Shooting the Moon: a look at lunar laser ranging and what it tells us about the Earth-Moon system and the interior of the Moon
Explore the source record for details and available documents.
LLR lunar interior Moon lunar laser ranging↗
SEARCH · Search NASA
Results for “LLR”
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
A Combination of Earth Orientation Observations: SPACE93
Explore the source record for details and available documents.
Kalman filter very long baseline interferometry (V↗
Lunar Laser Ranging Science: Gravitational Physics and Lunar Interior and Geodesy
Laser pulses fired at retroreflectors on the Moon provide very accurate ranges. Analysis yields information on Earth, Moon, and orbit. The highly accurate retroreflector positions have uncertainties less than a meter. Tides on the Moon show strong dissipation, with Q=33+/-4 at a month and a weak dependence on period. Lunar rotation depends on interior properties; a fluid core is indicated with radius approx.20% that of the Moon. Tests of relativistic gravity verify the equivalence principle to +/-1.4x10(exp -13), limit deviations from Einstein's general relativity, and show no rate for the gravitational constant G/G with uncertainty 9x10(exp -13)/yr.
relativity↗
Combination of Earth Orientation Measurements: SPACE95, COMB95, and POLE95
NOne. This is a set of viewgraph print outs for a presentation for the 1996 Spring Meeting of the American Geophysical Union. The presentation concerned using a Kalman filter to combine independently determined Earth orientation measurements from all modern, space-geodetic techniques.
Kalman↗
Data Reduction and Calibration of the Apache Point Observatory Lunar Laser-ranging Operation
Explore the source record for details and available documents.
LLR↗
Recent Developments of the Apache Point Lunar Laser Ranging Station
Explore the source record for details and available documents.
LLR↗
Fifteen Years of Millimeter Accuracy Lunar Laser Ranging with APOLLO: Data Reduction and Calibration
The Apache Point Lunar Laser-ranging Operation (APOLLO) has been collecting lunar range measurements for 15 yr at millimeter accuracy. The median nightly range uncertainty since 2006 is 1.7 mm. A recently added Absolute Calibration System (ACS), providing an independent assessment of APOLLO system accuracy and the capability to correct lunar range data, revealed a ∼0.4% (10 ps) systematic error in the calibration of one piece of hardware that has been present for the entire history of APOLLO. The application of ACS-based timing corrections suggests systematic errors are reduced to <1 mm, such that overall data accuracy and precision are both ∼1 mm. This paper describes the processing of APOLLO/ACS data that converts photon-by-photon range measurements into the aggregated normal points that are used for science analyses. Additionally, we present methodologies to estimate timing corrections for range data lacking contemporaneous ACS photons, including range data collected prior to installation of the ACS. We also provide access to the full 15 yr archive of APOLLO normal points (2006 April 6–2020 December 27).
LLR↗