“One of the visible signs of the current wildfire smoke settling over Trail and much of B.C. is how it affects the look of the moon and sun,” David Dudeck explains, referring to his photos of the orange rising moon and the moon early Tuesday, pale and muted as it set.
Both images are from the vantage point of Dudeck’s yard.
Colours of the moon can change due to the presence of smoke from wildfires in the atmosphere.
Here’s why this happens:
Light scattering: Smoke particles in the atmosphere scatter light. This phenomenon is called Rayleigh scattering. When there are more particles (such as those from wildfire smoke), this scattering affects shorter wavelengths of light (blue and green) more than longer wavelengths (red and yellow). This can make the moon appear red, orange, or yellow.
Particle size and density: The specific colour seen can vary depending on the size and density of the smoke particles. Smaller particles scatter blue light, making the moon appear redder, while larger particles can scatter more light overall, creating a dimmer, yellower appearance.
Angle of observation: The colour can also change depending on the angle of the moon in the sky. When the moon is closer to the horizon, its light passes through a thicker layer of the Earth's atmosphere, encountering more particles and causing more scattering. This is similar to why sunsets and sunrises often appear red or orange.
Absorption of light: Some smoke particles can also absorb certain wavelengths of light. For example, carbon particles from soot can absorb blue and green light, which can enhance the red and orange hues seen in the moon.
Overall, the combination of these factors results in the moon taking on different colours when there is a significant amount of smoke in the atmosphere from wildfires.
