The overlay to the right shows green where the electron aurora dominates, red where the proton aurora dominates, and yellow where both are comparable.
Red colors indicate the highest intensity of incoming particles, blue represents the lowest.
We are looking from the sun towards the Earth, viewing the cloud beyond the Earth on the night side. Image of the plasmasphere near the Earth obtained with the EUV instrument. Ultraviolet image of sunlight scattered from the Earth's extended atmosphere of helium using the Extreme Ultraviolet Imager instrument. This image shows that the ionized helium atmosphere extends to about 2 - 3 times the size of the Earth. Irregularities at the fringe of the image, such as the upper left, indicate magnetic storm activity.