|Greenland Subsun ~ Imaged by Stefan Kuna. ©Stefan Kuna, shown with permission.
The subsun is a direct reflection of the sun from millions of plate shaped ice crystals in a thin lower cloud layer.
It followed the aircraft as it passed over SW Greenland . Below are glaciers flowing from the Greenland ice cap. The cap is second only to Antarctica in size and in places is up to 3km (1.8 mile) thick.