Why is the evening sky blue?

  • #1
I know the question is generally "Why is the evening sky red/orange?" but actually the evening sky is very rarely red/orange. On most evenings it is blue. Why is it blue? Shouldn't it be red/orangish? Does the location on earth have anything to do with this?
 

Answers and Replies

  • #2
sophiecentaur
Science Advisor
Gold Member
2020 Award
25,384
4,956
It depends on which direction you are looking. Looking towards the setting Sun, you will always get at least a hint of orange / red, which is stronger when the atmosphere is full of scattering particles likedust or water droplets / thin clouds. The blue colour can be seen when you look up or away because there is still comparatively more blue light scattered downwards.
You need to be careful when assessing the colour of the sky (and many other things) because your observational powers are very much affected by context (we are very subjective about these things).
I always use the terms "reddish" and "bluish", to allow for this. This is one of those topics that are frequently discussed and there is a lot of misinformation flying around about it. Don't believe everything you read and check it all against basic theory. :smile:
 

Related Threads on Why is the evening sky blue?

  • Last Post
Replies
23
Views
4K
  • Last Post
Replies
15
Views
4K
  • Last Post
Replies
2
Views
2K
  • Last Post
Replies
7
Views
3K
  • Last Post
Replies
11
Views
3K
  • Last Post
3
Replies
64
Views
11K
  • Last Post
2
Replies
34
Views
5K
  • Last Post
Replies
12
Views
38K
  • Last Post
Replies
18
Views
3K
  • Last Post
Replies
2
Views
1K
Top