The NASA Dawn mission, launched in 2007, aimed to visit two of the most massive protoplanets of the main asteroid belt: Vesta and Ceres. The aim was to further our understanding of the earliest days of the Solar System, and compare the two bodies to better understand their formation and evolution. This book summarises state-of-the-art results from the mission, and discusses the implications for our understanding not only of the asteroid belt but the entire Solar System. It comprises of three parts: Part 1 provides an overview of the main belt asteroids and provides an introduction to the Dawn mission; Part 2 presents key findings from the mission; and Part 3 discusses how these findings provide insights into the formation and evolution of the Solar System. This is a definitive reference for academic researchers and professionals of planetary science, asteroid science and space exploration.

This volume contains five articles describing the mission and its instruments. The first paper, by the project scientist Richard C. Elphic and his colleagues, describes the mission objectives, the launch vehicle, spacecraft and the mission itself. This is followed by a description of LADEE's Neutral Mass Spectrometer by Paul Mahaffy and company. This paper describes the investigation that directly targets the lunar exosphere, which can also be explored optically in the ultraviolet. In the following article Anthony Colaprete describes LADEE's Ultraviolet and Visible Spectrometer that operated from 230 nm to 810 nm scanning the atmosphere just above the surface. Not only is there atmosphere but there is also dust that putatively can be levitated above the surface, possibly by electric fields on the Moon's surface. Mihaly Horanyi leads this investigation, called the Lunar Dust Experiment, aimed at understanding the purported observations of levitated dust. This experiment was also very successful, but in this case their discovery was not the electrostatic levitation of dust, but that the dust was raised by meteoroid impacts. This is not what had been expected but clearly is the explanation that best fits the data. Originally published in Space Science Reviews, Volume 185, Issue 1-4, 2014.

Atthiswriting the Cassini spacecraft has ?redits engine and successfully inserted itself andits precious cargoof scienti?c instruments into orbit, the ?rst step of its exploration of the Saturnian system. The suspense is not over, however. While excitingimages of therings have been captured, anexotic composition of Phoebe sensedby themapping spectrometer and unexpectedpanoply of magneticwaves andplasma dynamics encountered on the incoming trajectory andinitial orbit, the Huygensprobeisstillonboardandthe?rstclose?ybyofTitanhasnottakenplace. Not until Christmas Day will the probe bereleased.Navigators are still checking theircalculations, worryingaboutknownunknownslikethemassofSaturn'smoons that could cause ever so small a deviation from the planned trajectory of the probe. Theorbiter investigators are also anxious but theyget their taste of Titan earlier, on October 26.Howwell will theydetect the surface? How thickisthe atmosphere? Does Titan haveamagnetic?eld?Isthere lightninginthe atmosphere of Titan? While terrestrial and HubbleSpace Telescope pictures have improvedgreatly over the years, they cannot match the resolution obtainable from orbitabout theplanet, and much of the data issimply unobtainablewithout direct insitu sensing. Volume 1 of this three volume set described the Cassini/Huygens mission, its scienti?c objectives and the Huygens probethat will soon enter theTitan at- sphere. Volume 2 described the insitu investigations on theorbiter. In this, the third and ?nal volume of the compendium, we describethe remote sensing inv- tigations: radioscience, radar, visibleandinfrared spectroscopy, thermalinfrared studies, ultraviolet spectroscopy and visible imagery.

The Magnetosheath and Magnetotail of Venus.- The Structure of the Venus Ionosphere.- Ion Dynamics in the Venus Ionosphere.- Magnetic Fields in the Ionosphere of Venus.- Plasma Waves at Venus.- Venus Lightning.- The Structure, Luminosity and Dynamics of the Venus Atmosphere.

In December 2014, Hayabusa2 started its journey to 162173 Ryugu, a C-type asteroid likely to be primordial, thereby making this a voyage in both space and time. Hayabusa2 will begin its observations upon arrival at Ryugu in 2018. It will survey the asteroid's surface features, touch down on the asteroid, form an artificial crater by shooting an impactor, and collect sample materials both on and under the surface. In 2020, Hayabusa2 will return to Earth and release a re-entry capsule carrying material from Ryugu. This book contains papers describing the scientific objectives and instrumentation on Hayabusa2 and its landing package, MASCOT. The methods and developments presented in these papers have challenged the state-of-the-art of planetary exploration. This book is indispensable to understanding the results that Hayabusa2 will bring through its in situ and sample return exploration. Originally published in Space Science Reviews, Volume 208, Issue 1-4, July 2017

Comets consist of the most primitive, i.e. unprocessed, material in the solar system. To understand the earliest epoch of solar system formation, we must investigate the nature of this material. Much of what we know of comets presently comes from remote sensing using Earth-based telescopes, plus a few brief flybys that have added only a few hours of in-situ observation. The Rosetta mission is poised to make a dramatic advance in our understanding of comets by matching trajectories with comet 67P/Churyumov-Gerasimenko, orbiting it, and setting a lander on its surface. This volume describes the scientific objectives of the mission, the expected cometary environment, and the instruments that will probe the comet.