Hint of Pink

The majority of auroral displays are predominantly green for two reasons,
the first of which is that the human eye detects green more readily than other colours.
This is why photographic images of the Northern Lights will often show colours
that were not visible at the time to the naked eye.
Very occasionally, you can see yellow and pink in an Auroral display
which are associated with only high solar activity as they are simply a mixture of red with green or blue.