Example images showing three example CMEs in ranked order of subjective complexity increasing from low (left-hand image) through to high (right-hand image). Credit: NASA Heliospheric Imager data courtesy of RAL Space, made available by the UK Solar System

Example images showing three example CMEs in ranked order of subjective complexity increasing from low (left-hand image) through to high (right-hand image). Credit: NASA Heliospheric Imager data courtesy of RAL Space, made available by the UK Solar System Data Centre.