Space weather describes the dynamic conditions in the Earth’s space environment, in the same way as “weather” refers to conditions in Earth’s lower atmosphere. Space weather includes all conditions and events in near-Earth space and in our upper atmosphere that can affect space-borne and ground-based technological systems and, through these, human society. 

We generally consider solar activity to be the main driver of space weather on Earth. The solar wind can be considered an everyday space weather phenomenon, while solar flares, coronal mass ejections, and solar energetic particles can result in more extreme space weather events.