Unlocking complex workings of the biological clock

Scientists want to increase their understanding of circadian rhythms, those internal 24-hour biological clock cycles of sleeping and waking that occur in organisms, ranging from humans to plants to fungi to bacteria. A research ...

Physicists report on first programmable quantum sensor

Atomic clocks are the best sensors mankind has ever built. Today, they can be found in national standards institutes or satellites of navigation systems. Scientists all over the world are working to further optimize the precision ...

ESA determines new 'space time'

Since November 2021, ESA's satellites and ground stations have been running on a newly defined, incredibly precise "ESOC time." Measured by two atomic clocks in the basement of the ESOC mission control center in Germany, ...

Minimizing laser phase noise with machine learning

Ultra-precise lasers can be used for optical atomic clocks, quantum computers, power cable monitoring, and much more. But all lasers make noise, which researchers from DTU Fotonik want to minimize using machine learning.

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Atomic clock

An atomic clock is a type of clock that uses an atomic resonance frequency standard as its timekeeping element. They are the most accurate time and frequency standards known, and are used as primary standards for international time distribution services, and to control the frequency of television broadcasts and GPS satellite signals.

Atomic clocks do not use radioactivity, but rather the precise microwave signal that electrons in atoms emit when they change energy levels. Early atomic clocks were masers with attached equipment. Currently the most accurate atomic clocks are based on absorption spectroscopy of cold atoms in atomic fountains such as the NIST-F1.

National standards agencies maintain an accuracy of 10-9 seconds per day (approximately 1 part in 1014), and a precision set by the radio transmitter pumping the maser. The clocks maintain a continuous and stable time scale, International Atomic Time (TAI). For civil time, another time scale is disseminated, Coordinated Universal Time (UTC). UTC is derived from TAI, but synchronized, by using leap seconds, to UT1, which is based on actual rotations of the earth with respect to the mean sun.

This text uses material from Wikipedia, licensed under CC BY-SA