To appear in: Mercury - The View after MESSENGER, S. C. Solomon, B. J. Anderson, L. R. Nittler (editors), CUP MERCURY'S INTERNAL STRUCTURE Jean-Luc Margot,1, 2 Steven A. Hauck, II,3 Erwan Mazarico,4 Sebastiano Padovan,5 and Stanton J. Peale6, ∗ 1Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles, CA 90095, USA 2Department of Physics and Astronomy, University of California, Los Angeles, CA 90095, USA 3Department of Earth, Environmental, and Planetary Sciences, Case Western Reserve University, Cleveland, OH 44106, USA 4Planetary Geodynamics Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA 5German Aerospace Center, Institute of Planetary Research, Berlin, 12489, Germany 6Department of Physics, University of California, Santa Barbara, CA 93106, USA (Received July 28, 2016; Revised April 13, 2017) ABSTRACT We describe the current state of knowledge about Mercury's interior structure. We review the available observational constraints, including mass, size, density, gravity field, spin state, composition, and tidal response. These data enable the construction of models that represent the distribution of mass inside Mercury. In particular, we infer radial profiles of the pressure, density, and gravity in the core, mantle, and crust. We also examine Mercury's rotational dynamics and the influence of an inner core on the spin state and the determination of the moment of inertia. Finally, we discuss the wide-ranging implications of Mercury's internal structure on its thermal evolution, surface geology, capture in a unique spin-orbit resonance, and magnetic field generation. Keywords: Mercury, interior structure, spin state, gravity field, tidal response Corresponding author: Jean-Luc Margot
[email protected] ∗ Deceased 14 May 2015 2 Margot et al.