Hi Maggie

the term 'solar storm' is a kind of overall description for many different things happening on the sun, but each of these things has been known about and described for a different length of time. For example, one part of a solar storm is a coronal mass ejection, and we have been using that term since the 1970s. On the other hand the term 'solar flare' has been used at least since 1943, along with the term 'magnetic storm' to describe what happens nearer the Earth.