Over the last several weeks, you have probably noticed the sun (or moon) looked a little bit more pink or orange than normal. We've seen some beautiful photos sent into WDRB of that very phenomenon. It's caused by smoke particles in the atmosphere, but today we are going to look at why smoke can do this to the sun. 

To understand the smoke, we need to understand the spectrum of visible light. Visible light (things we can see) is made up of the colors of the rainbow, but each color has a slightly different wavelength which you can see in the image below from NASA. Red has a longer wavelength than blue; the distance from one crest of the wave to the next is longer for red than it is for blue. 

When those tiny smoke particles are present in our sky, only longer wavelength colors will make it through to us here on the ground. The shorter wavelengths (like blue and green) are getting blocked by those smoke particles, but the longer wavelengths can travel through or around the particles.

This same principle is why the sky appears blue to our eyes on a clear day. When the visible light from the sun hits our atmosphere, the blue light (with the shortest wavelength) is what gets scattered out by the particles in our atmosphere, so that's what our eyes see. 

The smoke is coming from wildfires in Canada and the western United States. The reason it may feel like we're seeing more smoke this year is because the fire season has started earlier and our jet stream pattern is bringing the smoke right to us. There's a ridge out west and a dip in that jet pattern over the eastern U.S. which drops the smoke off right here in the Midwest. The jet stream will dip more over the next few days, so we should see less smoke by the middle of next week. 

It's also worth noting that this same phenomenon can happen to the moon if it's shining brightly. If you get a picture of a colorful sunset or sunrise, feel free to send it to us! We would love to share some beautiful pictures on our newscasts or online.