Space weather today: From an Earth-centred discipline to a heliosphere-wide field of research

Space weather, i.e. the conditions in space driven by the dynamic solar activity, is a terminology that has been traditionally used to refer to the Sun’s effects on the near-Earth environment. This is because of a rather obvious reason, namely that most of the technological systems susceptible to space weather conditions and all human beings are currently on Earth or in near-Earth space. Hence, space weather research and forecasting efforts have focussed for decades mainly on our own neighbourhood. Nevertheless, in more recent years there has been a paradigm shift, due to which the field of space weather science has been gradually evolving into a heliosphere-wide discipline. This has been motivated by two main factors: (1) a growing interest in human exploration outside the Earth–Luna system, with efforts centred especially on Mars, and (2) an increasing endeavour from the research community to view the solar system as a Sun–heliosphere–planets integrated environment. In this presentation, we will first provide a brief overview of the more “traditional” approach of space weather science to studying the Sun and its transient phenomena—e.g., the structured solar wind, coronal mass ejections, and solar energetic particles. We will then showcase more recent efforts that have been centred on taking advantage of data from missions scattered throughout the solar system to analyse space weather events at multiple points in the heliosphere and their effects on different planetary environments. Finally, we will highlight current and future opportunities for advancing our knowledge of the Sun and space weather-driving phenomena across the heliosphere. Particular emphasis will be given to possible synergies between different subjects of solar system science—i.e. solar, heliospheric, and planetary—and to ideas for the future in terms of multi-disciplinary space missions that can improve our understanding of space weather phenomena from a fundamental physics standpoint and, at the same time, that can expand our knowledge of space weather drivers and effects at other locations than Earth.