Tag: sky

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With any luck I’ll finally post about last week’s trip to Las Vegas soon, but meanwhile, here’s something interesting that we spotted a couple of times on the drive back: The shadow of a contrail against the sky.

Here’s what it looked like, as the camera saw it. Actually, it was much more visible at the start. It faded considerably in the time it took to get the camera out and snap the photo.

Contrail and shadow, unprocessed

And here it is with the contrast enhanced. You can see a dark line extending across the sky from the end of the trail down to the lower left. The sun was at the upper right, almost but not quite in line with the trail at that point.

Contrail and shadow, with contrast enhanced

Atmospheric Optics has a huge collection of cloud shadows, rays, rainbows, ice halos, and more, including a diagram of how contrail shadows work.

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The skies were surprisingly clear today. Four of us at work walked outside after sunset to a bridge near the office, and saw Comet McNaught. It was visible from ~5:10/5:15 to 5:28, at which point it slipped below the line of hills to the west.

We saw it against the red sky, slowly dropping through the (fortunately sparse) clouds. It was easily visible to the naked eye as a fuzzy white spot, with a hint of a tail pointing straight up that was a lot clearer in binoculars. The tail looked like a U or a V, fanning out at what looked like (but probably wasn’t) a 45° angle.

Well, my fingers are finally warming up. (I made the mistake of not grabbing my jacket, and went out just in my sweater.) Time to wrap stuff up.

Update January 13: I managed to catch another glimpse of it tonight. Unfortunately I was just arriving at the shop to pick up my car, and it was just closing, so I didn’t have a chance to watch it set (or see much more than a fuzzy white dot.) My watch said 5:02. By the time I got out, it had set beneath the building across the street, and there just wasn’t anywhere nearby enough with a clearer view of the western horizon.

On the plus side, I did manage to spot Venus while the sky was still light, and get a picture. It’s not quite as exciting as spotting it at one in the afternoon, but by adding more blue, you get an idea of what that looked like:
Venus in a light sky: actual on the left, colorized on the right

Update January 14:

I was looking over the photos I took last night (Saturday) and discovered I could actually find it by messing around with levels. On the left is the original photo, with a little bit of color correction to match what the sky looked like. The background’s still too bright to see the comet, though it was visible to the eye. On the right, I’ve adjusted the heck out of the image, and there’s a very slight bright spot right where it should be (I framed the shot so that the comet would be near the light pole, making it easier to find). Actually, now that I look at it again, it’s just barely visible in the less-processed photo on the left.
Comet McNaught - original photo on the left, processed on the right.

Also, this is cool: the comet has gotten bright enough to be spotted in daylight. (via Slashdot) I didn’t have any luck looking for it this afternoon, but I chalk that up to lower altitude and city haze.

Update January 15: I spotted something today, but I’m not sure what…

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Here are a couple of photos, one just before sunset, the other just after, over the past month.

First up is a twilight view of South Coast Plaza. On Friday the 13th, we went to the nearest Borders to pick up The End of Lemony Snicket’s Series of Unfortunate Events and Neil Gaiman’s new short story collection, Fragile Things. We ended up crossing the bridge over to the main section of the mall, turned around, and saw an amazing twilight display with clouds silhouetted against the blue.

We stopped to take pictures. We weren’t the only ones.

Looking across a yellow-lit parking lot toward a long, low building, and above it a blue sky (fading to yellow closer to the horizon) with clusters of clouds, some dark gray, some lit from below.

Perhaps an hour later, the rainstorm arrived.

Next up is from this past Monday, October 23. I was driving up the 405 after work and noticed that there were some feathery clouds in the right area, so I started looking for sundogs. Normally I don’t find anything. It’s Southern California, after all, so the right conditions are relatively rare. (Though occasionally I see something spectacular like the full halo I caught in February.)

To my surprise, I saw a faint bright spot in the clouds, level with and to the right of the sun. It got brighter over the course of my drive, with hints of red, orange and yellow creeping in on the sunward side: a classic sundog. Once I got onto city streets, I had a chance to stop and take a picture.

The long boom of a traffic signal and street sign are silhouetted against a blue-gray sky banded with clouds. There is a bright spot in the clouds, white fading to yellow and red toward the left.

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Monday morning dawned foggy. By the time we left for work, most of the fog had burned off, but we looked out the car window and saw a huge, billowing gray cloud hugging close to the ground. If this had been the usual fire season, or if there had been no fog to start with (or if there had been time for coffee to take effect), I think we would’ve both immediately recognized it as smoke from a brush fire. The Sierra fire in the Cleveland National Forest had started just a few hours earlier.

Sierra Fire Smoke on Monday morning, blending into fog

There was still fog around, though. Continue reading →