clockobservatory

AnofficialwebsiteoftheUnitedStatesgovernment.Here'showyouknow.NationalInstituteofStandardsandTechnology/OFFICIALUSTIME.,TheUSNOMasterClockistheunderlyingproductforallofourprecisetimeandtimeintervalproducts.Thetimingreferenceproducedbythistimingensemble ...USNOMasterClockDescription·USNOAlternateMasterClock·HydrogenMasers,TheU.S.NavalObservatory(USNO)providesawiderangeofastronomicaldataandprodu...

參考資訊如下
NIST (time.gov)

An official website of the United States government. Here's how you know. National Institute of Standards and Technology/ OFFICIAL US TIME.

The USNO Master Clock

The USNO Master Clock is the underlying product for all of our precise time and time interval products. The timing reference produced by this timing ensemble ... USNO Master Clock Description · USNO Alternate Master Clock · Hydrogen Masers

U.S. Naval Observatory

The U.S. Naval Observatory (USNO) provides a wide range of astronomical data and products, and serves as the official source of time for the U.S. Department ...

Web Clock｜Hong Kong Observatory(HKO)｜Time Services

Web clock to display Hong Kong time.

網上時鐘｜香港天文台(HKO)

網上時鐘顯示香港時間.

Clocks and timekeeping

Royal Observatory Greenwich holds a treasure trove of some of history's most iconic timepieces. Discover the stories behind John Harrison's groundbreaking ...

Time.gov

An official website of the United States government. Here's how you know. National Institute of Standards and Technology/ OFFICIAL US TIME.