,this.featureName,!0),n(!1),this.ee&&this.ee.abort()}};p.RI?(0,g.GG)((()=>o()),!0):o()}#t(e,t){switch(e){case a.K7.sessionReplay:return v(this.agentIdentifier)&&!!t;case a.K7.sessionTrace:return!!t;default:return!0}}}var w=i(630);class R extends y{static featureName=w.T;constructor(e,t=!0){super(e,w.T,t),this.importAggregator(e)}}var A=i(908),E=i(843),_=i(878),x=i(782),N=i(863);class k extends y{static featureName=x.T;constructor(e,t=!0){super(e,x.T,t),p.RI&&((0,E.u)((()=>(0,A.p)("docHidden",[(0,N.t)()],void 0,x.T,this.ee)),!0),(0,_.sp)("pagehide",(()=>(0,A.p)("winPagehide",[(0,N.t)()],void 0,x.T,this.ee))),this.importAggregator(e))}}var T=i(773);class j extends y{static featureName=T.TZ;constructor(e,t=!0){super(e,T.TZ,t),this.importAggregator(e)}}new class extends o{constructor(t){super(),p.gm?(this.features={},(0,m.bQ)(this.agentIdentifier,this),this.desiredFeatures=new Set(t.features||[]),this.desiredFeatures.add(R),this.runSoftNavOverSpa=[...this.desiredFeatures].some((e=>e.featureName===a.K7.softNav)),(0,l.j)(this,t,t.loaderType||"agent"),this.run()):(0,e.R)(21)}get config(){return{info:this.info,init:this.init,loader_config:this.loader_config,runtime:this.runtime}}run(){try{const t=u(this.agentIdentifier),r=[...this.desiredFeatures];r.sort(((e,t)=>a.P3[e.featureName]-a.P3[t.featureName])),r.forEach((r=>{if(!t[r.featureName]&&r.featureName!==a.K7.pageViewEvent)return;if(this.runSoftNavOverSpa&&r.featureName===a.K7.spa)return;if(!this.runSoftNavOverSpa&&r.featureName===a.K7.softNav)return;const n=function(e){switch(e){case a.K7.ajax:return[a.K7.jserrors];case a.K7.sessionTrace:return[a.K7.ajax,a.K7.pageViewEvent];case a.K7.sessionReplay:return[a.K7.sessionTrace];case a.K7.pageViewTiming:return[a.K7.pageViewEvent];default:return[]}}(r.featureName).filter((e=>!(e in this.features)));n.length>0&&(0,e.R)(36,{targetFeature:r.featureName,missingDependencies:n}),this.features[r.featureName]=new r(this)}))}catch(t){(0,e.R)(22,t);for(const e in this.features)this.features[e].abortHandler?.();const r=(0,m.Zm)();delete r.initializedAgents[this.agentIdentifier]?.api,delete r.initializedAgents[this.agentIdentifier]?.features,delete this.sharedAggregator;return r.ee.get(this.agentIdentifier).abort(),!1}}}({features:[R,k,j],loaderType:"lite"})})()})();</script>
<noscript><style>form.antibot * :not(.antibot-message) { display: none !important; }</style>
</noscript><script async src="https://www.googletagmanager.com/gtag/js?id=G-HEQ0YF2VYL"></script>
<script>window.dataLayer = window.dataLayer || [];function gtag(){dataLayer.push(arguments)};gtag("js", new Date());gtag("set", "developer_id.dMDhkMT", true);gtag('set', {'cookie_flags': 'SameSite=None;Secure', 'cookie_domain': 'www.nist.gov'});gtag("config", "G-HEQ0YF2VYL", {"groups":"default","page_placeholder":"PLACEHOLDER_page_location","link_attribution":true,"allow_ad_personalization_signals":false});gtag("config", "G-CSLL4ZEK4L", {"groups":"default","page_placeholder":"PLACEHOLDER_page_location","link_attribution":true,"allow_ad_personalization_signals":false});gtag("event", "custom", {"node_title":"Top NIST Images of 2018","node_id":"1539456","blog_author":"Robin Materese","content_type":"Blog entry"});</script>
<meta name="description" content="Theres nothing quite like a captivating image to make you want to learn more" />
<link rel="canonical" href="https://www.nist.gov/blogs/taking-measure/top-nist-images-2018" />
<link rel="shortlink" href="https://www.nist.gov/node/1539456" />
<meta name="citation_title" content="Top NIST Images of 2018 | NIST" />
<meta property="og:site_name" content="NIST" />
<meta property="og:type" content="Article" />
<meta property="og:url" content="https://www.nist.gov/blogs/taking-measure/top-nist-images-2018" />
<meta property="og:title" content="Top NIST Images of 2018" />
<meta property="og:description" content="Theres nothing quite like a captivating image to make you want to learn more" />
<meta property="og:image" content="https://www.nist.gov/sites/default/files/styles/social/public/images/2019/02/06/sim_kgs_closeup_2500px.png?itok=3xhPPpWU" />
<meta property="og:image" content="https://www.nist.gov/themes/custom/nist_www/img/homepage/nist_mark.png" />
<meta property="og:image:width" content="2400" />
<meta property="og:image:height" content="1548" />
<meta property="og:image:alt" content="stainless steel weights" />
<meta property="article:author" content="Robin Materese" />
<meta property="article:tag" content="bioscience" />
<meta property="article:published_time" content="2019-02-06T07:00-05:00" />
<meta property="article:modified_time" content="2025-02-25T15:19-05:00" />
<meta name="dcterms.title" content="Top NIST Images of 2018" />
<meta name="dcterms.creator" content="Robin Materese" />
<meta name="dcterms.description" content="Theres nothing quite like a captivating image to make you want to learn more" />
<meta name="dcterms.publisher" content="Robin Materese" />
<meta name="dcterms.contributor" content="NIST" />
<meta name="dcterms.date" content="2019-02-06T07:00-05:00" />
<meta name="dcterms.type" content="text" />
<meta name="dcterms.format" content="text/html" />
<meta name="dcterms.identifier" content="https://www.nist.gov/blogs/taking-measure/top-nist-images-2018" />
<meta name="dcterms.source" content="NIST" />
<meta name="dcterms.created" content="2019-02-06T07:00-05:00" />
<meta name="dcterms.modified" content="2025-02-25T15:19-05:00" />
<meta name="twitter:card" content="summary_large_image" />
<meta name="twitter:description" content="Theres nothing quite like a captivating image to make you want to learn more" />
<meta name="twitter:site" content="NIST" />
<meta name="twitter:title" content="Top NIST Images of 2018" />
<meta name="google-site-verification" content="QMu0ODkER3rN5hLcMLqNVf7e3bkjYsNLTuhqfH48jCA" />
<meta name="Generator" content="Drupal 10 (https://www.drupal.org)" />
<meta name="MobileOptimized" content="width" />
<meta name="HandheldFriendly" content="true" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<meta name="nist_search_modified" class="elastic" content="2025-02-25T15:19:00-05:00" />
<script type="application/ld+json">{
"@context": "https://schema.org",
"@graph": [
{
"@type": "Article",
"@id": "https://www.nist.gov/blogs/taking-measure/top-nist-images-2018",
"headline": "Top NIST Images of 2018",
"name": "Top NIST Images of 2018",
"description": "Theres nothing quite like a captivating image to make you want to learn more.",
"image": {
"@type": "ImageObject",
"url": "https://www.nist.gov/sites/default/files/styles/social/public/images/2019/02/06/sim_kgs_closeup_2500px.png?itok=3xhPPpWU",
"width": "2400",
"height": "1548"
},
"datePublished": "2019-02-06T07:00-05:00",
"dateModified": "2025-02-25T15:19-05:00",
"author": {
"@type": "Person",
"@id": "https://www.nist.gov/blogs/taking-measure/authors/robin-materese",
"name": "Robin Materese",
"url": "https://www.nist.gov/blogs/taking-measure/authors/robin-materese"
},
"publisher": {
"@type": "GovernmentOrganization",
"@id": "https://www.nist.gov/",
"name": "National Institute of Standards and Technology",
"url": "https://www.nist.gov/"
}
}
]
}</script>
<meta name="nist_search_bundle" class="elastic" content="blog" />
<link rel="icon" href="/themes/custom/nist_www/favicon.ico" type="image/vnd.microsoft.icon" />
<title>Top NIST Images of 2018 | NIST</title>
<link rel="stylesheet" media="all" href="/sites/default/files/css/css_ZtlGKjRlcsetYFZOgm4XEB79Us1_9Rfto8uYAe8uLYA.css?delta=0&amp;language=en&amp;theme=nist_www&amp;include=eJxNTgsOwyAIvZCpRzKorCNFaYTW9fazXZctIYT38j5ESEswGbP6-LsDJamuklqwJxYcnHCEFopkn0khMgamujg91LAMr-Kl9zNLBP54e-9fjC879T63bQWebuh2wq7-2tPI3vhOKTBXelByKomAQ8FMcLYMiuGQzcJ4I8mO7fBSMclfZaHURMnwDRYUV3Y" />
<link rel="stylesheet" media="all" href="/sites/default/files/css/css_kGS0ApDpFo-_3JI4Ijxg4RCWlTqsImK3lqH7bCv5v2U.css?delta=1&amp;language=en&amp;theme=nist_www&amp;include=eJxNTgsOwyAIvZCpRzKorCNFaYTW9fazXZctIYT38j5ESEswGbP6-LsDJamuklqwJxYcnHCEFopkn0khMgamujg91LAMr-Kl9zNLBP54e-9fjC879T63bQWebuh2wq7-2tPI3vhOKTBXelByKomAQ8FMcLYMiuGQzcJ4I8mO7fBSMclfZaHURMnwDRYUV3Y" />
<link rel="stylesheet" media="print" href="/sites/default/files/css/css_-IXwLuTUdm8IGHxib8GX8wWKw3LjKsNWSYYskZ5fEGg.css?delta=2&amp;language=en&amp;theme=nist_www&amp;include=eJxNTgsOwyAIvZCpRzKorCNFaYTW9fazXZctIYT38j5ESEswGbP6-LsDJamuklqwJxYcnHCEFopkn0khMgamujg91LAMr-Kl9zNLBP54e-9fjC879T63bQWebuh2wq7-2tPI3vhOKTBXelByKomAQ8FMcLYMiuGQzcJ4I8mO7fBSMclfZaHURMnwDRYUV3Y" />
<link rel="stylesheet" media="all" href="/sites/default/files/css/css_RS8YGnRq2Xi5aD-GQC3GKwBe6bOWBBmEmXrb2xB5FMM.css?delta=3&amp;language=en&amp;theme=nist_www&amp;include=eJxNTgsOwyAIvZCpRzKorCNFaYTW9fazXZctIYT38j5ESEswGbP6-LsDJamuklqwJxYcnHCEFopkn0khMgamujg91LAMr-Kl9zNLBP54e-9fjC879T63bQWebuh2wq7-2tPI3vhOKTBXelByKomAQ8FMcLYMiuGQzcJ4I8mO7fBSMclfZaHURMnwDRYUV3Y" />
<script src="/sites/default/files/js/js_GM8kl6wk698qKTTwusj83bCoGHHtOZ1UinjY1sE_Qbk.js?scope=header&amp;delta=0&amp;language=en&amp;theme=nist_www&amp;include=eJxdjdEOwiAMRX9o2E9qyqhYBboAE_17YW7RLOGBc3p7a2l-YNX-FrC_P97L5FV9YKRE4V1lLnAWU5JS8SrdOW0pKDmsuZdI8uDpOy5SWeKS9clwFuPK5uqNI_e7GixljOrASSHbi4Okx5YBH9RSMPsK3Jgc5wOxtfaX4Fcdi-DyulC47DjNGiOneugdjX2bp3Dj_G2O5JNcZZ6GLHhf44I9t8LGZrAZ_AFBzXxL"></script>
</head>
<body class="node-1539456">
<a href="#main-content" class="visually-hidden focusable" data-elastic-exclude>
Skip to main content
</a>
<div class="dialog-off-canvas-main-canvas" data-off-canvas-main-canvas>
<!-- nist-index-ignore-start -->
<section data-elastic-exclude class="usa-banner" aria-label="Official government website">
<div class="usa-accordion">
<header class="usa-banner__header">
<div class="usa-banner__inner">
<div class="grid-col-auto">
<img class="usa-banner__header-flag" src="/libraries/nist-component-library/dist/img/us_flag_small.png" alt="U.S. flag">
</div>
<div class="grid-col-fill tablet:grid-col-auto">
<p class="usa-banner__header-text">An official website of the United States government</p>
<p class="usa-banner__header-action" aria-hidden="true">Heres how you know</p>
</div>
<button class="usa-accordion__button usa-banner__button" aria-expanded="false" aria-controls="gov-banner-default">
<span class="usa-banner__button-text">Heres how you know</span>
</button>
</div>
</header>
<div class="usa-banner__content usa-accordion__content" id="gov-banner-default">
<div class="grid-row grid-gap-lg">
<div class="usa-banner__guidance tablet:grid-col-6">
<img class="usa-banner__icon usa-media-block__img" src="/libraries/nist-component-library/dist/img/icon-dot-gov.svg" role="img" alt="" aria-hidden="true">
<div class="usa-media-block__body">
<p>
<strong>Official websites use .gov</strong>
<br/>
A <strong>.gov</strong> website belongs to an official government organization in the United States.
</p>
</div>
</div>
<div class="usa-banner__guidance tablet:grid-col-6">
<img class="usa-banner__icon usa-media-block__img" src="/libraries/nist-component-library/dist/img/icon-https.svg" role="img" alt="" aria-hidden="true">
<div class="usa-media-block__body">
<p>
<strong>Secure .gov websites use HTTPS</strong>
<br/>
A <strong>lock</strong> ( <span class="icon-lock">
<svg xmlns="http://www.w3.org/2000/svg" width="52" height="64" viewbox="0 0 52 64" class="usa-banner__lock-image" role="img" aria-labelledby="banner-lock-title banner-lock-description" focusable="false">
<title id="banner-lock-title">Lock</title>
<desc id="banner-lock-description">A locked padlock</desc><path fill="#000000" fill-rule="evenodd" d="M26 0c10.493 0 19 8.507 19 19v9h3a4 4 0 0 1 4 4v28a4 4 0 0 1-4 4H4a4 4 0 0 1-4-4V32a4 4 0 0 1 4-4h3v-9C7 8.507 15.507 0 26 0zm0 8c-5.979 0-10.843 4.77-10.996 10.712L15 19v9h22v-9c0-6.075-4.925-11-11-11z"/></svg>
</span>
) or <strong>https://</strong> means youve safely connected to the .gov website. Share sensitive information only on official, secure websites.
</p>
</div>
</div>
</div>
</div>
</div>
</section>
<!-- nist-index-ignore-end -->
<div data-elastic-exclude>
<!-- nist-index-ignore-start -->
<div class="nist-print-header" style="display:none;">
<p class="nist-print-header__url">https://www.nist.gov/blogs/taking-measure/top-nist-images-2018</p>
<img class="nist-print-header__logo" width="289" height="38" src="/libraries/nist-component-library/dist/img/logo/nist_logo_sidestack.svg" alt="National Institute of Standards and Technology" />
</div>
<div class="usa-overlay"></div>
<header class="usa-header nist-header--www nist-header--minimal" role="banner">
<div class="usa-navbar">
<div class="usa-logo flex-fill">
<a href="/" title="National Institute of Standards and Technology" aria-label="Home">
<img src="/libraries/nist-component-library/dist/img/logo/logo.svg" alt="National Institute of Standards and Technology" width="300px" height="80px" />
</a>
</div>
<div class="usa-header__right grid-row flex-auto">
<div class="grid-col-fill nist-header__search-group">
<form class="usa-search usa-search--small"
accept-charset="UTF-8"
action="/search"
id="search_form"
method="get">
<div role="search">
<label class="usa-sr-only" for="search-form">Search NIST</label>
<input class="usa-input" id="search-form" type="search" name="s" placeholder="Search NIST" required="" maxlength="128">
<button class="usa-button" type="submit"><img src="/libraries/nist-component-library/dist/img/usa-icons-bg/search--white.svg" class="usa-search__submit-icon" alt="Search"></button>
</div>
</form>
</div>
<div class="grid-col-auto padding-left-1">
<button class="usa-menu-btn">Menu</button>
</div>
</div>
</div>
<nav aria-label="Primary navigation" class="usa-nav">
<div class="usa-nav__inner">
<button class="usa-nav__close">Close</button>
<ul class="usa-nav__primary usa-accordion">
<li class="usa-nav__primary-item">
<a class="usa-nav__link" href="/publications">Publications</a>
</li>
<li class="usa-nav__primary-item">
<button class="usa-accordion__button usa-nav__link" aria-expanded="false" aria-controls="primary_menu-2"><span>What We Do</span></button>
<div id="primary_menu-2" class="usa-nav__submenu usa-megamenu">
<div class="grid-row">
<div class="tablet:grid-col-fill"><ul class="usa-nav__submenu-list">
<li class="usa-nav__submenu-item">
<a href="/topics" class="usa-nav__link">All Topics</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/advanced-communications" class="usa-nav__link">Advanced communications</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/artificial-intelligence" class="usa-nav__link">Artificial intelligence</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/bioscience" class="usa-nav__link">Bioscience</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/buildings-construction" class="usa-nav__link">Buildings and construction</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/chemistry" class="usa-nav__link">Chemistry</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/cybersecurity" class="usa-nav__link">Cybersecurity</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/electronics" class="usa-nav__link">Electronics</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/energy" class="usa-nav__link">Energy</a>
</li>
</ul></div><div class="column-break tablet:grid-col-fill"><ul class="usa-nav__submenu-list">
<li class="usa-nav__submenu-item">
<a href="/environment" class="usa-nav__link">Environment</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/fire" class="usa-nav__link">Fire</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/forensic-science" class="usa-nav__link">Forensic science</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/health" class="usa-nav__link">Health</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/information-technology" class="usa-nav__link">Information technology</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/infrastructure" class="usa-nav__link">Infrastructure</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/manufacturing" class="usa-nav__link">Manufacturing</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/materials" class="usa-nav__link">Materials</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/mathematics-statistics" class="usa-nav__link">Mathematics and statistics</a>
</li>
</ul></div><div class="column-break tablet:grid-col-fill"><ul class="usa-nav__submenu-list">
<li class="usa-nav__submenu-item">
<a href="/metrology" class="usa-nav__link">Metrology</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/nanotechnology" class="usa-nav__link">Nanotechnology</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/neutron-research" class="usa-nav__link">Neutron research</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/performance-excellence" class="usa-nav__link">Performance excellence</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/physics" class="usa-nav__link">Physics</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/public-safety" class="usa-nav__link">Public safety</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/quantum-information-science" class="usa-nav__link">Quantum information science</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/resilience" class="usa-nav__link">Resilience</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/standards" class="usa-nav__link">Standards</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/transportation" class="usa-nav__link">Transportation</a>
</li>
</ul>
</div>
</div>
</div>
</li>
<li class="usa-nav__primary-item">
<button class="usa-accordion__button usa-nav__link" aria-expanded="false" aria-controls="primary_menu-3"><span>Labs &amp; Major Programs</span></button>
<div id="primary_menu-3" class="usa-nav__submenu usa-megamenu">
<div class="grid-row">
<div class="tablet:grid-col-fill"><ul class="usa-nav__submenu-list">
<li class="usa-nav__submenu-item">
<a href="/adlp" class="usa-nav__link">Assoc Director of Laboratory Programs</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/laboratories" class="usa-nav__link">Laboratories</a>
<ul class="usa-nav__submenu-list">
<li>
<a href="/ctl" class="usa-nav__link">Communications Technology Laboratory</a>
</li>
<li>
<a href="/el" class="usa-nav__link">Engineering Laboratory</a>
</li>
<li>
<a href="/itl" class="usa-nav__link">Information Technology Laboratory</a>
</li>
<li>
<a href="/mml" class="usa-nav__link">Material Measurement Laboratory</a>
</li>
<li>
<a href="/pml" class="usa-nav__link">Physical Measurement Laboratory</a>
</li>
</ul>
</li>
</ul></div><div class="column-break tablet:grid-col-fill"><ul class="usa-nav__submenu-list">
<li class="usa-nav__submenu-item">
<a href="/user-facilities" class="usa-nav__link">User Facilities</a>
<ul class="usa-nav__submenu-list">
<li>
<a href="/ncnr" class="usa-nav__link">NIST Center for Neutron Research</a>
</li>
<li>
<a href="/cnst" class="usa-nav__link">CNST NanoFab</a>
</li>
</ul>
</li>
<li class="usa-nav__submenu-item">
<a href="/labs-major-programs/research-test-beds" class="usa-nav__link">Research Test Beds</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/laboratories/projects-programs" class="usa-nav__link">Research Projects</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/laboratories/tools-instruments" class="usa-nav__link">Tools &amp; Instruments</a>
</li>
</ul></div><div class="column-break tablet:grid-col-fill"><ul class="usa-nav__submenu-list">
<li class="usa-nav__submenu-item">
<a href="/major-programs" class="usa-nav__link">Major Programs</a>
<ul class="usa-nav__submenu-list">
<li>
<a href="/baldrige" class="usa-nav__link">Baldrige Performance Excellence Program</a>
</li>
<li>
<a href="/chips" class="usa-nav__link">CHIPS for America Initiative</a>
</li>
<li>
<a href="/mep" class="usa-nav__link">Manufacturing Extension Partnership (MEP)</a>
</li>
<li>
<a href="/oam" class="usa-nav__link">Office of Advanced Manufacturing</a>
</li>
<li>
<a href="/spo" class="usa-nav__link">Special Programs Office</a>
</li>
<li>
<a href="/tpo" class="usa-nav__link">Technology Partnerships Office</a>
</li>
</ul>
</li>
</ul>
</div>
</div>
</div>
</li>
<li class="usa-nav__primary-item">
<button class="usa-accordion__button usa-nav__link" aria-expanded="false" aria-controls="primary_menu-4"><span>Services &amp; Resources</span></button>
<div id="primary_menu-4" class="usa-nav__submenu usa-megamenu">
<div class="grid-row">
<div class="tablet:grid-col-fill"><ul class="usa-nav__submenu-list">
<li class="usa-nav__submenu-item">
<a href="/content/standards-measurements" class="usa-nav__link">Standards and Measurements</a>
<ul class="usa-nav__submenu-list">
<li>
<a href="/calibrations" class="usa-nav__link">Calibration Services</a>
</li>
<li>
<a href="/nvlap" class="usa-nav__link">Laboratory Accreditation (NVLAP)</a>
</li>
<li>
<a href="/nist-quality-system" class="usa-nav__link">Quality System</a>
</li>
<li>
<a href="/srm" class="usa-nav__link">Standard Reference Materials (SRMs)</a>
</li>
<li>
<a href="/sri" class="usa-nav__link">Standard Reference Instruments (SRIs)</a>
</li>
<li>
<a href="/standardsgov" class="usa-nav__link">Standards.gov</a>
</li>
<li>
<a href="/pml/time-and-frequency-division/time-services" class="usa-nav__link">Time Services</a>
</li>
<li>
<a href="/pml/owm" class="usa-nav__link">Office of Weights and Measures</a>
</li>
</ul>
</li>
</ul></div><div class="column-break tablet:grid-col-fill"><ul class="usa-nav__submenu-list">
<li class="usa-nav__submenu-item">
<a href="/services-resources/software" class="usa-nav__link">Software</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/data" class="usa-nav__link">Data</a>
<ul class="usa-nav__submenu-list">
<li>
<a href="https://webbook.nist.gov/chemistry/" class="usa-nav__link">Chemistry WebBook</a>
</li>
<li>
<a href="https://nvd.nist.gov/" class="usa-nav__link">National Vulnerability Database</a>
</li>
<li>
<a href="/pml/productsservices/physical-reference-data" class="usa-nav__link">Physical Reference Data</a>
</li>
<li>
<a href="/srd" class="usa-nav__link">Standard Reference Data (SRD)</a>
</li>
</ul>
</li>
<li class="usa-nav__submenu-item">
<a href="https://shop.nist.gov/" class="usa-nav__link">Storefront</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/tpo" class="usa-nav__link">License &amp; Patents</a>
</li>
</ul></div><div class="column-break tablet:grid-col-fill"><ul class="usa-nav__submenu-list">
<li class="usa-nav__submenu-item">
<a href="https://csrc.nist.gov/" class="usa-nav__link">Computer Security Resource Center (CSRC)</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/nist-research-library" class="usa-nav__link">NIST Research Library</a>
</li>
</ul>
</div>
</div>
</div>
</li>
<li class="usa-nav__primary-item">
<button class="usa-accordion__button usa-nav__link" aria-expanded="false" aria-controls="primary_menu-5"><span>News &amp; Events</span></button>
<div id="primary_menu-5" class="usa-nav__submenu usa-megamenu">
<div class="grid-row">
<div class="tablet:grid-col-fill"><ul class="usa-nav__submenu-list">
<li class="usa-nav__submenu-item">
<a href="/news-events/news" class="usa-nav__link">News</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/news-events/events" class="usa-nav__link">Events</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/blogs" class="usa-nav__link">Blogs</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/feature-stories" class="usa-nav__link">Feature Stories</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/awards" class="usa-nav__link">Awards</a>
</li>
</ul></div><div class="column-break tablet:grid-col-fill"><ul class="usa-nav__submenu-list">
<li class="usa-nav__submenu-item">
<a href="/video-gallery" class="usa-nav__link">Video Gallery</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/image-gallery" class="usa-nav__link">Image Gallery</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/pao/media-contacts" class="usa-nav__link">Media Contacts</a>
</li>
</ul>
</div>
</div>
</div>
</li>
<li class="usa-nav__primary-item">
<button class="usa-accordion__button usa-nav__link" aria-expanded="false" aria-controls="primary_menu-6"><span>About NIST</span></button>
<div id="primary_menu-6" class="usa-nav__submenu usa-megamenu">
<div class="grid-row">
<div class="tablet:grid-col-fill"><ul class="usa-nav__submenu-list">
<li class="usa-nav__submenu-item">
<a href="/about-nist" class="usa-nav__link">About Us</a>
<ul class="usa-nav__submenu-list">
<li>
<a href="/director/leadership" class="usa-nav__link">Leadership</a>
</li>
<li>
<a href="/director/nist-organization-structure" class="usa-nav__link">Organization Structure</a>
</li>
<li>
<a href="/about-nist/budget-planning" class="usa-nav__link">Budget &amp; Planning</a>
</li>
</ul>
</li>
<li class="usa-nav__submenu-item">
<a href="/about-nist/contact-us" class="usa-nav__link">Contact Us</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/about-nist/visit" class="usa-nav__link">Visit</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/careers" class="usa-nav__link">Careers</a>
<ul class="usa-nav__submenu-list">
<li>
<a href="/iaao/academic-affairs-office" class="usa-nav__link">Student programs</a>
</li>
</ul>
</li>
</ul></div><div class="column-break tablet:grid-col-fill"><ul class="usa-nav__submenu-list">
<li class="usa-nav__submenu-item">
<a href="/about-nist/work-nist" class="usa-nav__link">Work with NIST</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/history" class="usa-nav__link">History</a>
<ul class="usa-nav__submenu-list">
<li>
<a href="http://nistdigitalarchives.contentdm.oclc.org/" class="usa-nav__link">NIST Digital Archives</a>
</li>
<li>
<a href="/nist-museum" class="usa-nav__link">NIST Museum</a>
</li>
<li>
<a href="/nist-and-nobel" class="usa-nav__link">NIST and the Nobel</a>
</li>
</ul>
</li>
<li class="usa-nav__submenu-item">
<a href="/education" class="usa-nav__link">Educational Resources</a>
</li>
</ul>
</div>
</div>
</div>
</li>
</ul>
</div>
</nav>
</header>
<!-- nist-index-ignore-end -->
</div>
<div class="grid-container">
</div>
<div
id="block-nist-www-content" class="nist-block"
>
<section
class="nist-page__content usa-section clearfix"
>
<a id="main-content" tabindex="-1"></a>
<div
class="nist-page__region nist-page__region--content-top-full"
>
<div
class="nist-block"
>
<div class="entity-reference">
<div class="nist-blog-header nist-blog-header--purple nist-blog-header--inner">
<div class="nist-blog-header__bkgrd">
<div class="nist-blog-header__main grid-container">
<div class="grid-row">
<h2 class="nist-blog-header__title">
<a href="/blogs/taking-measure"> Taking Measure
</a>
</h2>
<div class="nist-blog-header__tagline">
<p class="text">Just a Standard Blog</p>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
<div class="grid-container margin-top-4">
<div
class="nist-page__region nist-page__region--content-top"
>
<div
class="nist-block"
>
<h1 class="nist-page__title">Top NIST Images of 2018</h1>
</div>
<div
class="font-body-md"
>
<div class="daterange"><time datetime="2019-02-06T12:00:00Z">February 6, 2019</time>
</div>
</div>
<div
class="nist-block"
>
<span>By: </span>
<a href="/blogs/taking-measure/authors/robin-materese" hreflang="en">Robin Materese</a>
</div>
<div
class="nist-block"
>
<!-- nist-index-ignore-start -->
<div data-elastic-exclude class="nist-block nist-social__wrapper">
<h2 class="nist-social__title">Share</h2>
<div class="social-media-sharing">
<div class="nist-social__wrapper--share">
<div>
<a target="_blank" rel="noopener" href="https://www.facebook.com/share.php?u=https://www.nist.gov/blogs/taking-measure/top-nist-images-2018"
title="Facebook" class="nist-social nist-social--facebook-gray">
<span>Facebook</span>
</a>
</div>
<div>
<a target="_blank" rel="noopener" href="https://www.linkedin.com/shareArticle?mini=true&amp;url=https://www.nist.gov/blogs/taking-measure/top-nist-images-2018&amp;source=https://www.nist.gov/blogs/taking-measure/top-nist-images-2018"
title="Linkedin" class="nist-social nist-social--linkedin-gray">
<span>Linkedin</span>
</a>
</div>
<div>
<a target="_blank" rel="noopener" href="https://x.com/intent/tweet?url=https://www.nist.gov/blogs/taking-measure/top-nist-images-2018&amp;status=https://www.nist.gov/blogs/taking-measure/top-nist-images-2018"
title="X.com" class="nist-social nist-social--x-gray">
<span>X.com</span>
</a>
</div>
<div>
<a href="mailto:?subject=NIST.gov&amp;body=Check out this site https://www.nist.gov/blogs/taking-measure/top-nist-images-2018"
title="Email" class="nist-social nist-social--envelope-gray">
<span>Email</span>
</a>
</div>
</div>
</div>
</div>
<!-- nist-index-ignore-end -->
</div>
</div>
</div>
<div class="grid-container margin-top-4">
<div class="grid-row grid-gap-6">
<div
class="nist-page__region nist-page__region--content tablet-lg:grid-col-8"
>
<div
class="nist-block"
>
<div class="text-with-summary">
<figure class="nist-image--lightbox nist-image" data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2019/02/06/sim_kgs_closeup_2500px.png?itok=acK6V91q" data-media-id="469946">
<img loading="lazy" src="/sites/default/files/styles/960_x_960_limit/public/images/2019/02/06/sim_kgs_closeup_2500px.png?itok=PkgDAxTb" width="960" height="619" alt="stainless steel weights" typeof="foaf:Image" />
<figcaption class="nist-image__caption">
<div data-caption-editable="true" class="nist-image__caption-content">
<p>A selection of the 1-kg stainless steel weights used in a study to determine why precision mass standards that are supposed to be identical drift over time. Such drift was one of the reasons behind the redefinition of the kilogram in terms of unvarying constants of nature in November 2018.</p>
</div>
<div class="nist-image__credit">
<span class="nist-image__credit-label">Credit:</span>
Jennifer Lauren Lee/NIST
</div>
</figcaption>
</figure>
<p>Theres nothing quite like a captivating image to make you want to learn more. And nowhere is that more apparent than when it comes to sometimes hard-to-understand science. Before we all get too settled into 2019, we thought wed take a look back at some of our best pictures from 2018. If you missed these images the first time we shared them — on our website or in social media — we hope youll take the time this go-round to learn a little bit more about what we do.</p><p>AUTHORs NOTE: These images were all shared by NIST for the first time in 2018. Some may have been taken prior to that year. Images are listed below in no particular order.</p><h2>NIST in space</h2><p>&nbsp;</p>
<div class="align-center nist-image--lightbox nist-image" data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2019/02/06/cnt_chip_2018.jpg?itok=Ii5y-MUJ" data-media-id="483001">
<img loading="lazy" src="/sites/default/files/images/2019/02/06/cnt_chip_2018.jpg" width="4592" height="3448" alt="a close up of a portion of a long rectangular chip resting on a quarter." typeof="foaf:Image">
<div class="nist-image__credit">
<span class="nist-image__credit-label">Credit:</span>
NIST
</div>
</div>
<p>This novel “NIST on a chip” instrument was launched into space on a satellite from Vandenburg Air Force Base in California on Monday, December 3, 2018. (Weve placed it on top of a quarter so you can get a sense of just how small this device is!) The chip is part of the <a href="/measuring-cosmos/compact-spectral-irradiance-monitor" data-entity-type="node" data-entity-uuid="0ac975d2-d787-4d32-be36-c4909ce473b5" data-entity-substitution="canonical" title="Compact Spectral Irradiance Monitor">Compact Spectral Irradiance Monitor (CSIM)</a>, an instrument that will monitor and measure the suns radiation for two years to help researchers understand how solar variability affects Earths climate. (The mission also is testing the effectiveness of smaller satellites that orbit for shorter lengths of time. The data from CSIM will be compared to data from a larger satellite.) The chips, which consist of carbon nanotubes and metals patterned on silicon wafers, measure light intensity and are smaller, faster, cheaper and equally, if not more, accurate than their predecessors. The chips were made under a recent agreement between NIST and the University of Colorado Boulder's Laboratory for Atmospheric and Space Physics (LASP), which built the CSIM.</p><h2>Sweet tats!</h2><p>&nbsp;</p>
<div class="align-center nist-image--lightbox nist-image" data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2019/03/19/schlamminger_seifert_haddad_chao_pratt_newell_kg_tats.jpg?itok=JCP2Jlgj" data-media-id="483056">
<img loading="lazy" src="/sites/default/files/images/2019/03/19/schlamminger_seifert_haddad_chao_pratt_newell_kg_tats.jpg" width="3000" height="2000" alt="NIST researchers wearing hairnets proudly and happily present their forearms bearing tattoos of the value of the Planck constant" typeof="foaf:Image">
<div class="nist-image__credit">
<span class="nist-image__credit-label">Credit:</span>
J. Stoughton/NIST
</div>
</div>
<p>Three are permanent. Three are henna. All mark the 2018 redefinition of the kilogram. Starting in May 2019, the kilogram will no longer be based on an artifact kept in a vault in France. Instead, it will be based on a new agreed upon value for the Planck Constant. The vote was the culmination of a years-long international scientific quest for even greater precision. As to the real impact of this change … well, thats an unknown at this point; however, historically, increasing the precision of a measurement or unit has resulted in some pretty amazing technological advances. (Think GPS, for one.) Find out more about the initiative and the science on our <a href="https://www.nist.gov/si-redefinition">SI Redefinition microsite</a></p><h2>DNA barcodes?</h2><p>&nbsp;</p>
<div class="align-center nist-image--lightbox nist-image" data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2018/04/26/18mml011_dna-barcode-illustration-horizontal-2mb.jpg?itok=77DTm2j3" data-media-id="449471">
<img loading="lazy" src="/sites/default/files/images/2018/04/26/18mml011_dna-barcode-illustration-horizontal-2mb.jpg" width="2000" height="1326" alt="Artwork shows a hand with tweezers inserting a piece of DNA in a larger strand. The smaller piece has a black and white barcode attached." title="DNA Barcode Ilustration" typeof="foaf:Image">
<div class="nist-image__credit">
<span class="nist-image__credit-label">Credit:</span>
Kelly Irvine/NIST
</div>
</div>
<p>Ever since the human genome was declared officially sequenced in 2003, scientist, doctors and the general public have been excited about what it could mean for medicine. At the center of the excitement is CRISPR, a genome-editing technique that shows great potential for allowing doctors to “clip out” disease-causing genetic mutations. Last spring, researchers at the Joint Initiative for Metrology in Biology (JIMB, a collaboration between Stanford University and NIST) developed a new CRISPR platform called MAGESTIC. In the words of NIST science writer Alison Gillespie, “… the new platform makes CRISPR less like a blunt cutting tool and more like a word processor by enabling an efficient search and replace function for genetic material.” <a href="https://www.nist.gov/news-events/news/2018/05/clipping-scissors-word-processor">Read more about MAGESTIC</a></p><h2>Science for the ages</h2><p>&nbsp;</p>
<div class="align-center nist-image--lightbox nist-image" data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2018/01/11/nist_stone_wall.jpg?itok=VHgRbV1C" data-media-id="418111">
<img loading="lazy" src="/sites/default/files/images/2018/01/11/nist_stone_wall.jpg" width="2700" height="1688" alt="NIST stone wall weathering experiment" typeof="foaf:Image">
<div class="nist-image__credit">
<span class="nist-image__credit-label">Credit:</span>
J. Stoughton/NIST
</div>
</div>
<p>What may look like just a cool patterned wall actually comes with some serious science! Made up of more than 2,000 square and rectangular stone samples from all over the world, the 70-year-old wall is the longest-running weathering experiment of its kind. The wall started out on NISTs Washington, D.C., campus and was moved to its Gaithersburg, Maryland, home when the organization headed to the suburbs in the 1960s. Learn more about the wall in this <a href="https://www.nist.gov/blogs/taking-measure/test-time-nists-wall-many-stones">blog post</a>.</p><h2>Its getting cold up in here!</h2><p>&nbsp;</p>
<div class="align-center nist-image--lightbox nist-image" data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2018/07/17/18mml022_preparing-a-sample-at-hml-alex-holt-032.jpg?itok=qsTCJLib" data-media-id="458246">
<img loading="lazy" src="/sites/default/files/images/2018/07/17/18mml022_preparing-a-sample-at-hml-alex-holt-032.jpg" width="3000" height="2000" alt="Giant metal tubs are being opened and white vapor is puffing up into the face of one researcher who is in a protective suit with hood, gloves and eye protection. In the background, several other suited researchers discuss something." typeof="foaf:Image">
<div class="nist-image__credit">
<span class="nist-image__credit-label">Credit:</span>
A. Holt/NIST
</div>
</div>
<p>Ah, liquid nitrogen. Known around high school science classrooms as that smoky substance that helps teachers grab their students attention, it actually serves important purposes in scientific research and sample preservation. For NIST, it helps preserve the hundreds of specimens stored in the labs environmental specimen bank. The specimens include tissue from marine mammals, sea turtles, mussels and oysters, as well as eggs from seabirds and peregrine falcons. Oh, and theres also human liver tissue from EPA studies, too. The items stored here are incredibly rare and, in some cases, irreplaceable, so its critical that they be preserved … even when their home in Charleston, South Carolina, is under attack from Mother Nature. Learn more about NISTs environmental specimen bank and how the scientists there prepare for bad weather in this <a href="https://www.nist.gov/featured-stories/staying-chill-even-when-disaster-strikes">feature story</a></p><h2>It's a trap!</h2><p>&nbsp;</p>
<div class="align-center nist-image--lightbox nist-image" data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2019/02/06/neutron_lifetime_proton_trap.jpg?itok=1p0n2a95" data-media-id="483066">
<img loading="lazy" src="/sites/default/files/images/2019/02/06/neutron_lifetime_proton_trap.jpg" width="5937" height="3963" alt="cylindrical rod of metal-banded disks capped by aluminum donuts resting on a metal table. A band of blue circuitry runs along the top. " typeof="foaf:Image">
<div class="nist-image__credit">
<span class="nist-image__credit-label">Credit:</span>
F. Webber/NIST
</div>
</div>
<p>But dont worry, youre not likely to get caught in it. Researchers at the NIST Center for Neutron Research are using this proton trap to measure the neutrons lifespan, or the amount of time it takes for a neutron to decay into its component parts (a proton, an electron and an electron antineutrino). Scientists shoot a beam of neutrons into the proton trap. As the neutrons decay, the protons are caught and counted. From the number of trapped protons, the neutron lifetime can be calculated. This device is at the center of a current scientific debate: Is the neutron lifetime 14 minutes and 39 seconds or 14 minutes and 48 seconds? Those 9 seconds may not seem like much, but they could hold the key to discovering the origin and identity of dark matter. While the verdict is still out on what dark matter is or which count is correct, we do know that precisely measuring the neutron lifetime will give us a better understanding of fundamental physics, the Big Bang and our future.</p><h2>Math as art?</h2><h3>&nbsp;</h3>
<div class="align-center nist-image--lightbox nist-image" data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2019/02/06/sine-cosine_art.jpg?itok=eeP8Q9_x" data-media-id="483071">
<img loading="lazy" src="/sites/default/files/images/2019/02/06/sine-cosine_art.jpg" width="1320" height="1320" alt="a graphic representation of sine-cosine equations in red" typeof="foaf:Image">
<div class="nist-image__credit">
<span class="nist-image__credit-label">Credit:</span>
H. Iyer/NIST
</div>
</div>
<p>Now, this is a TRUE example of STEAM (Science-Technology-Engineering-Art-Mathematics)! Created by NIST mathematician Hari Iyer, this computer-generated art is the result of tracing out undulating mathematical functions known as sines and cosines. But Haris work isnt just about making something pretty. Mathematicians can combine sines and cosines to help model actual surfaces that can then be used to engineer shapes for objects such as car parts. Not that youll be seeing this particular sine-cosine pattern resulting in a car part any time soon!*</p><h2>Geometry and trigonometry and astronomy, oh my!</h2><p>&nbsp;</p>
<div class="align-center nist-image--lightbox nist-image" data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2019/02/06/quantum-sensors-atacama_telescope.jpg?itok=uxdY5x7J" data-media-id="483076">
<img loading="lazy" src="/sites/default/files/images/2019/02/06/quantum-sensors-atacama_telescope.jpg" width="1080" height="1350" alt="close up of a gold-hued sensor chip patterned with rhombuses with circles and crosses inscribed within them " typeof="foaf:Image">
<div class="nist-image__credit">
<span class="nist-image__credit-label">Credit:</span>
D. Schmidt/NIST
</div>
</div>
<p>NIST researchers used geometry and trigonometry to create these rhomboidal (flattened square) tiles to make up hexagonal detector chips for the <a href="https://act.princeton.edu/">Atacama Cosmology Telescope</a> in Chile. These tiles are unique because most integrated circuits are made with tools that use all right angles, meaning the resulting tiles are squares. Why does this matter? Because hexagons collect about 20 percent more data. That means these tiles will make the scope's camera about 20 percent more efficient at collecting light and help it get a better picture of the early universe. (NOTE: While the small tiles are rhombuses or parallelograms, they make it possible for the entire chip to have a hexagon shape.)</p><p>*<em>For those interested in the mathematical details, the pattern was created by using the following equations: first closed curve: [x(t) = (sin(11pit))<sup>3</sup>, y(t) = (cos(33pit))<sup>3</sup>]; second closed curve: [x(t) = (2/3)(sin(30pit))<sup>3</sup>, y(t) = (2/3)(cos(10pit))<sup>3</sup>]</em></p>
</div>
</div>
<div
class="nist-block"
>
<div class="nist-tags">
<a href="/blogs/taking-measure/categories/248321">Bioscience</a>,
<a href="/blogs/taking-measure/categories/2813426">Genome editing</a>,
<a href="/blogs/taking-measure/categories/248346">Genomics</a>,
<a href="/blogs/taking-measure/categories/248371">Buildings and Construction</a>,
<a href="/blogs/taking-measure/categories/248486">Electronics</a>,
<a href="/blogs/taking-measure/categories/248516">Sensors</a>,
<a href="/blogs/taking-measure/categories/248561">Environment</a>,
<a href="/blogs/taking-measure/categories/248581">Marine science</a>,
<a href="/blogs/taking-measure/categories/248946">Materials</a>,
<a href="/blogs/taking-measure/categories/248961">Concrete / cement</a>,
<a href="/blogs/taking-measure/categories/248966">Materials characterization</a>,
<a href="/blogs/taking-measure/categories/249011">Mathematics and statistics</a>,
<a href="/blogs/taking-measure/categories/249031">Modeling and simulation research</a>,
<a href="/blogs/taking-measure/categories/249051">Metrology</a>,
<a href="/blogs/taking-measure/categories/249101">Mass metrology</a>,
<a href="/blogs/taking-measure/categories/2746606">Metric</a>,
<a href="/blogs/taking-measure/categories/249451">Neutron research</a>,
<a href="/blogs/taking-measure/categories/249241">Physics</a> and
<a href="/blogs/taking-measure/categories/249271">Nuclear physics</a></div>
</div>
<div
class="nist-block"
>
<h2
class="nist-block__title"
>About the author</h2>
<div class="nist-field nist-field--label-hidden entity-reference">
<div class="nist-field__items">
<div class="nist-field__item">
<article
about="/blogs/taking-measure/authors/robin-materese" class="nist-teaser"
>
<div class="nist-teaser__image">
<div class="entity-reference"> <a href="/blogs/taking-measure/authors/robin-materese" hreflang="en"><img loading="lazy" src="/sites/default/files/styles/thumbnail/public/images/2023/12/05/robin_headshot_112823.jpg?itok=FJEwX_82" width="75" height="100" alt="Robin Materese poses outdoors with her dog for a casual headshot. " typeof="foaf:Image" />
</a>
</div>
</div>
<div class="nist-teaser__content-wrapper">
<header>
<h3 class="nist-teaser__title"><a href="/blogs/taking-measure/authors/robin-materese"><span>Robin Materese</span>
</a></h3>
</header>
<div class="nist-teaser__content">
<div class="text-with-summary"><p>Robin Materese is the director of web content at NIST. An aspiring journalist in college, she fell into science communications when she took a job promoting general interest science books at the National Academy of Sciences. She has also worked for a literary agency, a small PR firm, Choice Hotels, Johns Hopkins University and the National Institutes of Health. She has published three short stories in literary journals and anthologies and had a 10-minute play she wrote performed at the Source Theater in Washington, D.C. She lives in Maryland along with her husband, daughter, three dogs and two lizards.</p></div>
</div>
</div>
</article>
</div>
</div>
</div>
</div>
<div
class="views-element-container nist-block no-print"
>
<h2
class="nist-block__title"
>Related posts</h2>
<div><div class="js-view-dom-id-50486e94829d8734ceff9e667574edf0532c4ea3b62a03957d21004403b091bd">
<div>
<article
about="/blogs/taking-measure/insulation-melts-your-walls-and-could-reduce-your-energy-costs" class="nist-teaser"
>
<div class="nist-teaser__image">
<div class="entity-reference"> <a href="/blogs/taking-measure/insulation-melts-your-walls-and-could-reduce-your-energy-costs" hreflang="en"><img loading="lazy" src="/sites/default/files/styles/thumbnail/public/images/2025/01/30/jae_hyun_kim_portrait_012125.JPG?itok=JlrBhtoT" width="100" height="67" alt="A researcher in a lab coat and safety glasses poses next to a large piece of lab equipment." typeof="foaf:Image" />
</a>
</div>
</div>
<div class="nist-teaser__content-wrapper">
<header>
<h3 class="nist-teaser__title"><a href="/blogs/taking-measure/insulation-melts-your-walls-and-could-reduce-your-energy-costs"><span>The Insulation That Melts in Your Walls — and Could Reduce Your Energy Costs</span>
</a></h3>
<div class="nist-teaser__date">
<div class="daterange"><time datetime="2025-02-26T12:00:00Z">February 26, 2025</time>
</div>
</div>
</header>
<div class="nist-teaser__content">
<div class="text-with-summary"> Wherever humans go, we take some form of insulation with us to keep us at just the right temperature. But just because the idea is old doesnt mean that there
</div>
</div>
</div>
</article>
</div>
<div>
<article
about="/blogs/taking-measure/high-flying-science-how-and-why-we-sent-refrigerator-halfway-space" class="nist-teaser"
>
<div class="nist-teaser__image">
<div class="entity-reference"> <a href="/blogs/taking-measure/high-flying-science-how-and-why-we-sent-refrigerator-halfway-space" hreflang="en"><img loading="lazy" src="/sites/default/files/styles/thumbnail/public/images/2025/01/23/ephraim_gau_tes_balloon_in_air_012125.JPG?itok=vkGGerAo" width="75" height="100" alt="A rectangular box coated with reflective foil hangs from cables over a parking lot." typeof="foaf:Image" />
</a>
</div>
</div>
<div class="nist-teaser__content-wrapper">
<header>
<h3 class="nist-teaser__title"><a href="/blogs/taking-measure/high-flying-science-how-and-why-we-sent-refrigerator-halfway-space"><span>High-Flying Science: How and Why We Sent a Refrigerator Halfway to Space</span>
</a></h3>
<div class="nist-teaser__date">
<div class="daterange"><time datetime="2025-02-12T12:00:00Z">February 12, 2025</time>
</div>
</div>
</header>
<div class="nist-teaser__content">
<div class="text-with-summary"> NIST-developed tools can study the remnants of the Big Bang and more, and now researchers are working to launch these tools high above the Earths atmosphere —
</div>
</div>
</div>
</article>
</div>
<div>
<article
about="/blogs/taking-measure/5-concepts-can-help-you-understand-quantum-mechanics-and-technology-without" class="nist-teaser"
>
<div class="nist-teaser__image">
<div class="entity-reference"> <a href="/blogs/taking-measure/5-concepts-can-help-you-understand-quantum-mechanics-and-technology-without" hreflang="en"><img loading="lazy" src="/sites/default/files/styles/thumbnail/public/images/2023/10/16/tara_fortier_working_in_lab_october_2023.jpg?itok=RkM9HePP" width="100" height="67" alt="A researcher wearing safety glasses reaches into a box of circuitry and other equipment, which emits a green glow. " typeof="foaf:Image" />
</a>
</div>
</div>
<div class="nist-teaser__content-wrapper">
<header>
<h3 class="nist-teaser__title"><a href="/blogs/taking-measure/5-concepts-can-help-you-understand-quantum-mechanics-and-technology-without"><span>5 Concepts Can Help You Understand Quantum Mechanics and Technology — Without Math!</span>
</a></h3>
<div class="nist-teaser__date">
<div class="daterange"><time datetime="2025-02-05T12:00:00Z">February 5, 2025</time>
</div>
</div>
</header>
<div class="nist-teaser__content">
<div class="text-with-summary"> Quantum is everywhere, and you can understand the basic quirks of life at the quantum level … no math required.
</div>
</div>
</div>
</article>
</div>
</div>
</div>
</div>
<div
class="nist-block no-print"
>
<h2
class="nist-block__title"
>Comments</h2>
<section>
<article data-comment-user-id="0" id="comment-80861" class="nist-comment js-comment">
<footer class="nist-comment__info">
<p class="submitted">
<span class="nist-comment__author"><span lang="" typeof="schema:Person" property="schema:name" datatype="">Chase Casey</span></span>
on
<span class="nist-comment__date">February 6, 2019 9:34 PM</span>
<mark class="hidden nist-comment__new" data-comment-timestamp="1549506868"></mark>
</p>
<div class="nist-comment__permalink"><a href="#comment-80861">Permalink</a></div>
</footer>
<div class="nist-comment__content">
<div class="text-long"><p>While the proton trap is the most amazing thing on the list, all are amazing in their own way. I&#039;m so happy NIST took the time to create this list to highlight some of their many accomplishments. Maybe next year they can do a 2019 &quot;wrap up&quot; video, which would make it easier to share on social platforms. </p>
<p>NIST, I can&#039;t wait to see the next big thing you publish!</p>
</div>
<ul class="links inline nist-comment__links">
<li class="comment-reply nist-comment__link">
<a href="/comment/reply/node/1539456/comment_node_blog/80861">Reply</a></li></ul>
</div>
</article>
<div class="indented">
<article data-comment-user-id="46611" id="comment-80891" class="nist-comment js-comment">
<footer class="nist-comment__info">
<p class="submitted">
<span class="nist-comment__author"><span lang="" about="/user/46611" typeof="schema:Person" property="schema:name" datatype="" content="robin.materese@nist.gov">robin.materese@nist.gov</span></span>
on
<span class="nist-comment__date">February 7, 2019 9:30 AM</span>
<mark class="hidden nist-comment__new" data-comment-timestamp="1549549813"></mark>
<span class="nist-comment__parent">| Replied to <a href="/comment/80861#comment-80861" class="permalink" rel="bookmark" hreflang="en">While the proton trap is the</a></span>
</p>
<div class="nist-comment__permalink"><a href="#comment-80891">Permalink</a></div>
</footer>
<div class="nist-comment__content">
<div class="text-long"><p>Thanks! I&#039;ll pass on your idea of a &quot;wrap-up&quot; video to the video team for the end of this year.</p>
</div>
<ul class="links inline nist-comment__links">
<li class="comment-reply nist-comment__link">
<a href="/comment/reply/node/1539456/comment_node_blog/80891">Reply</a></li></ul>
</div>
</article>
</div>
<article data-comment-user-id="0" id="comment-80896" class="nist-comment js-comment">
<footer class="nist-comment__info">
<p class="submitted">
<span class="nist-comment__author"><span lang="" typeof="schema:Person" property="schema:name" datatype="">Chris Parisi</span></span>
on
<span class="nist-comment__date">February 7, 2019 9:59 AM</span>
<mark class="hidden nist-comment__new" data-comment-timestamp="1549551571"></mark>
</p>
<div class="nist-comment__permalink"><a href="#comment-80896">Permalink</a></div>
</footer>
<div class="nist-comment__content">
<div class="text-long"><p>As a fan of NIST, I congratulate all of your on your dedication, passion and curiosity that drives your work and your accomplishments. I am always impressed with the achievements and advancements that is see from NIST as a former chemist and InfoSec Engineer. From the kilogram to outer space, you guys rock.</p>
</div>
<ul class="links inline nist-comment__links">
<li class="comment-reply nist-comment__link">
<a href="/comment/reply/node/1539456/comment_node_blog/80896">Reply</a></li></ul>
</div>
</article>
<div class="indented">
<article data-comment-user-id="46611" id="comment-80901" class="nist-comment js-comment">
<footer class="nist-comment__info">
<p class="submitted">
<span class="nist-comment__author"><span lang="" about="/user/46611" typeof="schema:Person" property="schema:name" datatype="" content="robin.materese@nist.gov">robin.materese@nist.gov</span></span>
on
<span class="nist-comment__date">February 7, 2019 10:13 AM</span>
<mark class="hidden nist-comment__new" data-comment-timestamp="1549552403"></mark>
<span class="nist-comment__parent">| Replied to <a href="/comment/80896#comment-80896" class="permalink" rel="bookmark" hreflang="en">As a fan of NIST, I</a></span>
</p>
<div class="nist-comment__permalink"><a href="#comment-80901">Permalink</a></div>
</footer>
<div class="nist-comment__content">
<div class="text-long"><p>Thanks.</p>
</div>
<ul class="links inline nist-comment__links">
<li class="comment-reply nist-comment__link">
<a href="/comment/reply/node/1539456/comment_node_blog/80901">Reply</a></li></ul>
</div>
</article>
</div>
<article data-comment-user-id="0" id="comment-80906" class="nist-comment js-comment">
<footer class="nist-comment__info">
<p class="submitted">
<span class="nist-comment__author"><span lang="" typeof="schema:Person" property="schema:name" datatype="">Lena</span></span>
on
<span class="nist-comment__date">February 7, 2019 10:45 AM</span>
<mark class="hidden nist-comment__new" data-comment-timestamp="1549554351"></mark>
</p>
<div class="nist-comment__permalink"><a href="#comment-80906">Permalink</a></div>
</footer>
<div class="nist-comment__content">
<div class="text-long"><p>Great blog post! Very interesting.</p>
</div>
<ul class="links inline nist-comment__links">
<li class="comment-reply nist-comment__link">
<a href="/comment/reply/node/1539456/comment_node_blog/80906">Reply</a></li></ul>
</div>
</article>
<article data-comment-user-id="0" id="comment-81736" class="nist-comment js-comment">
<footer class="nist-comment__info">
<p class="submitted">
<span class="nist-comment__author"><span lang="" typeof="schema:Person" property="schema:name" datatype="">William Guin</span></span>
on
<span class="nist-comment__date">March 19, 2019 12:57 PM</span>
<mark class="hidden nist-comment__new" data-comment-timestamp="1553014667"></mark>
</p>
<div class="nist-comment__permalink"><a href="#comment-81736">Permalink</a></div>
</footer>
<div class="nist-comment__content">
<div class="text-long"><p>How fascinating the world of measurements, as a Chemical Engineer and having more than 15 years in metrology I am still in love with this science, I appreciate all the contribution of NIST and the dissemination of their scientific work, I am super fan of their publications and every day I enter your website, from the Division of Metrology of the National Institute of Normalization of Chile ... A Venezuelan contributing his experience in metrology to this beautiful country that received me kindly.</p>
</div>
<ul class="links inline nist-comment__links">
<li class="comment-reply nist-comment__link">
<a href="/comment/reply/node/1539456/comment_node_blog/81736">Reply</a></li></ul>
</div>
</article>
<h2>Add new comment</h2>
<link rel="stylesheet" media="all" href="/sites/default/files/css/css_Lx5yvw0vUi4TN7C0L-5Rdrp4Q049mXEKn-dXREWOtBs.css?delta=0&amp;language=en&amp;theme=nist_www&amp;include=eJxLzCvJTMov0U-E0Hpp-UW5OsmJBSXJGYn6SYnFqTppmTklqUX6KUWlBYk5ehAeAD47FNs&amp;exclude=eJx1UAuuwyAMuxAdR0IBsi5bIBWfdb39QrunVZOeRFDsWI7BQ3i4JnoW67-9u1fj_xlRkGxmkZnRQQbeGoVqfwmTqTZ3JeWirJkFomtFbSjPdoZjXKkhpaXIE-0vMSLsXLthQt0s7KG4JNFGquDVmCk_TN1qw6QJK-56O7N44HM_fazsDSFi-YNuXdez-oSHBF9tLLCx9AX48oHmSbhWu98XDdMZTV0gaWUr_tprgKaUBAJ2CSPByEbBMGzSm9PwQZ9XNisZg_Bh6O49LSrP_bCeBp4G_kZLFIqMH3oD_KWsjg" />
<form class="comment-comment-node-blog-form comment-form usa-form antibot" novalidate="novalidate" data-drupal-selector="comment-form" data-action="/comment/reply/node/1539456/comment_node_blog" action="/antibot" method="post" id="comment-form" accept-charset="UTF-8">
<noscript>
<div class="antibot-no-js antibot-message antibot-message-warning">You must have JavaScript enabled to use this form.</div>
</noscript>
<div class="form-item js-form-item form-type-textfield js-form-type-textfield form-item-name js-form-item-name">
<label for="edit-name" class="usa-label">
Your name
</label>
<input data-drupal-default-value="Anonymous" data-drupal-selector="edit-name" type="text" id="edit-name" name="name" value="" size="30" maxlength="60" class="form-text usa-input" />
</div>
<input data-drupal-selector="form-74edwmbbvpgywvmjijnkp8voa6ejdarxv6jhwjsrbl0" type="hidden" name="form_build_id" value="form-74edWMBbvpgYwVMjiJNKp8VOa6EjDaRXv6JhwjSrBL0" class="usa-input" /><input data-drupal-selector="edit-comment-comment-node-blog-form" type="hidden" name="form_id" value="comment_comment_node_blog_form" class="usa-input" /><input data-drupal-selector="edit-antibot-key" type="hidden" name="antibot_key" value="" class="usa-input" /><div class="field--type-text-long field--name-comment-body field--widget-text-textarea js-form-wrapper form-wrapper" data-drupal-selector="edit-comment-body-wrapper" id="edit-comment-body-wrapper"> <div class="js-text-format-wrapper js-form-item form-item">
<div class="form-item js-form-item form-type-textarea js-form-type-textarea form-item-comment-body-0-value js-form-item-comment-body-0-value">
<label for="edit-comment-body-0-value" class="usa-label form-required">
Comment
<span class="usa-label--required"> <span class="usa-sr-only">Required</span>*</span></label>
<div class="form-textarea-wrapper">
<textarea class="js-text-full text-full form-textarea required usa-textarea resize-vertical" data-entity_embed-host-entity-langcode="en" data-media-embed-host-entity-langcode="en" data-drupal-selector="edit-comment-body-0-value" id="edit-comment-body-0-value" name="comment_body[0][value]" rows="5" cols="60" placeholder="" required="required" aria-required="true"></textarea>
</div>
</div>
<div class="js-filter-wrapper filter-wrapper hidden js-form-wrapper form-wrapper" data-drupal-selector="edit-comment-body-0-format" id="edit-comment-body-0-format"><div class="js-filter-guidelines filter-guidelines js-form-wrapper form-wrapper" data-drupal-selector="edit-comment-body-0-format-guidelines" id="edit-comment-body-0-format-guidelines"><div data-drupal-format-id="plain_text">
<h4>Plain text</h4>
<ul>
<li>No HTML tags allowed.</li>
<li>Web page addresses and email addresses turn into links automatically.</li>
<li>Lines and paragraphs break automatically.</li>
</ul>
</div>
</div>
</div>
</div>
</div>
<fieldset data-drupal-selector="edit-captcha" class="captcha captcha-type-challenge--image">
<legend class="captcha__title js-form-required form-required">
CAPTCHA
</legend>
<div class="captcha__element">
<input data-drupal-selector="edit-captcha-sid" type="hidden" name="captcha_sid" value="652142321" class="usa-input" /><input data-drupal-selector="edit-captcha-token" type="hidden" name="captcha_token" value="X-6R1kHWxkAKZ3tqmbsHBWFnNi_knpV14YZj7Guitdg" class="usa-input" /><div class="captcha__image-wrapper js-form-wrapper form-wrapper" data-drupal-selector="edit-captcha-image-wrapper" id="edit-captcha-image-wrapper"><img data-drupal-selector="edit-captcha-image" src="/image-captcha-generate/652142321/1741077778" width="180" height="60" alt="Image CAPTCHA" title="Image CAPTCHA" loading="lazy" typeof="foaf:Image" />
</div>
<div class="form-item js-form-item form-type-textfield js-form-type-textfield form-item-captcha-response js-form-item-captcha-response">
<label for="edit-captcha-response" class="usa-label form-required">
What code is in the image?
<span class="usa-label--required"> <span class="usa-sr-only">Required</span>*</span></label>
<input autocomplete="off" data-drupal-selector="edit-captcha-response" aria-describedby="edit-captcha-response--description" type="text" id="edit-captcha-response" name="captcha_response" value="" size="15" maxlength="128" class="form-text required usa-input" required="required" aria-required="true" />
<div id="edit-captcha-response--description" class="description help-block">
Enter the characters shown in the image.
</div>
</div>
</div>
<div class="captcha__description description">This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.</div>
</fieldset>
<div data-drupal-selector="edit-actions" class="form-actions js-form-wrapper form-wrapper" id="edit-actions--2"><input data-drupal-selector="edit-submit" type="submit" id="edit-submit" name="op" value="Save" class="button button--primary js-form-submit form-submit usa-button" /></div>
<div class="comments__disclaimer padding-top-2">
<em>Please be respectful when posting comments. We will post all comments without editing as long as they are appropriate for a public, family friendly website, are on topic and do not contain profanity, personal attacks, misleading or false information/accusations or promote specific commercial products, services or organizations. Comments that violate our comment policy or include links to non-government organizations/web pages will not be posted.</em>
</div>
</form>
</section>
</div>
</div>
<aside class="nist-page__region nist-page__region--sidebar-second tablet-lg:grid-col-4">
<div>
<div
class="nist-block"
>
<div>
<div about="/blogs/taking-measure">
<div
class="nist-block no-print"
>
<h2
class="nist-block__title"
>Our Science in Your Inbox</h2>
<div class="text-long"><p>Subscribe to our weekly emails.</p>
<form action="https://public.govdelivery.com/accounts/USNIST/subscribers/qualify" accept-charset="UTF-8" method="post">
<input name="utf8" type="hidden" value="&#x2713;">
<input type="hidden" name="authenticity_token" value="GleKn0r3EFkuIRsIWsyLN6Mrqim4qc3U7eIUCWGqBFz2ziQ/qv0gnQTJUhVbKHMSlmrsC7UHIm6S8IfK6qk9EQ==">
<input type="hidden" name="topic_id" id="topic_id" value="USNIST_309">
<div class="grid-row grid-gap-1">
<div class="tablet:grid-col-8">
<label class="usa-sr-only" for="email">Enter Email Address</label>
<input class="usa-input" type="text" name="email" id="email" title="email" placeholder="Your Email Address">
</div>
<div class="tablet:grid-col-4">
<input type="submit" name="commit" value="Sign Up" class="usa-button margin-top-1">
</div>
</div>
</form>
</div>
</div>
<div
class="views-exposed-form usa-form filters nist-block" novalidate="novalidate" data-drupal-selector="views-exposed-form-search-blog-taking-measure-search-page"
>
<h2
class="nist-block__title"
>Search</h2>
<form action="/blogs/taking-measure/search" method="get" id="views-exposed-form-search-blog-taking-measure-search-page" accept-charset="UTF-8" class="usa-form">
<div class="form-item js-form-item form-type-textfield js-form-type-textfield form-item-k js-form-item-k form-no-label">
<input placeholder="Search this blog" data-drupal-selector="edit-k" type="text" id="edit-k" name="k" value="" size="30" maxlength="128" class="form-text usa-input" />
<div id="edit-k--description" class="description help-block">
Put exact phrase in quotes (e.g., "artificial intelligence")
</div>
</div>
<div class="grid-col-12 form-actions js-form-wrapper form-wrapper" data-drupal-selector="edit-actions" id="edit-actions"><input data-drupal-selector="edit-submit-search-blog" type="submit" id="edit-submit-search-blog" value="Search" class="button js-form-submit form-submit usa-button" /></div>
</form>
</div>
<div
class="nist-block no-print"
>
<h2
class="nist-block__title"
>Stay connected</h2>
<div><a href="https://www.facebook.com/nist" class="nist-social nist-social--facebook" title="Facebook" ><span>Facebook</span></a><a href="https://www.linkedin.com/company/nist" class="nist-social nist-social--linkedin" title="LinkedIn" ><span>LinkedIn</span></a><a href="https://www.x.com/nist" class="nist-social nist-social--x" title="X (Twitter)" ><span>X (Twitter)</span></a><a href="https://www.youtube.com/nist" class="nist-social nist-social--youtube" title="Youtube" ><span>Youtube</span></a><a href="https://www.instagram.com/nist/" class="nist-social nist-social--instagram" title="Instagram" ><span>Instagram</span></a><a href="https://public.govdelivery.com/accounts/USNIST/subscriber/new?topic_id=USNIST_309" class="nist-social nist-social--envelope" title="GovDelivery" ><span>GovDelivery</span></a></div>
</div>
<div
class="views-element-container nist-block"
>
<h2
class="nist-block__title"
>Categories</h2>
<div><div class="js-view-dom-id-59857ad44a524ebf5440910c26871b1b385489e6e1297b76cb7ecc1726a63711">
<div>
<select class="usa-select ViewsJumpMenu js-viewsJumpMenu" title="-- Choose --" id="blog-categories-takingm-jump-menu">
<option>-- Choose --</option>
<option data-url="/blogs/taking-measure/categories/249466">Advanced communications</option>
<option data-url="/blogs/taking-measure/categories/248321">Bioscience</option>
<option data-url="/blogs/taking-measure/categories/248371">Buildings and Construction</option>
<option data-url="/blogs/taking-measure/categories/248416">Chemistry</option>
<option data-url="/blogs/taking-measure/categories/248486">Electronics</option>
<option data-url="/blogs/taking-measure/categories/248531">Energy</option>
<option data-url="/blogs/taking-measure/categories/248561">Environment</option>
<option data-url="/blogs/taking-measure/categories/248586">Fire</option>
<option data-url="/blogs/taking-measure/categories/248616">Forensic Science</option>
<option data-url="/blogs/taking-measure/categories/248651">Health</option>
<option data-url="/blogs/taking-measure/categories/249421">Information technology</option>
<option data-url="/blogs/taking-measure/categories/2748236">Infrastructure</option>
<option data-url="/blogs/taking-measure/categories/248866">Manufacturing</option>
<option data-url="/blogs/taking-measure/categories/248946">Materials</option>
<option data-url="/blogs/taking-measure/categories/249011">Mathematics and statistics</option>
<option data-url="/blogs/taking-measure/categories/249051">Metrology</option>
<option data-url="/blogs/taking-measure/categories/249126">Nanotechnology</option>
<option data-url="/blogs/taking-measure/categories/249451">Neutron research</option>
<option data-url="/blogs/taking-measure/categories/249426">Performance excellence</option>
<option data-url="/blogs/taking-measure/categories/249241">Physics</option>
<option data-url="/blogs/taking-measure/categories/249461">Public safety</option>
<option data-url="/blogs/taking-measure/categories/249456">Resilience</option>
<option data-url="/blogs/taking-measure/categories/249341">Standards</option>
<option data-url="/blogs/taking-measure/categories/2813456">Technology transfer</option>
<option data-url="/blogs/taking-measure/categories/249396">Transportation</option>
</select>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</aside>
</div>
</div>
<div class="grid-container">
</div>
</section>
</div>
<div data-elastic-exclude>
<!-- nist-index-ignore-start -->
<footer class="nist-footer padding-bottom-4">
<div class="grid-container nist-footer__info">
<div class="grid-row">
<div class="tablet:grid-col-6">
<div class="nist-footer__logo">
<a href="/" title="National Institute of Standards and Technology" rel="home">
<img class="nist-footer__logo-img" src="/libraries/nist-component-library/dist/img/logo/NIST-Logo-Brand-White.svg" alt="National Institute of Standards and Technology logo" width="300px" height="42px" />
</a>
</div>
<div class="nist-footer__contact">
<h3 class="nist-footer__contact-heading">HEADQUARTERS</h3>
<address>
100 Bureau Drive<br>
Gaithersburg, MD 20899<br>
<a href="tel:301-975-2000">301-975-2000</a>
</address>
<p>
<a href="mailto:do-webmaster@nist.gov">Webmaster</a> | <a href="https://www.nist.gov/about-nist/contact-us">Contact Us</a> | <a href="https://www.nist.gov/visit">Our Other Offices</a>
</p>
</div>
</div>
<div class="tablet:grid-col-6">
<div class="nist-footer__social-links">
<a class="nist-social nist-social--x-white" href=" https://x.com/NIST">
<span>X.com</span>
</a>
<a class="nist-social nist-social--facebook-white" href=" https://www.facebook.com/NIST">
<span>Facebook</span>
</a>
<a class="nist-social nist-social--linkedin-white" href=" https://www.linkedin.com/company/nist">
<span>LinkedIn</span>
</a>
<a class="nist-social nist-social--instagram-white" href=" https://www.instagram.com/nist/">
<span>Instagram</span>
</a>
<a class="nist-social nist-social--youtube-white" href=" https://www.youtube.com/NIST">
<span>YouTube</span>
</a>
<a class="nist-social nist-social--giphy-white" href=" https://giphy.com/nist">
<span>Giphy</span>
</a>
<a class="nist-social nist-social--rss-white" href=" https://www.nist.gov/news-events/nist-rss-feeds">
<span>RSS Feed</span>
</a>
<a class="nist-social nist-social--envelope-white" href=" https://public.govdelivery.com/accounts/USNIST/subscriber/new">
<span>Mailing List</span>
</a>
</div>
<div class="nist-footer__feedback">
How are we doing? <a class="usa-button" rel="nofollow" href="/form/nist-gov-feedback?destination=/blogs/taking-measure/top-nist-images-2018" title="Provide feedback">Feedback</a>
</div>
</div>
</div>
</div>
<div class="grid-container">
<div class="nist-footer__nav" role="navigation">
<ul>
<li class="nist-footer__menu-item">
<a href="https://www.nist.gov/privacy-policy">Site Privacy</a>
</li>
<li class="nist-footer__menu-item">
<a href="https://www.nist.gov/oism/accessibility">Accessibility</a>
</li>
<li class="nist-footer__menu-item">
<a href="https://www.nist.gov/privacy">Privacy Program</a>
</li>
<li class="nist-footer__menu-item">
<a href="https://www.nist.gov/oism/copyrights">Copyrights</a>
</li>
<li class="nist-footer__menu-item">
<a href="https://www.commerce.gov/vulnerability-disclosure-policy">Vulnerability Disclosure</a>
</li>
<li class="nist-footer__menu-item">
<a href="https://www.nist.gov/no-fear-act-policy">No Fear Act Policy</a>
</li>
<li class="nist-footer__menu-item">
<a href="https://www.nist.gov/office-director/freedom-information-act">FOIA</a>
</li>
<li class="nist-footer__menu-item">
<a href="https://www.nist.gov/environmental-policy-statement">Environmental Policy</a>
</li>
<li class="nist-footer__menu-item">
<a href="https://www.nist.gov/summary-report-scientific-integrity">Scientific Integrity</a>
</li>
<li class="nist-footer__menu-item">
<a href="https://www.nist.gov/nist-information-quality-standards">Information Quality Standards</a>
</li>
<li class="nist-footer__menu-item">
<a href="https://www.commerce.gov/">Commerce.gov</a>
</li>
<li class="nist-footer__menu-item">
<a href="http://www.science.gov/">Science.gov</a>
</li>
<li class="nist-footer__menu-item">
<a href="http://www.usa.gov/">USA.gov</a>
</li>
<li class="nist-footer__menu-item">
<a href="https://vote.gov/">Vote.gov</a>
</li>
</ul>
</div>
</div>
</footer>
<!-- nist-index-ignore-end -->
</div>
</div>
<script type="application/json" data-drupal-selector="drupal-settings-json">{"path":{"baseUrl":"\/","pathPrefix":"","currentPath":"node\/1539456","currentPathIsAdmin":false,"isFront":false,"currentLanguage":"en"},"pluralDelimiter":"\u0003","suppressDeprecationErrors":true,"back_to_top":{"back_to_top_button_trigger":100,"back_to_top_speed":1200,"back_to_top_prevent_on_mobile":false,"back_to_top_prevent_in_admin":true,"back_to_top_button_type":"image","back_to_top_button_text":"Back to top"},"google_analytics":{"account":"G-HEQ0YF2VYL","trackOutbound":true,"trackMailto":true,"trackTel":true,"trackDownload":true,"trackDownloadExtensions":"7z|aac|arc|arj|asf|asx|avi|bin|bsh|c|csv|doc(x|m)?|dot(x|m)?|dw(fx|g|gd)|dxf|eps|epub|exe|f(90)|flv|gif|gz|gzip|hqx|jar|jpe?g|js|m1v|mp(2|3|4|e?g)|mobi|mov(ie)?|msi|msp|pdf|phps|pl|png|ppt(x|m)?|pot(x|m)?|pps(x|m)?|ppam|sld(x|m)?|thmx|qtm?|ra(m|r)?|rfa|rtf|rvt|sch|sea|sit|swf|tar|tgz|tif|txt|txz|wav|wma|wmv|wpd|wrl|xls(x|m|b)?|xlt(x|m)|xlam|xml|xsd|z|zip"},"nist_search":{"clickTracking":"search-report-click","isDebug":false,"clickTrackEnabled":true,"message":"NIST Search in debug mode. Check the browsers network inspector for Click Track reporting results..."},"data":{"extlink":{"extTarget":false,"extTargetNoOverride":false,"extNofollow":false,"extNoreferrer":false,"extFollowNoOverride":false,"extClass":"ext","extLabel":"(link is external)","extImgClass":false,"extSubdomains":true,"extExclude":"\\.gov\\\/|\\.mil\\\/|\\manufacturingusa\\.com\\\/","extInclude":"","extCssExclude":".ck-editor, .nist-video-thumbnail__lightbox-trigger, a.nist-icon--mail-blue","extCssExplicit":"","extAlert":true,"extAlertText":"Thank you for visiting NIST. We hope your visit was informative. We have provided a link to this site because it has information that may be of interest to our users. NIST does not necessarily endorse the views expressed or the facts presented on this site. Further, NIST does not endorse any commercial products that may be advertised or available on this site. Click OK to be directed to your link.","mailtoClass":"0","mailtoLabel":"(link sends email)","extUseFontAwesome":false,"extIconPlacement":"after","extFaLinkClasses":"fa fa-external-link","extFaMailtoClasses":"fa fa-envelope-o","whitelistedDomains":[]}},"viewsJumpMenu":{"blog-categories-takingm-jump-menu":{"new_window":false}},"ajaxTrustedUrl":{"\/blogs\/taking-measure\/search":true,"\/comment\/reply\/node\/1539456\/comment_node_blog":true},"user":{"uid":0,"permissionsHash":"bd6a443844dbe99b4e6942f3b1397526e760137efd2b1ee6b2d588fc414dff20"},"antibot":{"forms":{"comment-form":{"id":"comment-form","key":"8s3HerPNUiBWAup-NU0eICdfN5XSJ1VRGAW7gyEytXD"}}}}</script>
<script src="/sites/default/files/js/js_jDaFaXhHm6gPUKstNYX9eIyoQXghVs3g7rbR0QoqpYY.js?scope=footer&amp;delta=0&amp;language=en&amp;theme=nist_www&amp;include=eJxdkAuOwyAMRC8E9ZGQCQ51CzgCp2lvX8hHu6qEBG8Yz0j2OD2dSj8L-L-3ezQTRWIihwXTR3lq8CuYwk3dzF0LspUkGJzWHsIlQsTju7ES56XKi-BXGC27pnfK1HsleawuS4DADX0PTlyeuwdiEo_JniNwJwxUL3Tbtv1z0FvHIIS6LphuJ5pJcqail3yi9R_7YtqoHskZY-GZJzPE5h5rXlz3rbCzHWwHGyzKXhTO-zZLzaavQ6leFQd9AQAFjIc"></script>
<script src="https://siteimproveanalytics.com/js/siteanalyze_6017546.js" async></script>
<script src="/sites/default/files/js/js_phYs2jDctfdGpas0b2o3STtb7Y4B0bPDz-8rro3OgSg.js?scope=footer&amp;delta=2&amp;language=en&amp;theme=nist_www&amp;include=eJxdkAuOwyAMRC8E9ZGQCQ51CzgCp2lvX8hHu6qEBG8Yz0j2OD2dSj8L-L-3ezQTRWIihwXTR3lq8CuYwk3dzF0LspUkGJzWHsIlQsTju7ES56XKi-BXGC27pnfK1HsleawuS4DADX0PTlyeuwdiEo_JniNwJwxUL3Tbtv1z0FvHIIS6LphuJ5pJcqail3yi9R_7YtqoHskZY-GZJzPE5h5rXlz3rbCzHWwHGyzKXhTO-zZLzaavQ6leFQd9AQAFjIc"></script>
<script type="text/javascript">window.NREUM||(NREUM={});NREUM.info={"beacon":"bam.nr-data.net","licenseKey":"37b7ccb661","applicationID":"1089704227","transactionName":"YFxUN0sADEdYVkBaClkWdwBNCA1aFnFGRhVWVWoNVgUHaHpaWkcXWFVaBks9LFtdUGJaAEB6WQ1NEw1YVVBGHltBUFMU","queueTime":4,"applicationTime":1267,"atts":"TBtXQQMaH0k=","errorBeacon":"bam.nr-data.net","agent":""}</script></body>
</html>