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Standards

Reference instruments

News and Updates

Events

Blog Posts

Title card reads "A Scientific Christmas Tale" with the NIST logo in a wreath and flashing holiday lights.

A Scientific Christmas Tale

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An antique clock showing a few minutes before 12 is topped with a party hat, and colorful streamers hang in the background.

Auld Lang ‘Time’: One of the Country’s Timekeepers Makes Sure We Ring in The New Year at Just the Right Second

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A researcher wearing safety glasses reaches into a box of circuitry and other equipment, which emits a green glow.

Think You Know What a Second Is? It Will Likely Change in the Next Decade.

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Projects and Programs

Sensing and Imaging of concealed objects

Ongoing
Threats to personal and collective safety abound in our society. The Security Technologies Group (STG) performs research to advance the technology and measurement science of security imaging and sensing. This work includes the establishment of test and evaluation tools, reference test beds, test
Illustration of satellite sensing of sunlight reflected by buildings, roads, water and trees to assess radiative warming of the earth.

Climate Science

Ongoing
This program encompasses multifaceted efforts to advance the metrology of climate science. Projects include: development of ultra-high accuracy optical standards and technologies to determine greenhouse gases (GHGs) concentrations, atmospheric lifetimes, and aerosol radiative forcing development of
A chart showing the various sectors served by the Laser Power & Energy Meter calibrations project as of 2025

Laser Power and Energy Meter Calibrations

Ongoing
We serve Industry, DoD, and research institutions by calibrating instruments used to measure the power or energy emitted by a laser, or single photon source. From Single Photons to Kilowatts, Longwave Infrared to Deep Ultraviolet, Free-space and Fiber, we can calibrate your instruments. The chart to

Publications

Feature Description for Assessing Autonomous Vehicle Performance

Author(s)
Edward Griffor, Hadhoum Hajjaj, Thoshitha Gamage, Thomas Roth, Wenqi Guo
This technical report presents a structured methodology for describing and assessing auto-mated vehicle (AV) features, with a focus on ensuring consistent and

Single-cryostat integration of the quantum anomalous Hall and Josephson effects

Author(s)
Jason Underwood, Linsey Rodenbach, Ngoc Thanh Mai Tran, Alireza Panna, Zachary Barcikowski, Molly Andersen, Peng Zhang, Lixuan Tai, Randolph Elmquist, Dean Jarrett, David Goldhaber-Gordon, David Newell, Albert Rigosi
By directly integrating a quantum anomalous Hall resistor (QAHR) and a programmable Josephson voltage standard (PJVS) into a single cryostat, we have

Tools and Instruments

Large Aperture Scanner

Large Aperture Scanner

The Large Aperture Scanner (LAS) scans a radar transceiver over a 5 meter by 20 meter aperture. Image reconstruction techniques enable a three-dimensional
Reference Ballistic Chronograph Figure 1

Reference Ballistic Chronograph

The NIST-developed reference ballistic chronograph (RBC) provides repeatable measurements of the speed of a bullet that will impact a test article, such as