Wildfire Smoke Reddens Sun, Dims Stars

 

The sun and sky were "on fire" last night, July 2, colored by forest fire smoke. Bob King

The past few days and nights you may have noticed how much less blue the sky appears even with the sun shining. Today (July3) in northern Minnesota, the meteorologists will tell you it's clear and sunny, but the sky is actually gray. As for the sun, even 3 hours past sunrise it's still tinged pale orange.

This satellite view on June 30, 2021 shows a plume of smoke moving south out of Canada into Minnesota. Currently, the Midwest and far West are under smoky skies. NOAA

These are symptoms of smoke from wildfires across the western and southwestern U.S. as well as Canada. Today, July 3, smoke plumes loom over the Midwest and far West. Most of the smoke lies at high elevations so you can't smell it. But occasionally, winds bring it closer to the ground, and the air smells like a campfire. Too much of it can pose a health hazard.

Sunspot region 2835 shows through the haze just before sunset on July 2nd. This group is currently big enough to see with the naked eye through a SAFE solar filter. Bob King

On the plus side, smoke attenuates the light of sun to provide a bit of relief from the heat. It also turns the sun into an atomic fireball around sunrise and sunset. Then again, smoke dims the stars at night. Last night, while the Milky Way was still visible from my home, stars within 25° of the horizon were faint and difficult to see. 

Hopefully, the haze will clear soon, but it's become a fact of life for much of the U.S. for at least the past 10 years. 



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