Planetary and lunar ephemerides, lunar laser ranging, and lunar physical librations

Lunar laser ranging

Lunar laser ranging has provided many of the best tests of gravitation since the first Apollo astronauts landed on the Moon. The march to higher precision continues to this day, now entering the millimeter regime, and promising continued improvement in scientific results. This review introduces key aspects of the technique, details the motivations, observables, and results for a variety of scie...

APOLLO: Multiplexed Lunar Laser Ranging

The Apache Point Observatory Lunar Laser-ranging Operation (APOLLO) is a nextgeneration lunar laser ranging (LLR) campaign aimed at order-of-magnitude improvements in tests of gravitational physics via millimeter range precision. We will employ the 3.5 m telescope at the Apache Point Observatory (APO), located in southern New Mexico at an altitude of 2800 m. As a result of the large aperture si...

Gravitomagnetism, Frame-dragging and Lunar Laser Ranging

Gravitomagnetism is a phenomenon predicted by Einstein’s theory of General Relativity, it consists in the interaction generated by a mass current in a way formally similar to magnetism generated by an electric current. A number of experiments have been proposed and carried out to accurately measure the gravitomagnetic interaction. The LAGEOS satellites observations [1], using the GRACE models, ...

Lunar Laser Ranging, Gravitomagnetism and Frame-Dragging

During the past century Einstein’s theory of General Relativity gave rise to an experimental triumph, however, there are still aspects of this theory to be measured or more accurately tested. One of the main challenges in experimental gravitation, together with the direct detection of gravitational waves, is today the accurate measurement of the gravitomagnetic field generated by the angular mo...

Lunar and Planetary Science