A clear 22-degree halo around the sun, bright enough that I didn’t have to adjust the image afterward. This is straight from my phone.
Even cooler: you can actually see the contrail’s shadow on the layer of cloud that’s producing the halo! The sun is behind the tree, and while the contrail pops out so it looks closer than the almost uniform layer, it’s clear from the shadow that the contrail is higher.
I could barely see any colors in the cloud at all without my polarized sunglasses, and when I took a photo through them, I still had to bump up the saturation.
I’ve seen several of these over the years. The brightest one was nine years ago, while the longest was just last year. It’s a solar halo caused by reflections inside ice crystals (near ground level or higher up in the atmosphere) that in theory could circle the entire sky parallel to the horizon. In practice, it’s rare for ice crystals of the right shape and orientation to cover more than a small area from any given viewpoint, so mostly people see fragments of them.
When I first started paying attention to solar ice halos, I read about tangent arcs. But this is the first time I’m sure I’ve seen one. The tangent arcs appear above and below the sun, branching out from the 22° circular halo (which you can see here, very faintly), and change shape depending on how high the sun is in the sky.
It was late afternoon, and the sun was behind the next building over. I ended up snapping a shot with my phone, wishing I could have grabbed a better camera, but the Pixel 2 caught a surprising amount of detail once I adjusted the brightness to bring it out. (No, the sky wasn’t this dark!). It’s a far cry from the G1’s photo of a very blue (and blurry) set of halos 10 years ago, or even the Galaxy S4’s colorless rainbows at sunset four years ago.
A hole-punch cloud, also known as a fall-streak hole, seen from Redondo Beach, looking toward LAX airport. These form when an airplane passes through a thin cloud layer, disrupting the cloud.
I noticed the halo around the sun as soon as I walked out the door for lunch on Thursday. The rainbow cloud? That appeared as I walked past a building. I saw it as soon as the southern sky came into view again.
The colors got more intense over the next few minutes, and I kept taking photos until my phone locked up. I stood there watching the colors intensify, then fade, while I pulled out the battery and waited for the phone to reboot.
A man who’d been sitting nearby, buried in his phone, looked up wondering what I was taking pictures of. He’d never seen anything like it before, and wondered what it was, and fortunately I was able to answer.
At the right angle, ice crystals in a cirrus cloud refract sunlight to produce a feathery rainbow effect. The circumhorizon arc runs parallel to the horizon, and while it can be long, it’s usually only seen in fragments like this. I’ve only seen a few of these myself, and it’s been years since I’ve seen one this intense. I took this photo through my polarized sunglasses, but the colors were bright even without them.
When my phone froze, he offered to send me one of his pictures just in case mine hadn’t actually saved. Fortunately they had, and I actually posted to Flickr several hours before his message made it through the cell network.
Within a few minutes, the cloud had drifted out of alignment, and the colors had faded completely.
An hour later, on the way back from lunch, I noticed a longer patch in a smoother cloud layer, but it was faint enough that I could only barely see it with my sunglasses on. Without them, it faded completely into the glare.
If I’d had my better camera with the zoom lens, I would have gotten some better shots of just the bright cloud. Then again, I wouldn’t have been carrying it with me to lunch, and the effect was gone in the time it would have taken to run back in and get it. So it’s probably just as well I stayed and watched instead.
Funny thing: I posted a cropped view on on Instagram featuring just the arc fragment and contrail. When I went back to look at the #rainbowcloud tag last night, I found no less than SIX other photos of what was clearly the same cloud at various points in its five-minute lifetime!
