Ridiculously Beautiful Clouds over Denver

Slate -- 4 January 2014

By Phil Plait

This is real. Seriously. I was there, and took this picture with my phone. Click to ennebulenate.  

Photo by Phil Plait

Over the weekend I was in Denver to do a talking head gig for an upcoming science documentary (I’ll have more on that when it’s closer to airing). After we finished for the day I went outside to load up my car, and I do what I always do: I looked up at the sky. The Sun was just setting, and to the east was a bank of clouds… but one so ridiculously and jaw-droppingly spectacular I ran inside to grab the crew and show them.

We stood outside for the next 15 minutes just gawking at them, trying to figure out what was shaping them into such delicate formations. There were layers inside of layers, festoons, swirls, and larger structures clearly sculpted by winds (called lenticular clouds).

I took a bunch of photos, and decided to do a quick impromptu video.

[You seriously want to make that high-def and at least enlarge it, if not make it full screen.]

Phil Plait

Phil Plait writes Slate’s Bad Astronomy blog and is an astronomer, public speaker, science evangelizer, and author of Death from the Skies!

The video only captures a fraction of the glory we saw, but hopefully you get the idea. The iridescent clouds were lovely, too; I see them quite a bit in Boulder over the mountains to the west. The most obvious colors are usually pink and green, so I call them Izod clouds. But once, a few years ago, I saw some studded with deep crimson, yellow, orange, green, teal, purple… it was magnificent. The physics is actually somewhat complicated, but the colors are due to the wave nature of light; the incoming light from the Sun is broken up by ice crystals or tiny raindrops, and the waves interfere with each other (like waves in the bathtub) creating the various colors. It’s really striking.

There are a lot of reasons to love living in this area, but if you like weird and fascinating  (and sometimes nerdy) clouds, this place is hard to beat.

But the lesson here is independent of where you live: Look up. If you do it enough, the sky will deliver.