The Moon’s physical librations and determination of their free modes

  title={The Moon’s physical librations and determination of their free modes},
  author={N. Rambaux and James G. Williams},
  journal={Celestial Mechanics and Dynamical Astronomy},
The Lunar Laser Ranging experiment has been active since 1969 when Apollo astronauts placed the first retroreflector on the Moon. The data accuracy of a few centimeters over recent decades, joined to a new numerically integrated ephemeris, DE421, encourages a new analysis of the lunar physical librations of that ephemeris, and especially the detection of three modes of free physical librations (longitude, latitude, and wobble modes). This analysis was performed by iterating a frequency analysis… Expand

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