Airglow
Well, the sky did it again for me! Incredible bands of an atmospheric phenomena known as airglow are readily apparent in this image. In my experience, airglow is stronger as soon as astronomical twilight ends. It is caused by the way sunlight reacts with atmospheric gases, mostly oxygen and nitrogen. There is a fancy $10 word for it….chemiluminescence. Most times it appears as just a green cast to the sky, but occasionally, gravity waves can ripple it into these fantastic bands. I could see these bands with my unaided eyes as faint bluish light. The camera sees them in their true green tint. They can also have a magenta tone to them caused by various elements and altitudes in the atmosphere. It was 35º and quite windy here on the ridge and I was not dressed for it! The next morning my legs were sore from jumping up and down, in an attempt to get warm, for the 30 minutes or so it took to take the 90 images that went into creating this “stacked panorama”.
Nikon D850
Sigma Art 14-24 2.8
ISO 6400, f/2.8, 13 seconds, 14mm
6 image panorama with each image stacked from 10 light and 30 dark images stacked in Starry Landscape Stacker. Merged in PTGui Pro. Processed in Lightroom, Topaz sharpen, and the Ministars action in Photoshop.
https://i.redd.it/m3l8csjkvbjd1.jpeg
1 Comment
That green glow is from oxygen atoms residing about 55 miles above the earth in a thin layer about 5 miles thick. The bands are due to waves passing though the layer and modulating the rate of the photochemical reactions. Those waves sometimes originate from weather events likes fronts and storms and manage to travel all the way into space.