On a Periodic Fluctuation in the Length of the Day

Abstract

From a study of the performance of a number of quartz-crystal clocks employed in the Greenwich Time Service an annual periodic fluctuation in the length of the day is deduced. The variation is of the order of |$\pm{0}^\text{s}.001$| and has an accumulative effect in time of approximately |$\pm{0}^\text{s}.060$|⁠. This is in very close agreement with results obtained from independent data by N. Stoyko and demonstrates the persistent character of the phenomenon.