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The activity of the Sun alternates between a solar minimum and a solar maximum, the former corresponding to a period of "quieter" status of the heliosphere. During solar minimum, it is in principle more straightforward to follow eruptive events and solar wind structures from their birth at the Sun throughout their interplanetary journey. In this paper, we report analysis of the origin, evolution, and heliospheric impact of a series of solar transient events that took place during the second half of August 2018, that is, in the midst of the late declining phase of Solar Cycle 24. In particular, we focus on two successive coronal mass ejections (CMEs) and a following high‐speed stream (HSS) on their way toward Earth and Mars. We find that the first CME impacted both planets, whilst the second caused a strong magnetic storm at Earth and went on to miss Mars, which nevertheless experienced space weather effects from the stream interacting region preceding the HSS. Analysis of remote‐sensing and in‐situ data supported by heliospheric modeling suggests that CME–HSS interaction resulted in the second CME rotating and deflecting in interplanetary space, highlighting that accurately reproducing the ambient solar wind is crucial even during "simpler" solar minimum periods. Lastly, we discuss the upstream solar wind conditions and transient structures responsible for driving space weather effects at Earth and Mars. Plain Language Summary: The Sun is characterized by a 11‐year periodicity of its levels of activity, resulting in a solar minimum and a solar maximum alternating approximately every 5.5 years. During solar minimum, the Sun and its whole environment are in their simplest configuration, and eruptive events are significantly less frequent. It follows that periods of lower activity are generally considered optimal for tracking solar phenomena from their origin at the Sun throughout their journey in interplanetary space. In this paper, we analyze a series of solar eruptions that took place during the second half of August 2018 and follow them until their arrival at Earth and Mars, taking into account their associated effects on the two planets. We find that, even during solar minimum, the large‐scale structure of the solar and interplanetary environment can have more or less dramatic impacts on the evolution of eruptions as they travel away from the Sun. Additionally, we suggest that the same event can cause diverse levels of disturbances at different planets, depending on the particular structure and properties of the impacting solar wind. Key Points: We analyze the eruption and propagation of two coronal mass ejections (CMEs) from the Sun up to Earth and Mars during August 2018Both CMEs were observed at Earth, but the second missed Mars, possibly due to interaction with a following high‐speed solar wind streamThe sequence of events observed resulted in a strong magnetic storm at Earth, but only moderate disturbances at Mars [ABSTRACT FROM AUTHOR]

The Wind spacecraft, launched on November 1, 1994, is a critical element in NASA's Heliophysics System Observatory (HSO)—a fleet of spacecraft created to understand the dynamics of the Sun‐Earth system. The combination of its longevity (>25 years in service), its diverse complement of instrumentation, and high resolution and accurate measurements has led to it becoming the "standard candle" of solar wind measurements. Wind has over 55 selectable public data products with over ∼1,100 total data variables (including OMNI data products) on SPDF/CDAWeb alone. These data have led to paradigm shifting results in studies of statistical solar wind trends, magnetic reconnection, large‐scale solar wind structures, kinetic physics, electromagnetic turbulence, the Van Allen radiation belts, coronal mass ejection topology, interplanetary and interstellar dust, the lunar wake, solar radio bursts, solar energetic particles, and extreme astrophysical phenomena such as gamma‐ray bursts. This review introduces the mission and instrument suites then discusses examples of the contributions by Wind to these scientific topics that emphasize its importance to both the fields of heliophysics and astrophysics. Plain Language Summary: The Wind spacecraft is a south ecliptic pointed spinning spacecraft that was launched on November 1, 1994. It is equipped with an array of instrument suites that measure electric and magnetic fields, electrons from thermal to relativistic energies, protons and alpha‐particles from thermal to suprathermal energies, and energetic ions from hydrogen to trans‐iron elements. Wind can also observe remote sources of electromagnetic radiation in the radio and gamma‐ray frequency ranges. This diverse array of instrumentation and numerous near‐Earth environments explored has allowed researchers to examine such a broad range of research topics including astrophysics, turbulence, kinetic physics, magnetic reconnection, interplanetary and interstellar dust, transient solar phenomena, and the radiation belts. Examples of the contributions of Wind to the fields of heliophysics and astrophysics are reviewed. Key Points: Wind has made seminal advances to the fields of astrophysics, turbulence, kinetic physics, magnetic reconnection, and the radiation beltsWind pioneered the study of the source and evolution of solar radio emissions below 15 MHzWind revolutionized our understanding of coronal mass ejections, their internal magnetic structure, and evolution [ABSTRACT FROM AUTHOR]

We present here a brief summary of the rich heritage of observational and theoretical research leading to the development of our current understanding of the initiation, structure, and evolution of Coronal Mass Ejections. [ABSTRACT FROM AUTHOR]

The heliospheric counterparts of coronal mass ejections (CMEs) at the Sun, interplanetary coronal mass ejections (ICMEs), can be identified in situ based on a number of magnetic field, plasma, compositional and energetic particle signatures as well as combinations thereof. We summarize these signatures and their implications for understanding the nature of these structures and the physical properties of coronal mass ejections. We conclude that our understanding of ICMEs is far from complete and formulate several challenges that, if addressed, would substantially improve our knowledge of the relationship between CMEs at the Sun and in the heliosphere. [ABSTRACT FROM AUTHOR]