This book gives a status report on where we stand today in studies of cometary nuclei and their immediate environment. The papers were derived from a Horizon 2020 project called MiARD (Multi-instrument Analysis of Rosetta Data), which was designed to use multiple datasets from the Rosetta mission to comet 67P/Churyumov-Gerasimenko to place further constraints on the properties of the nucleus of the comet and its immediate environment. The individual chapters are the result of a significant effort by leading researchers to establish clear statements on what we know from current cometary data. Based on a workshop held in 2018 at the International Space Sciences Institute, the book focuses on the nucleus itself and the relationship between the surface properties and the observed outgassing. Additionally, it makes a first critical assessment of the Rosetta dataset, establishing what would be an appropriate next step in cometary research. Previously published in Space Science Reviews in the Topical Collection "Comets: Post 67P / Churyumov-Gerasimenko Perspectives"

This collection of scientific papers provides a state-of-the-art look at current knowledge on ocean worlds in our solar system and beyond. It is the result of a collaborative effort by scientists studying both terrestrial and extraterrestrial oceans, and analyzes the emergence of life and its survival on Earth as well as other potentially habitable planets and moons. The papers examine the more remote provinces of our solar system, focusing on the icy moons of the giant planets, like Europa and Titan, as well as bodies like Ceres and putative extrasolar ocean worlds. Their potential for subsurface liquid water oceans are explored, as is as their astrobiological potential. The collection also takes a look at Earth's own oceans, which offer important clues for the investigation of other ocean worlds. In addition, the collection addresses the outstanding key scientific questions and measurements, technologies and laboratory experiments necessary for the exploration of ocean worlds known today. Previously published in Space Science Reviews in the Topical Collection "Ocean Worlds"

From the Earth's atmosphere to the edges of our Universe, the presence of dust is ubiquitous. One of the main challenges in studying dust in these various environments is thus to harmonize the diverse research techniques and results, including in-situ measurement, remote observation, laboratory experiments and modelling, and analysis of returned samples. For the first time in over a decade, this volume accomplishes exactly that, providing an overarching picture of the current state of dust science and research. Where possible, the papers in this volume emphasize the interconnections, similarities, and differences in the field, synthesizing results from several techniques into one cohesive view. Importantly, astrobiological connections have now been considered. The dust hazard, future technology and research, and space mission requirements and scenarios are also addressed. The outcome of this endeavor is an interdisciplinary compendium with a unified perspective on cosmic dust science. Originally published in Space Science Reviews in the Topical Collection "Cosmic Dust from the Laboratory to the Stars"