Figures of the Article

• Retro-reflector positions on the Moon^[5].
• Apollo 11 laser retro-reflector arrays.
• Apollo 14 laser retro-reflector arrays.
• Apollo 15 laser retro-reflector arrays.
• The distribution of retro-reflectors in the LLR dataset.
• Top panel: Data-Model agreement (line with points) as quantified by the RMS of the post-fit residuals of LLR data with the JPL solar system ephemeris model. Bottom panel: A stacked histogram that displays the annual count of normal point data generated by each LLR station^[10].
• Distribution of LLR session duration.
• Probability density distribution of LLR session duration.
• The distribution of LLR data format in the LLR dataset.
• Looking north along the escarpment at APO, the prominent dome silhouetted against the sky contains the LLR 3.5 m telescope. Behind and to the right of it stands the white, cone-shaped SUNSPOT solar telescope^[11].
• The distribution of lunar retro-reflectors in the APOLLO dataset.
• The distribution of uncertainty in the APOLLO dataset.
• The ACS enclosure houses a laser, which emits a sequence of 1064 nm pulses, each lasting 10 ps, into an optical fiber. The laser repetition-rate controller, specifically the Microsemi 5071A, synchronizes the fiber laser with a cesium frequency standard. A universal counter, the Agilent 53132A, is used to compare the frequency of the cesium clock with that of a clock regulated by Global Positioning System (GPS) data, the TrueTime XL-DC. The dashed line in the diagram indicates temporary and intermittent adjustments made to observe the growing phase discrepancy between the two clocks^[13].
• The distribution of precision of returned photons in the Grasse dataset.
• The distribution of uncertainty in the Grasse dataset for LLR using different laser wavelengths.
• The distribution of number of returned photons in the Grasse dataset using different laser wavelengths.
• Repartition of normal points during the synodic month^[16].
• LLR being performed at YNAO.
• Residuals of the measurement data of the YNAO LLR.