Editing Lunar Laser Ranging experiments (section)

== Data analysis ==
The Lunar Laser Ranging data is collected in order to extract numerical values for a number of parameters. Analyzing the range data involves dynamics, terrestrial geophysics, and lunar geophysics. The modeling problem involves two aspects: an accurate computation of the lunar orbit and lunar orientation, and an accurate model for the time of flight from an observing station to a retroreflector and back to the station. Modern Lunar Laser Ranging data can be fit with a 1&nbsp;cm weighted rms residual.

* The center of Earth to center of Moon distance is computed by a program that numerically integrates the lunar and planetary orbits accounting for the gravitational attraction of the Sun, planets, and a selection of asteroids.<ref name=":4">{{Cite journal|last1=Pavlov|first1=Dmitry A.|last2=Williams|first2=James G.|last3=Suvorkin|first3=Vladimir V.|date=2016|title=Determining parameters of Moon's orbital and rotational motion from LLR observations using GRAIL and IERS-recommended models|url=http://link.springer.com/10.1007/s10569-016-9712-1|journal=Celestial Mechanics and Dynamical Astronomy|language=en|volume=126|issue=1|pages=61–88|doi=10.1007/s10569-016-9712-1|issn=0923-2958|arxiv=1606.08376|bibcode=2016CeMDA.126...61P|s2cid=119116627}}</ref><ref name=":3" />
* The same program integrates the 3-axis orientation of the Moon called physical [[Libration]].

The range model includes<ref name=":4" /><ref>{{Cite web|last1=Williams|first1=James G.|last2=Boggs|first2=Dale H.|date=2020|title=The JPL Lunar Laser range model 2020|url=https://ssd.jpl.nasa.gov/ftp/eph/planets/ioms/|access-date=2021-06-01|website=ssd.jpl.nasa.gov}}</ref>

* The position of the ranging station accounting for motion due to [[plate tectonics]], [[Earth's rotation|Earth rotation]], [[Axial precession|precession]], [[nutation]], and [[polar motion]].
* Tides in the solid Earth and seasonal motion of the solid Earth with respect to its [[center of mass]].
* Relativistic transformation of time and space coordinates from a frame moving with the station to a frame fixed with respect to the solar system center of mass. Lorentz contraction of the Earth is part of this transformation.
* Delay in the Earth's atmosphere.
* Relativistic delay due to the gravity fields of the Sun, Earth, and Moon.
* The position of the retroreflector accounting for orientation of the Moon and solid-body tides.
* [[Length contraction|Lorentz contraction]] of the Moon.
* [[Thermal expansion]] and contraction of the retroreflector mounts.

For the terrestrial model, the IERS Conventions (2010) is a source of detailed information.<ref>{{Cite web|title=IERS - IERS Technical Notes - IERS Conventions (2010)|url=https://www.iers.org/IERS/EN/Publications/TechnicalNotes/tn36.html|access-date=2021-06-01|website=www.iers.org}}</ref>