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Anticrepuscular Rays over Colorado (II)

Explanation: What's happening over the horizon? Although the scene may appear somehow supernatural, nothing more unusual is occurring than a setting Sun and some well placed clouds. Pictured above are anticrepuscular rays. To understand them, start by picturing common crepuscular rays that are seen any time that sunlight pours though scattered clouds. Now although sunlight indeed travels along straight lines, the projections of these lines onto the spherical sky are great circles. Therefore, the crepuscular rays from a setting (or rising) sun will appear to re-converge on the other side of the sky. At the anti-solar point 180 degrees around from the Sun, they are referred to as anticrepuscular rays. Featured here is a particularly striking display of anticrepuscular rays photographed earlier this month in Westminster, Colorado, USA.

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... Or something big is happening at Denver International Airport.

Love those rugged Colorado horizons.

Did you notice the shaded side of the fence posts on the left side of the scene show the sun at your back and to the left while the fence posts
on the right side of the scene show the sun at your back and to the right!!

franbeaman2@outlook.com wrote:Did you notice the shaded side of the fence posts on the left side of the scene show the sun at your back and to the left while the fence posts
on the right side of the scene show the sun at your back and to the right!!

As would be expected. All shadows will appear to converge at an invisible point which is under the horizon for this image, though the light is too scattered for any hard ground shadows to appear.

Nitpicker wrote:Love those rugged Colorado horizons. :wink:

Of course, it's the rugged horizon to the photographer's back that makes Colorado such a good place to see anticrepuscular rays.

Earlier this month I took a panorama of crepuscular/anti-crepuscular rays from horizon to horizon - also in Colorado, at the Devil's Backbone near Loveland. It was one of the few times I've actually seen both divergence then convergence of the rays. Of course it looked a bit better than my picture shows. It was awkward taking the panorama with my cell phone over my head. The rays are easier to follow in the B&W version.
https://www.dropbox.com/sh/xxrtoyae7o7x ... hYkIa?dl=0

What's most striking is the uglyness of human urbanization

APOD = Earth; ESPOD = Mars. Go figure!

ygmarchi wrote:What's most striking is the uglyness of human urbanization

It's true we humans rarely build anything that relates directly to or derives directly from the natural environment, but that doesn't necessarily equate to uglyness. There's little that is natural about, say, Picasso's Sunflowers, but most people agree it's a beautiful painting nonetheless. And don't forget that we arise from the environment and therefore, by definition, our urbanization is natural in some sense. If you find it ugly despite its naturalness, what solution do you propose?

Rob

Once buildings were usually built from materials from the surrounding areas, so they merged better with the environment.
The buildings surviving from the past are often the most valuable and beatiful of their times.
In the past architectural style had the time to settle though a process of refinement,
now it's often simply the effimeral fruit of the architect whims.
Poorer places tend to have uglier buildings,
but it's where there's only money and greed without culture that you find the worst buildings.

Interesting....

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ygmarchi wrote:Once buildings were usually built from materials from the surrounding areas, so they merged better with the environment.

Given the cost of transporting materials, I would guess that most of the bulidings we see in this picture are also built from relatively local materials. Local materials don't ensure beauty. Where the materials come from have effectively nothing to do with the result. Craftsmanship and good design will help, a lot.

ygmarchi wrote:The buildings surviving from the past are often the most valuable and beatiful of their times.

Generally they are also the most expensive, built by the wealthiest people, else they wouldn't have survived. We've been taught they are the most beautiful, but that's not a universal truth. Many are just pastiches of older design elements.

ygmarchi wrote:In the past architectural style had the time to settle though a process of refinement,
now it's often simply the effimeral fruit of the architect whims.

Architects are artists more than engineers, and sometimes move a little too far and fast for the viewers of their work. But give it time. We'll get used to it and will then be able to see the beauty in at least some of the newest buildings. (And you should know that many modern buildings have no architect behind them at all, just "design/build" companies.)

ygmarchi wrote:Poorer places tend to have uglier buildings,
but it's where there's only money and greed without culture that you find the worst buildings.

Are you referring to the neighbourhood in this picture? Is it poorer? Or is it the result of money and greed without culture? I can't tell just by looking at the picture.

Rob

The photo could, for some reason known only to my spririt, be titled, "The Greening of Mars."

"Crepuscular" means "pertaining to twilight," so, technically, shouldn't "anti-crepuscular" refer to noon or midnight?

I was once startled to hear a wildlife biologist refer to mountain lions as "crepuscular." So if you see crepuscular rays, it can't hurt to look around, just in case.

All kidding aside, I think anti-crepuscular rays are one of the most beautiful atmospheric phenomena. On occasion, you can see them stretch all the way across the sky to merge with crepuscular rays.

geckzilla wrote:

franbeaman2@outlook.com wrote:Did you notice the shaded side of the fence posts on the left side of the scene show the sun at your back and to the left while the fence posts
on the right side of the scene show the sun at your back and to the right!!

As would be expected. All shadows will appear to converge at an invisible point which is under the horizon for this image, though the light is too scattered for any hard ground shadows to appear.

I think what geckzilla is referring to is that three sides of the posts are dark, and only one is lit brightly due to the fences being aligned roughly north/south.
You see the same bright side, but you also see two different dark sides on the left vs right of the picture, which looks makes it look strange.

You could take an art class or watch some video tutorials on basic perspective and get a better idea about it. It doesn't look strange even in the slightest.

geckzilla wrote:You could take an art class or watch some video tutorials on basic perspective and get a better idea about it. It doesn't look strange even in the slightest.

Strange is really not the word but beautifully peculiar might do .. there is something about the lack of balance in the photo that is not ugly .. but to me the lack of balance gives a soft focuses of the eyes on the green rather than the rays, which are supposed to be the center of attention .. otherworldly is a word that comes to my mind, in a beautiful sort of way, not horribly frightening and gruesome as in the movie ''Mars Attacks.' (just joking about the movie of course.)

The third "anticrepuscular rays" link in the explanation should apparently bring up a video but that is not available (at least on my internet connection) using two browsers. As nobody has made any comment about a failed link I assume that it must be a problem with my internet. I would be grateful therefore to be informed if the video is directly related to the APOD and if so does it have any information, such as the date the image was taken "earlier this month" stated in the explanation? Thanks.

DavidLeodis wrote:The third "anticrepuscular rays" link in the explanation should apparently bring up a video but that is not available (at least on my internet connection) using two browsers. As nobody has made any comment about a failed link I assume that it must be a problem with my internet. I would be grateful therefore to be informed if the video is directly related to the APOD and if so does it have any information, such as the date the image was taken "earlier this month" stated in the explanation? Thanks.

It's dead, Jim. Er, David. Nothing you can do about it. No clue what was once there.

geckzilla wrote:It's dead, Jim. Er, David. Nothing you can do about it. No clue what was once there.

"anticrepuscular rays"

bystander wrote:

geckzilla wrote:It's dead, Jim. Er, David. Nothing you can do about it. No clue what was once there.

"anticrepuscular rays" :?:

That's not a bad guess. But given the propensities of the APOD editors, I wouldn't rule out a cat doing something cute.

Chris Peterson wrote:

bystander wrote:

geckzilla wrote:It's dead, Jim. Er, David. Nothing you can do about it. No clue what was once there.

"anticrepuscular rays"

That's not a bad guess. But given the propensities of the APOD editors, I wouldn't rule out a cat doing something cute.

A cat shooting lasers from its eyes during crepuscular hours, maybe.