Laser ranging data consist of the station to satellite distance and time (round-trip) resulting from the firing of a laser to a retroreflector-equipped satellite. The raw laser ranges are corrected and formatted at the observing station. These data corrections include atmospheric parameters, ground target calibration values, etc. The ILRS laser ranging data are available in two forms: full-rate (original observations with corrections) and normal points (condensed range observations generated from the original observations collected over several seconds to minutes).

The ILRS data centers also maintain an archive of lunar laser ranging (LLR) data from stations ranging to retroreflectors placed on the Moon by NASA Apollo and Russia Lunakod missions in the 1969 to 1973 time period. A small subset of stations in the ILRS network has systems capable of ranging to (and obtaining returns from) lunar distances. Scientists analyzing LLR data study the dynamics and structure of the Moon, its rate of rotation, and orbit, as well as gravitational physics and general relativity.

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