I've posted quite a few pictures from NASA's Earth-observing Terra satellite over the past few months, some of them showing devastating natural disasters. But I never thought I'd post one that shows something so close to home. This image was taken yesterday, September 6th, at about noon Mountain time:

That shows the plume of smoke from the Fourmile Canyon fire that I wrote about yesterday. The image is roughly 300 km (190 miles) across. The vertical dividing line is the actual edge of the Rocky Mountains; to the left (west) are the mountains, and to the right (east) is the start of the Great Plains stretching most of the way across the US. The green smudge just to the south of the plume is Denver, and the smoke goes directly over Boulder... and my house. The fire is still going as I write this, but the winds have shifted and there is no longer a plume overhead. It smells like ash outside though, and the foothills -- usually visible a few kilometers to the west from my house -- are almost totally hidden.

I appreciate all the notes and tweets I've gotten, but we're safe here. The fire is pretty far west of us, though we could see it poking over the first set of foothills last night. Creepy. My brother-in-law has taken some amazing pictures of the fire from his house, located even farther to the east than where I am. This one shows the tops of the fires. I'll add that the sunset yesterday was desperately beautiful:

The smoke is made up of tiny particles of soot and ash. When blue light hits them, it scatters like a pinball off a bumper. So when you look to the Sun through the smoke, all the blue light has bounced off in a different direction, leaving only the redder light able to make its way straight to your eye. This happens on a lesser scale every night with particles in the air, making sunsets red. But this fire has really strengthened the effect, and the Sun went through myriad shades of red on its way down past the mountains last night. It was astonishing. Making it even more wrenching was knowing what was a causing it, and that there were people in the middle of all that smoke trying to put the fires out. So far, there are still no reported injuries, though many homes have been destroyed and over 1000 people have been evacuated from the area.

My thanks to NASA_GoddardPix for the link to the Terra picture.