I'm skeptical that we ever see ozone blue. Twilight is when the sky is lit by indirect light coming from parts of the sky in the direction of the Sun, mostly or completely over the horizon.So every moment of twilight involves some combination of direct and indirect sunlight, it seems. At the latest/earliest moments of astronomical twilight, there is a very minimal amount of direct sunlight arrivng at a very steep angle -- and the direct sunlight hits the upper atmosphere, into the ozone layer, takes on the characteristics of ozone blue, and "bounces down" as indirect light?The lower blue part of the Belt is just the twilight sky rising (or setting). In the evening I sometimes call it "nightrise". So yeah, it is only lit indirectly, by light that has scattered from air still lit by the Sun directly.
("bounces down" would be a metaphor I would be able to grasp)
Statistics: Posted by Chris Peterson — Sat May 18, 2024 5:07 pm — Replies 38 — Views 2713