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


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)
Author US Naval Observatory
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