Solar Flares

What Carrington witnessed that afternoon were solar flares.  Solar flares are intense bursts of electromagnetic radiation which usually occur around sun spots. 

Coronal mass ejection

Frequently associated with solar flares, and what happened in the Carrington event, are coronal mass ejections.  A CME releases a huge amount of electrons, protons  helium ions and less frequently heavier ions. Both solar flares and CME’s are thought to be caused by ‘magnetic reconection’ occuring near the sun’s surface.

Magnetic reconnection

The sun posseses a powerful magnetic field.  Since the polar and equitorial regions of the sun rotate asymetrically, these field lines are constantly being warped and rearranged and can cause concentraded portions of the field, causing sunspots.  Sunspots usually occur in pairs, manifesting at the poles of concentrated portion of the field which restrict movement in a small area, cooling the area and causing the apparent sunspot. These field lines can connect with one another and form new ones, leaving a helix of magnetic field unconnected to the rest. The liberated electric field may then rapidly expend outward, carrying ionized plasma along with it resulting in a flare or CEM. .

Carrington’s sketch of the flare