Eclipses and the Earth’s Rotation

Autor: L. V. Morrison, F. R. Stephenson, C. Y. Hohenkerk
Rok vydání: 2018
Předmět:
Zdroj: Proceedings of the International Astronomical Union. 14:160-162
ISSN: 1743-9221
1743-9213
DOI: 10.1017/s1743921319003971
Popis: Analysis of historical records of eclipses of the Sun and Moon between 720 BC and AD 1600 gives a measure of the time difference, TT − UT = ΔT. The first derivative in time along a smooth curve fitted to the values of Δ T measures the changes in the length of the day (lod). The average rate of change of the lod is found to be significantly less than that expected on the basis of tidal friction. Fluctuations on a time-scale of centuries to millennia are mainly attributed to the effects of post-glacial uplift and core-mantle coupling.
Databáze: OpenAIRE