We present here the new INPOP lunar ephemeris, INPOP17a. This ephemeris is obtained through the numerical integration of the equations of motion and of rotation of the Moon, fitted over 48 years of Lunar Laser Ranging (LLR) data. We also include the 2 years of infrared (IR) LLR data acquired at the Grasse station between 2015 and 2017. Tests of the universality of free fall are performed. We find no violation of the principle of equivalence at the 10 −14 level. A new interpretation in the frame of dilaton theories is also proposed.

Lunar laser ranging (LLR) data and Apollo seismic data analyses, revealed independent evidence for the presence of a fluid lunar core. However, the size of the lunar fluid core remained uncertain by ±55 km (encompassing two contrasting 2011 Apollo seismic data analyses). Here we show that a new description of the lunar interior's dynamical model provides a determination of the radius and geometry of the lunar core‐mantle boundary (CMB) from the LLR observations. We compare the present‐day lunar core oblateness obtained from LLR analysis with the expected hydrostatic model values, over a range of previously expected CMB radii. The findings suggest a core oblateness (fc=(2.2±0.6)×10−4) that satisfies the assumption of hydrostatic equilibrium over a tight range of lunar CMB radii ( RCMB=381±12 km). Our estimates of a presently relaxed lunar CMB translates to a core mass fraction in the range of 1.59–1.77% with a present‐day free core nutation within (367±100) years.