Starship Asterisk*

neufer wrote: ↑Sun Feb 03, 2019 3:52 pm

Chris Peterson wrote: ↑Sun Feb 03, 2019 2:32 pm

E Fish wrote: ↑Sun Feb 03, 2019 2:29 pm
Is airglow ever really that dramatic? It seems like it would require a long exposure or at least some processing to have it show up so dramatically, especially with all the detail showing up with the Milky Way.

Airglow, like the Milky Way, doesn't show color to the human eye. All images like this take advantage of the ability of a camera to show color and contrast that we cannot see with our eye alone. (Which is kind of the point!)

https://www.atoptics.co.uk/highsky/airglow1.htm wrote:
<<To see [airglow one] needs long dark adaptation. Eventually, when stars are almost blinding and the Milky Way is a bright convolved mass, the sky itself will be seen to be luminous and a hand held towards the heavens will be a black silhouette.

It is strongly coloured yet it is without colour to our unaided eyes because its light is below their threshold of colour perception. From orbit it is a green bubble enclosing the world.

Look carefully and banded or uneven structure changing slowly over minutes might be visible. The bands can appear to cross the sky and converge towards two opposite points on the horizon in the same way that crepuscular and anticrepuscular rays do. The reason is the same, the glowing bands are parallel and perspective effects makes them appear to converge.>>

Chris Peterson wrote: ↑Sun Feb 03, 2019 2:32 pm

E Fish wrote: ↑Sun Feb 03, 2019 2:29 pm
Is airglow ever really that dramatic? It seems like it would require a long exposure or at least some processing to have it show up so dramatically, especially with all the detail showing up with the Milky Way.

Airglow, like the Milky Way, doesn't show color to the human eye. All images like this take advantage of the ability of a camera to show color and contrast that we cannot see with our eye alone. (Which is kind of the point!)

https://www.atoptics.co.uk/highsky/airglow1.htm wrote:
<<To see [airglow one] needs long dark adaptation. Eventually, when stars are almost blinding and the Milky Way is a bright convolved mass, the sky itself will be seen to be luminous and a hand held towards the heavens will be a black silhouette.

It is strongly coloured yet it is without colour to our unaided eyes because its light is below their threshold of colour perception. From orbit it is a green bubble enclosing the world.

Look carefully and banded or uneven structure changing slowly over minutes might be visible. The bands can appear to cross the sky and converge towards two opposite points on the horizon in the same way that crepuscular and anticrepuscular rays do. The reason is the same, the glowing bands are parallel and perspective effects makes them appear to converge.>>

E Fish wrote: ↑Sun Feb 03, 2019 2:29 pm Is airglow ever really that dramatic? It seems like it would require a long exposure or at least some processing to have it show up so dramatically, especially with all the detail showing up with the Milky Way.

JohnD wrote: ↑Sun Feb 03, 2019 9:58 am Wouldn't this view have looked more like this?
The arch of the Milky Way stretches a lot further around the horizon.

John