They involve faster ejections of material than eruptive prominences, and reach velocities of 20 to 2000 kilometers per second.

Illustrations: Ultraviolet image of the Sun, showing a huge eruptive prominence, (C) SOHO/EIT consortium.

Other forms of solar activity frequently associcated with coronal mass ejections are eruptive prominences, coronal dimming, coronal waves and Moreton waves, also called solar tsunami.

Three aspects of observing the Sun through a Hydrogen-alpha filter are described with examples from the author's sketches; Quiet Prominences, an Eruptive Prominence and Promince motion by tuning the H-alpha filter for different Doppler Shifts.