Did you know the moon can appear bright red, almost like a scene from a science fiction movie? It happened recently, and I managed to capture a vivid red moon caused by wildfire smoke. It’s a stunning visual reminder of how much our atmosphere influences what we see, and it connects directly to the larger conversations we need to have about climate change and its effects on our environment.
Normally, the moon looks the way it does because of how sunlight interacts with Earth’s atmosphere. During a typical full moon, sunlight travels through the atmosphere and gets scattered. Blue light, with its shorter wavelengths, scatters more easily than red light, which is why the sky appears blue during the day. When we look at the moon, we’re seeing sunlight that has been reflected off its surface. Most of this light travels straight to our eyes, giving us the familiar whitish or yellowish hue.
But then came the smoke. Large wildfires, especially those producing a lot of fine particulate matter, can dramatically change this. These tiny particles, often smaller than the wavelength of visible light, are incredibly effective at scattering sunlight. When smoke fills the air, it acts like a filter. The smaller, bluer wavelengths of light get scattered away much more efficiently by the smoke particles. This leaves the longer, redder wavelengths to pass through more directly. So, when moonlight travels through a smoke-filled atmosphere, it’s this remaining red light that reaches our eyes, painting the moon in an eerie, beautiful crimson.
Think of it like this: the smoke particles are scattering away the blues and greens, letting the reds and oranges make it through. It’s the same principle that causes vibrant sunrises and sunsets, where sunlight has to travel through more of the atmosphere, and the blues are scattered away, leaving the fiery colors behind.
This phenomenon isn’t just a beautiful, albeit concerning, spectacle. It’s a direct illustration of how atmospheric conditions, often exacerbated by events like wildfires (which are becoming more frequent and intense due to climate change), can alter our perception of the natural world. The quality of the air we breathe, the visibility we experience, and even the colors of celestial bodies are all influenced by the composition of our atmosphere.
For those of us who study climate and atmospheric science, these events are powerful, visible indicators of broader trends. They underscore the interconnectedness of our planet’s systems and the tangible ways that environmental changes can impact our daily lives, even in something as seemingly distant as the appearance of the moon. It’s a reminder that the health of our planet directly affects our experience of it.