Simulated DLLR data for timespan 1970 - 2021

Differential Lunar Laser Ranging (DLLR) is a new concept which will be implemented at the Table Mountain Observatory of JPL. A DLLR station will measure a lunar reflector at time t1 to get a range measurement. After a short switching interval (e.g., 1.5 min), the same station at time t2 will measure another reflector to get another range. The DLLR observation will be obtained by the difference of the two consecutive range measurements, called lunar range difference. As no actual DLLR data is available now, we did the DLLR simulation based on modifying the LLR simulation software of Hofmann (2017).

The simulated DLLR data is simulated according to the real Lunar Laser Ranging (LLR) 28093 normal points from 1970 to 2021 provided by the stations McDonald, MLRS1, MLRS2, OCA, WLRS, MLRO, APOLLO and LURE for the reflectors Apollo 11, Apollo 14, Apollo 15, Lunokhod 1 and 2. The data distribution, the assumed stations and reflectors used for DLLR simulation are the same as those of the real LLR data group. We simulated four DLLR data groups, two with 1.5-minute switching interval, two with 15-minute switching interval. Each switching interval group includes two subgroups with different observation accuracies. One is the same as the LLR range accuracy and another one is 200 times improved based on LLR range accuracy. For this DLLR simulation, the used temperature, pressure, wavelength and humidity of the station are the same for the two measurement time points t1 and t2.

The respective columns of the data contain the following information:

1. station CODE
2. measuring time t1 [JD]
3. reflector 1
4. reflector 2
5. range difference [km]
6. accuracy [um]
7. temperature[ Celsius degree]
8. pressure [hPa]
9. wavelength [um]
10. humidity [%]

A detailed description of the simulation process and the analysis of the data sets is published as "Characteristics of differential lunar laser ranging, Astronomy & Astrophysics, in review, 2022".

As the simulated data is still under scientific investigation, the data sets are of a preliminary nature and show work in progress at the Institute of Geodesy at Leibniz University Hannover.

Hofmann, F. (2017), Lunar Laser Ranging – verbesserte Modellierung der Monddynamik und Schätzung relativistischer Parameter, PhD thesis, Leibniz University Hannover.