This book depicts a vivid and vibrant image of modern Main Belt asteroid science. In the last decade, thanks to the exploration by the NASA Dawn mission and the advent of high-resolution Earth-bound observations, we have entered a renaissance of Main Belt asteroid science. Formation theories, dynamical models, meteorite geochemical data, remote and in-situ observations synergistically show asteroids are leftover building blocks of planetary formation and tracers of important evolutionary processes (e.g., collisions, orbital migration) that have shaped the evolution of the early Solar System. Planned missions such as NASA’s Lucy and Psyche (scheduled to launch in 2021 and 2022) will surely provide additional colorful strokes to our ever-evolving portrait of the Main Belt.

A search for volcanic and plutonic features on Vesta was an important driver for a geomorphological examination of the asteroid. Another goal was to determine if the asteroid was a protoplanet, one of the remnants of the material that formed the Solar System. Therefore, NASA’s Dawn spacecraft collected imaging, spectroscopic, and elemental abundance data, which were utilized to examine the asteroid’s surface. A digital terrain model was created and the asteroid’s various geomorphic features were analyzed. Large scale features include the Rheasilvia and Veneneia impact basins, the Divalia Fossae and Saturnalia Fossae trough sets, and the Vestalia Terra plateau. Small scale features include deposits of dark material, pitted terrain, pit crater chains, mass-wasting deposits, and impact craters. While these geomorphic analyses revealed no evidence of volcanism, evidence of magmatic activity on Vesta was identified. In addition, analysis of Vesta’s geomorphology suggests that it is not only a protoplanet, but also an intermediate body between asteroids and planets.

Carbon, central to astrobiology, shaped the development of the dwarf planet Ceres, a water-rich protoplanet explored by NASA’s Dawn mission. As a candidate ocean world, Ceres has the potential to provide new insights into prebiotic chemistry and habitability. This chapter reviews observations of carbon and organic matter on Ceres by Dawn and Earth-based telescopes. The observations are placed in context with astrophysical processes that produced organic matter in nebular materials from which Ceres grew. We consider mechanisms for destruction and synthesis of organic matter with changing hydrothermal conditions within Ceres’ interior. This is supported by studies of Ceres’ closest meteorite analogs, the aqueously altered carbonaceous chondrites, and halite crystals containing organic matter that may have formed within Ceres. Ultraviolet-, infrared-, and nuclear-spectroscopy show that Ceres’ surface contains a mixture of carbonates and organic matter in concentrations higher than the meteorite analogs. Ceres carbon-rich surface results from a combination of impacts and complex processes that occurred within Ceres’ interior, including low-temperature aqueous alteration, ice-rock fractionation, and modification of the accreted carbon species during serpentinization. This chapter reviews the current state of knowledge about carbon on Ceres, including sources of carbon and organics, parent body processes, remote sensing observations, and their interpretation.

Climate change: between democracy and expertise?

Climate change represents one of society's most challenging environmental concerns and has been a major factor in changes in the way that environmental policies are debated and informed. Climate change policy faces at least three major challenges: (1) what is known – or not known – about climate change, in particular regarding the relative importance of anthropogenic factors; (2) what can and should be done; and (3) who should do something about it?

Since the 1992 Rio Earth Summit, these challenges have been addressed in several ways: (a) by increasing research and international sharing and integration of expertise on climate change (e.g., the Intergovernmental Panel on Climate Change); (b) by developing international agreements on issues such as the reduction of carbon dioxide emissions; and (c) by promoting national/local strategies to fulfil international agreements (e.g., Local Agenda 21 – community defined strategies for sustainable development arising from the first “Earth Summit” held in Rio in 1992). These challenges all include policy and scientific aspects but also raise questions over the interpretation of Local Agenda 21 (Tuxworth 1996; Selman and Parker 1997; Voisey et al. 1996; Young 1996; Young 1997). How local is “local”? What kind of “agenda” is “Agenda 21”? Whose “agenda” is it? Answers to these questions vary according to the perspectives and purposes of those asking the questions in the first place.