JST (Japan Standard Time)
jst
JST (Japan Standard Time) is the standard time of Japan at UTC+9, based on the 135th meridian east. Japan does not observe daylight saving time.
NICT (National Institute of Information and Communications Technology)
nict
Overview
NICT (National Institute of Information and Communications Technology) is the Japanese national research and development agency that manages Japan Standard Time. Headquartered in Koganei, Tokyo, it operates 18 cesium atomic clocks along with hydrogen maser clocks to generate and maintain JST.
Time Distribution
NICT distributes Japan Standard Time through several channels: the JJY longwave radio signal (Otakadoya-yama at 40 kHz, Hagane-yama at 60 kHz), NTP servers (ntp.nict.jp) for internet-based synchronization, and the telephone time service (dial 117). NICT also contributes atomic clock data to the BIPM for the computation of International Atomic Time (TAI).
Time-Related Research
NICT is a world leader in optical lattice clock research. Its work spans ultra-precise time generation using strontium optical lattice clocks, remote time comparison via optical fiber links, and international time transfer using satellites. These next-generation timing technologies may eventually make optical lattice clocks the primary standard for JST.
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Related Terms
Atomic Clock
atomic clock
An atomic clock measures time by using the quantum-mechanical transition frequency of atoms as its reference, achieving accuracies on the order of one second in hundreds of millions of years and forming the backbone of modern timekeeping.
NTP (Network Time Protocol)
ntp
A networking protocol for clock synchronization between computer systems over packet-switched networks.
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