We went out to Starrigavan to check on the high tide. It was forecast to be one of the highest of the year, and there was a bit of atmospheric bonus that looked promising to get higher than that from back at the beginning of the year. It did end up being higher, but it turned out not the highest. I could see by the line of grass ground into the road that the tide had been an inch or two higher (not too long) previously. I may write up a separate post about that.

This evening I was lucky enough to catch a very young moon setting. It was pretty amazing, and I feel fortunate to have even got the shots I have here – as it was only visible for a short time and I didn’t have a good setup to try and capture it with my camera (but I did have my camera, which I had almost left at home, since it was dark).

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This morning the kids and I took advantage of sunny weather and a low tide to visit John Brown’s Beach and check out some of the work being done by some visiting scientists. They were setting up experiments in about 20 small tide pools. At the time they were simply working on the setup and getting preliminary measurements that they would use to compare with similar measurements taken during and after the treatments were applied. In this case they planned to either warm tide pools or increase acidity (by bubbling CO2 through). [I later spoke with them for my radio show about their experiment and more]

This evening I happened to notice the sunset was shaping up to be pretty colorful, so I quickly went down to Swan Lake and took a flurry of photos over about 10 minutes of one of the more spectacular sunsets I have ever seen. While I was working on processing them, I noticed that noctilucent clouds appeared to be forming, so I went out again around midnight to get some pictures of them.

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I was up before 6 this morning and took a walk down to O’Connell Bridge. It was enjoyable to take some long-exposure photographs in the predawn light.

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The sky is just starting to lighten behond the mountains to the east.

A troller headed out leaves an odd pattern of light trails behind it in this long exposure.

The Sisters are in Silhouette behind the sodium vapor lights casting their yellow glow over the boats in Crescent Harbor.

City lights illuminate O'Connell bridge with Mt. Edgecumbe in the background.

City lights illuminate O'Connell bridge with Mt. Edgecumbe in the background.

O'Connell Bridge before dawn.

A bright glitter path illuminates the waters of Sitka Sound below a nearly moon.

This pale green glow behind Gavan Hill was the first aurora I had seen in over 2 years.

Over the past couple of years the sun has been in a solar minimum, a consequence of which has been auroras that are only rarely strong enough to be seen from Sitka. Combined with frequently cloudy skies, the northern lights have not been easy to observer around here for quite a while. A couple of days ago, I noticed the aurora forecast from the UAF Geophysical Institute was for active aurora (4 on a scale from 0 to 9), which meant there was a reasonable possibility that there would be some action in the northern skies.

Skies were clear and it was a moonless night, the satellite-based map of northern hemisphere aurora showed high aurora extending over Southeast Alaska, and I heard someone else had seen a burst of activity, so I checked a couple of times and at one point spent a half an hour watching. I never saw anything more than a pale green glow, mostly visible as a slight brightening of the sky behind Gavan Hill. A long camera exposure made the green of the aurora much more visible, though it also resulted in somewhat strange looking trees in shrubs in the foreground, as they were illuminated to varying degrees by neighborhood lights. Although not as dramatic as past shows I’ve seen here, it was nice to see the aurora again. It’s been over 2.5 years since the last time I photographed the northern lights, and I’m pretty sure that was the last time I saw them.

I took a little time while on my way home last night to shoot some pictures of the moon rising over the mountains and Crescent Bay.

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The sun shining over the waters of Sitka Sound at noon on the winter solstice.

With clear weather prevailing in the days prior to and including the winter solstice, it was a good year for observing the sun during the time when the light and warmth we receive from it is a minimum. Many of the things I noticed this year were things I was vaguely aware of before, though I spent a some time trying to improve my understanding.

The sun is dipping below the horizon near the southern-most point it will set.

On the solstice, the sun rose in the southeast at 8:39 am, with sunset occuring in the southwest at 3:21pm, 6 hours and 42 minutes later. The locations of sunrise and sunset are basically 45 degrees south of due east and west respectively. The earliest sunset actually occured a week before solstice, when it was setting at 3:19pm. The two minute gain of afternoon light was more than made up for by five minutes lost in the morning, with sunrise on 14 December occuring at 8:34am, and on 21 December at 8:39am. The latest sunrise, 8:40am, occurs about a week after solstice. It is not until 4 January that the sun rises earlier than on the solstice.

The sun reaches its highest point in the sky when it is due south. This occurred at noon on the solstice when it was 9.6 degrees above the horizon. For comparison, on an equinox, it reaches a maximum of 33 degrees above the horizon with it passing 9.6 degrees at 8:25am and 5:55pm. On the summer solstice the maximum height is 56.5 degrees above the horizon and the equivalent height of winter solstice noon occurs at 5:45am and 8:20pm. The low height of the winter sun gives us long shadows when skies are clear, and the all too familiar dimly lit days when heavy clouds are overhead.

Shadow on the rocks near Brent's Beach cabin shortly after noon on the winter Solstice.

I made extensive use of this handy sunrise/sunset Calculator (which also includes sun altitude and the time when the sun is due south) for this post.