From a science-fiction development perspective I am looking for some plausible answer for the following:

What conditions (the more permanent, the better) would make for a bronze sky?

All the better, could we be currently creating those conditions?

For instance, the sky is typically blue based on the current conditions of our atmosphere and light. What conditions would make orange/brown appearance more prominent? Dull, lacking life.

Technically, a reddish-orange color would be acceptable too.

Either the sun itself or degenerate (or even natural) conditions can contribute to this.

  • $\begingroup$ Related: worldbuilding.stackexchange.com/questions/29956/…. $\endgroup$
    – HDE 226868
    Commented Dec 17, 2015 at 0:59
  • 1
    $\begingroup$ After the Mt. Pinotubo volcanic eruption, I watched the sunsets off the north west coast of Australia. Pretty impressive, especially with a beer in hand. The sky at sunset had a bronzish colour to it, although there were many other colours as well. $\endgroup$
    – Smoj
    Commented Dec 17, 2015 at 3:39
  • $\begingroup$ Possibly iron oxide dust somehow ejected into the atmosphere in massive levels might colour the sky an orange red. The Pilbara region of Western Australia is almost entirely composed of iron oxide. Large parts of it, anyway. $\endgroup$
    – Smoj
    Commented Dec 17, 2015 at 3:42
  • $\begingroup$ Another thing to look at might be Mars. With a denser atmosphere, would Mars have a darker, more red coloured sky? $\endgroup$
    – Smoj
    Commented Dec 17, 2015 at 3:43
  • $\begingroup$ @Smoj interesting you mention iron oxide. I'm spinning off of a scripture in the bible: Your sky will be bronze and your earth iron. Your answer implies one would cause the other. :D $\endgroup$
    – Pipsqweek
    Commented Dec 17, 2015 at 4:32

3 Answers 3


Turns out this is happening- right now, on this planet, in reality.

All you need is some smog. This photo from Beijing last year looks rather bronze-ish to orange-ish I think.

enter image description here (image source: International Science Times)

  • $\begingroup$ Interesting article about how banning cars and closing some factories caused the air to improve pretty fast. The sky looks pretty grey during the day. I think that picture is a sunset shot. Looks like something out of hell... $\endgroup$
    – AndyD273
    Commented Dec 17, 2015 at 16:38

Dust/fines in the atmosphere would be able to do it.
Mars has a reddish sky because of this.
The reason is that the dust particles in the atmosphere absorb sunlight in the 0.4-0.6 µm range, giving it a red tint.

Could we do it? It would be harder on Earth, as the moisture in the air would collect around the dust and come down as rain.
You might get it to work for a little while, especially if it was super fine dust (fines) up really really high, but our weather would clear it up again before to long.


The simplest way to achieve this is just have the planet in orbit around a cooler (redder) star than our sun. You can adjust the orbit to still be in the habitable band and the incoming red light would color the whole sky that way.

The next best solution would probably to have much less water and a lot of iron oxide on the planet. Vast arid areas would cause dust to be picked up in the wind and colour the entire sky. This would clear sometimes and at other times be a full-on sandstorm.

  • $\begingroup$ A "red" star is one that has its illumination peak in the red. It would still look white to us. To get red sunlight you would need a brown dwarf. $\endgroup$
    – Mary
    Commented Apr 12, 2023 at 2:36

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .