Active Regions

Sunspots are markers of solar activity that come and go in a rather quiet way. However, sunspots typically have associated with them regions of more violent solar activity. We refer generically to these as active regions. Among the phenomena associated with active regions or the corona above them are

Prominences, which are great loops of material above the photosphere.

Solar flares, which are very energetic outbursts from the surface that eject hot matter from the surface.

Coronal mass ejections, which are violent events ejecting hot plasma from the corona at high velocity.

These cause events easily seen from Earth, and in the case of flares and coronal mass ejections they are felt directly on the Earth as bursts in the solar wind.