Preface; Citations; Acknowledgements; Contents; Chapter 1: A Pale Pink Dot; 1.1 Elusive Planet; 1.2 Seeing Mercury; 1.3 Orbit and Transits; 1.4 Mapping by Telescope, and Mercuryś Rotation; 1.4.1 Early Telescopic Observations; 1.4.2 Schiaparelli and ``Synchronous Rotation;́́ 1.4.3 Antoniadiś Map, and Later; 1.4.4 Not Synchronous After All; 1.4.5 A Day Twice as Long as a Year; 1.4.6 Hot Poles and Warm Poles; 1.4.7 An Explanation for 3:2 Spin:Orbit Coupling; 1.5 Mercuryś Size, Mass and Density; Chapter 2: The Mariner 10 Era of Mercury Science; 2.1 Introduction

2.2 Three Flybys for the Price of One2.2.1 The Trajectory; 2.2.2 Limitations; 2.3 Mariner 10ś Instruments; 2.3.1 Television Science; 2.3.2 Infrared Radiometry; 2.3.3 Ultraviolet Spectroscopy; 2.3.4 Celestial Mechanics and Radio Science; 2.3.5 Magnetic Field; 2.3.6 Plasma Science; 2.3.7 Charged Particles; 2.4 Mapping a New Planet; 2.4.1 Quadrangles; 2.4.2 Naming Features; 2.5 What Mariner 10 Found; 2.5.1 Surface Characteristics; 2.5.2 Mercury Timescale and Stratigraphy; 2.5.3 The Magnetic Field; 2.5.4 The Interior; Box 2.1. Terminology for Planetary Interiors; 2.5.5 Surface Composition

2.5.6 Space Weathering2.5.7 The Exosphere; 2.5.8 Polar Ice?; 2.6 The Conundrum of Mercuryś Origin; Chapter 3: High Time for Another Mission?; 3.1 Introduction; 3.2 Back to Mercury; 3.3 MESSENGER; 3.3.1 The Trajectory and Orbit; 3.3.1.1 The Cruise and Flybys; 3.3.1.2 Orbiting Mercury; 3.3.2 The Spacecraft; 3.3.2.1 Thrusters; 3.3.2.2 Thermal Design; 3.3.2.3 Communications and Data Storage; 3.3.3 The Payload; 3.3.3.1 Mercury Dual Imaging System, MDIS; 3.3.3.2 Gamma-Ray and Neutron Spectrometer, GRNS; 3.3.3.3 X-Ray Spectrometer Spectrometer, XRS; 3.3.3.4 Magnetometer, MAG

3.3.3.5 Mercury Laser Altimeter, MLA3.3.3.6 Mercury Atmospheric and Surface Composition Spectrometer, MASCS; 3.3.3.7 Energetic Particle and Plasma Spectrometer, EPPS; 3.3.3.8 Radio Science, RS; 3.4 BepiColombo; 3.4.1 The Trajectory and Orbit; 3.4.1.1 The Cruise and Flybys; 3.4.1.2 Orbiting Mercury; 3.4.2 The Spacecraft; 3.4.2.1 Transfer Module; 3.4.2.2 MPO; 3.4.2.3 MMO; 3.4.3 The Payload; 3.4.3.1 BepiColombo Laser Altimeter, BELA (MPO); 3.4.3.2 Italian Spring Accelerometer, ISA (MPO); 3.4.3.3 Mercury Polar Orbiter Magnetometer, MPO/MAG (MERMAG)

3.4.3.4 Mercury Thermal Infrared Spectrometer, MERTIS (MPO)3.4.3.5 Mercury Gamma-ray Neutron Spectrometer, MGNS (MPO); 3.4.3.6 Mercury Imaging X-ray Spectrometer, MIXS (MPO); 3.4.3.7 Mercury Orbiter Radio Science Experiment, MORE (MPO); 3.4.3.8 Probing the Hermean Exosphere by Ultraviolet Spectroscopy, PHEBUS (MPO); 3.4.3.9 Search for Exospheric Refilling and Emitted Natural Abundances, SERENA (MPO); 3.4.3.10 Spectrometer and Imagers for MPO BepiColombo Integrated Observatory System, SIMBIO-SYS; 3.4.3.11 Solar Intensity X-ray and Particle Spectrometer, SIXS (MPO)