Comments on: Violet Sky

By: sjastro

sjastro — Sat, 28 Jan 2017 00:42:11 +0000

Your point is taken that ozone has a blue colour.
Given that ozone mostly exists in the stratosphere at average concentrations of around 0.6 ppm, the concentration is way too low to contribute to the sky colour.

The blue colour of liquid oxygen is due to absorption of photons at 650nm which excite the oxygen molecular bonds.
Light in the 650nnm range is deep red in colour, absorption of red light gives liquid oxygen its blue colour.

By: Aldor Ericsson

Aldor Ericsson — Fri, 27 Jan 2017 23:53:28 +0000

Even so, ozone content in our atmosphere is extremely low, and its contribution into overall color of the sky is negligible.

By: Oskar Axelsson

Oskar Axelsson — Wed, 25 Jan 2017 07:19:51 +0000

Ozone is definitely blue. It only looks colorless at low conc. It is said to be the cause of the blue tinge you see in liquid oxygen. There aŕe plenty of ozone pics available on the internet.

By: sjastro

sjastro — Fri, 20 Jan 2017 22:10:46 +0000

I don’t think so.

Ozone is a colourless gas but is produced by processes such as a corona discharge which has a characteristic blue colour.
The corona discharge ionizes gas producing electrons and positive ions.
These electrons can be recaptured by the positive ions emitting photons in the process resulting in the colour.

By: Oskar Axelsson

Oskar Axelsson — Tue, 17 Jan 2017 19:03:10 +0000

I have heard/read somewhere that ozone, which is blue, contributes quite a lot to the blue color of the sky. I have no recollection of exactly how much though.