What causes an orange glow in the night sky that hides faint stars?
Asked 10/3/2022
7 views
2 answers
0
I photographed the western sky from Sandkrug near Oldenburg, Germany, and noticed a slight orange glow that washes out faint stars even though the sky seemed mostly clear. My exposure was Canon EOS 70D, EF 24-105mm f/4L at 54mm, ISO 1600, f/4, 8 seconds. I’m wondering what is most likely causing this glow: thin clouds, aerosols, or light pollution. There is a small town to the west, but I don’t remember the light pollution looking this strong a few years ago.
Originally by Photography Stack Exchange contributor. Source · Licensed CC BY-SA 4.0
Photography Stack Exchange contributor
3y ago
2 Answers
4
According to Lightpollutionmap.info, it looks like you are in a fairly polluted area, described as Rural/suburban transition (class 4 on the Bortle Dark Sky Scale) where
- light pollution domes are visible in several directions
- the Milky Way well above the horizon is still impressive, but lacks detail
- surroundings are clearly visible, even at a distance
According to your own statements, you said you didn't observe such heavy light pollution some 3 years ago but it might well be that
- some new light sources might have been added during that 3 years span
- some bright light sources were on during the night when you shot the picture you shared (sports venue / stadium lights / etc.)
You could try to observe the sky for several nights and/or at different times and see whether there are nights or times during which the sky gets darker. And if not, you will probably need to find a better (darker) place in your vicinity, if available, depending on what you are trying to achieve.
Originally by user65832. Source · Licensed CC BY-SA 4.0
user65832
3y ago
0
Generated from our catalog & community — verify before relying on it.
The most likely cause is light pollution, not the stars themselves becoming brighter. Based on the location, this appears consistent with a moderately light-polluted area where a visible orange or yellow skyglow can build up near the horizon and hide faint stars.
A few things can make it seem worse than before:
- new or brighter local lighting added in recent years
- temporary bright lights switched on that night, such as sports fields or industrial lighting
- haze, aerosols, or very thin cloud that scatter existing artificial light and amplify the glow
So the glow is probably a combination of nearby artificial lighting plus atmospheric scattering. Thin cloud or haze doesn’t create the glow by itself; it usually makes existing light pollution more obvious.
A practical way to confirm this is to compare the sky on multiple nights and at different times. If the brightness changes significantly, that points to changing local lighting and/or varying haze or cloud cover rather than a permanent astronomical effect.
Recommended products
UniqueBot
AI3y ago
Your Answer
Related Questions
Why is there a reddish glow in the center of my night-sky photo?
How does fog affect sunrise and sunset colors?
Why did an 85mm f/1.2 capture more stars than a 16–35mm f/4?
Is the glow near the horizon in these dark-sky night photos light pollution, airglow, or twilight?
How much better is a 24mm f/1.4 than a 17-40mm f/4L for astrophotography on a Canon 6D?