Flaming aurora consists of locally intense waves of light passing through the display towards the zenith. The passage of wind through a field of corn is often used to describe flaming. Flaming can herald a subsequent decline in activity, but can precede the formation of a corona. The aurora extends upwards of around 100 km above the Earth's surface and occupies any area of varying atmospheric conditions which produce different colours. The most commonly seen colour is green, associated with arcs, bands and patches especially.
Auroral rays are often green too, but also show a pink or reddish tint near the top.
Aurora seen near dusk or dawn can actually lie in direct sunlight and frequently appears purple as a result. Colour in the aurora is only seen when a display is reasonably bright.