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Published on: February 12, 2013
Earth rotation measured by lunar laser ranging
Science (New York, N.Y.)
|September 10, 1976
Summary
This study measured Earth's rotation with high accuracy, finding results consistent with established astronomical data. Analysis revealed minimal evidence of rapid changes in Earth's rotational speed.
Area of Science:
- Geophysics
- Astronomy
- Earth Science
Background:
- Accurate measurement of Earth's rotation is crucial for various scientific and navigational applications.
- Previous methods for determining Earth's angular position had limitations in precision and temporal resolution.
Purpose of the Study:
- To assess the accuracy of single-day determinations of Earth's angular position.
- To compare new measurements with established astronomical data and evaluate Earth's rotational stability.
Main Methods:
- Analysis of 194 single-day measurements of Earth's angular position in space.
- Comparison of results with 5-day averages from the Bureau International de l'Heure (BIH).
Main Results:
- Median accuracy of single-day determinations was 0.7 milliseconds (0.01 arc seconds).
- Measurements showed agreement with BIH data within expected uncertainties (2 milliseconds).
- No significant evidence for rapid variations in Earth's rotation was detected.
Conclusions:
- The employed method provides a highly accurate determination of Earth's orientation.
- Earth's rotation appears stable, with no substantial rapid variations observed in the analyzed data.
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