Proton Arc Vancouver BC
The name may be misleading as it is not entirely clear as to what this arc is properly called. It is not fully understood either and there has been some discussion to call it STEVE [ an acronym meaning “Strong Thermal Emission Velocity Enhancement”]
We are still learning about this unique phenomenon...
It occurs with the showing of the Aurora Borealis [seen off to the right in this image].
On the far right is the 'down arrow'- click on that to open 'original' size... click 'open' on original size and then hit F11 on keyboard for full screen effect...best viewed in the dark.