File:Usno-mc.jpg

Usno-mc.jpg ‎(600 × 357 pixels, file size: 36 KB, MIME type: image/jpeg)

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Summary

Description	English: US Naval Observatory's (USNO) Master Clock Ensemble, Washington D.C., made up of a large number of Symmetricom 5071A cesium beam clocks (rack in background). This provides the time standard for the US military. The large black object in the foreground is a Symmetricom (formerly Sigma-Tau) MHM-2010 active hydrogen maser.
Date	20 December 2008 (original upload date)
Source	http://tycho.usno.navy.mil/gif/clockvaults.jpg
Author	US Naval Observatory
Permission ( Reusing this file)	Per source's Security & Privacy Policy: "All information on this site is public domain and may be distributed or copied unless otherwise specified. Use of appropriate byline/photo/image credits is requested."

Licensing

	This file is a work of a sailor or employee of the U.S. Navy, taken or made as part of that person's official duties. As a work of the U.S. federal government, the image is in the public domain.
	This file has been identified as being free of known restrictions under copyright law, including all related and neighboring rights.

File usage

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Caesium

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