Long-term changes in the rotation of the Earth : 700 B.C. to A.D. 1980

  title={Long-term changes in the rotation of the Earth : 700 B.C. to A.D. 1980},
  author={Francis Richard Stephenson and Leslie V. Morrison},
  journal={Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences},
  pages={47 - 70}
  • F. Stephenson, L. Morrison
  • Published 27 November 1984
  • Physics
  • Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences
Occultations of stars by the Moon, and solar and lunar eclipses are analysed for variations in the Earth’s rotation over the past 2700 years. Although tidal braking provides the dominant, long-term torque, it is found that the rate of rotation does not decrease uniformly as would be expected if tidal friction were the only mechanism affecting the Earth’s rotation. There are also non-tidal changes present that vary on timescales ranging from decades to millennia. The magnitudinal and temporal… Expand

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