APOD: Milky Way Over Abandoned Kilns (2011 Jul 25)

[Damon]

I would suggest that it's possible the colour has been skewed from the original photo by heavy post processing - which is apparent. I would like to see the original unprocessed image.

[neufer]

Excuse me, I wrote Kilus for Kilns.

There is an "edit" button.

It works for 24 hours (provided that some clown hasn't already responded to your post).

Doy packs

<<Who are we? We are KILUS, (Kababaihang Iisa ang Layuning Umunlad ang Sambayanan) an all women organization consisting of 500 strong women force based on Barangay Ugong, Pasig City, Philippines . Our primary objective is to help clean up mother earth and give livelihood to our less fortunate constituents. In February 19, 1999, KILUS launched its pet project “BAWAS BASURA DAGDAG KITA.” At the end of the year, December 1999, Ugong earned the title of “The Cleanest and Greenest Barangay along Pasig, Marikina and San Juan River.”

The KILUS pulot brigade circles around Pasig City buying the doy packs from funeral homes, cemeteries, schools, residential houses, wakes, dumpsites and whoever calls up with their doy packs. The linis brigade wash and sanitized the doy packs in 3 stages and dry them. With more than a million pieces of discarded doy packs bought and still needed to transform them into bags we save mother earth from these wastes going to our drainage systems dumpsites and water bodies.

Do your part, collect them and sell them to us, the KILUS Multipurpose Environmental Cooperative at 36 C. Santos St., Ugong, Pasig City.>>

Clueless Art Neuendorffer with his doy pack on his back

[Star*Hopper]

Excuse me, I wrote Kilus for Kilns.

Funny - that's what I read at first shot, too. I know of those objects however - made me go back for a closer look.
I call font-nanigans!

[Star*Hopper]

You guys are wa-a-ay overthinking this. I have it on good authority it's Sasquatch poots.

[bystander]

There is an "edit" button.

It works for 24 hours (provided that some clown hasn't already responded to your post).

Only for members who are signed in. Guests, and members who aren't signed in, don't have that option.

[t_may]

It's peculiar because the different images all have very fine star trails, and they don't seem to be lined up properly, or something,. It's really hard on the eyes.

[neufer]

There is an "edit" button.

It works for 24 hours (provided that some clown hasn't already responded to your post).

Only for members who are signed in. Guests, and members who aren't signed in, don't have that option.

Saturn5 & saturn02 apparently are members.

Presumably, saturn2 is one (or both) of those but forgot to (or forgot how to) sign in.

But why didn't he/she show up as simply 'guest?'

[bystander]

But why didn't he/she show up as simply 'guest?'

Guests can select a pen name when posting. That's why you see so many posts with names but no member link.

An example is swainy (i.e. The Code). swainy is a guest name.

[The Dawg]

The charcoal kilns are near Ely, Nevada in the Ward Charcoal Ovens State Historic Park. http://parks.nv.gov/images/wcoparkmap.jpg The ovens are oriented with the doors facing southward, east is toward the left. The snow-capped mountain could be in the Great Basin National Park. The source of the sky glow is probably Las Vegas.

You must be quite familiar with the Ward Ovens. I've lived in Nevada, but saw them. However, I have to differ with your conclusions. If the doors face south and the green glow is in the east (and a little to the north?) it can't be light polution from Las Vegas, for a few reasons: 1) it wouldn't be green; 2) it's some 250 miles away, half way across the state, too far below the horizon given the curvature of the earth; 3) Las Vegas is almost due south, not east or north east.

[neufer]

The charcoal kilns are near Ely, Nevada in the Ward Charcoal Ovens State Historic Park. http://parks.nv.gov/images/wcoparkmap.jpg The ovens are oriented with the doors facing southward, east is toward the left. The snow-capped mountain could be in the Great Basin National Park. The source of the sky glow is probably Las Vegas.

You must be quite familiar with the Ward Ovens. I've lived in Nevada, but [never ?] saw them. However, I have to differ with your conclusions. If the doors face south and the green glow is in the east (and a little to the north?) it can't be light polution from Las Vegas, for a few reasons: 1) it wouldn't be green; 2) it's some 250 miles away, half way across the state, too far below the horizon given the curvature of the earth; 3) Las Vegas is almost due south, not east or north east.

The "Dark River to Antares" would also be almost due south(, not east or north east).

The green glow is in the southeast in the direction of Hoover Dam

Nightglow

---

<<Airglow (also called nightglow) is the very weak emission of light by a planetary atmosphere. In the case of Earth's atmosphere, this optical phenomenon causes the night sky to never be completely dark (even after the effects of starlight and diffused sunlight from the far side are removed).

The airglow phenomenon was first identified in 1868 by Swedish scientist Anders Ångström. Since then it has been studied in the laboratory, and various chemical reactions have been observed to emit electromagnetic energy as part of the process. Scientists have identified some of those processes which would be present in Earth's atmosphere, and astronomers have verified that such emissions are present.

Airglow is caused by various processes in the upper atmosphere, such as the recombination of ions which were photoionized by the sun during the day, luminescence caused by cosmic rays striking the upper atmosphere, and chemiluminescence caused mainly by oxygen and nitrogen reacting with hydroxyl ions at heights of a few hundred kilometers. It is not noticeable during the daytime because of the scattered light from the Sun. Scientific experiments have been conducted to induce airglow by directing high-power radio emissions at the Earth's ionosphere. These radiowaves interact with the ionosphere to induce faint but visible optical light at specific wavelengths under certain conditions.

Even at the best ground-based observatories, airglow limits the sensitivity of telescopes at visible wavelengths. Partly for this reason, space-based telescopes such as the Hubble Space Telescope can observe much fainter objects than current ground-based telescopes at visible wavelengths.

The airglow at night may be bright enough to be noticed by an observer, and is generally bluish in color. Although airglow emission is fairly uniform across the atmosphere, to an observer on the ground it appears brightest at about 10 degrees above the horizon, because the lower one looks the greater the depth of atmosphere one is looking through. Very low down, however, atmospheric extinction reduces the apparent brightness of the airglow.

One airglow mechanism is when an atom of nitrogen combines with an atom of oxygen to form a molecule of nitric oxide (NO). In the process a photon is emitted. This photon may have any of several different wavelengths characteristic of nitric oxide molecules. The free atoms are available for this process because molecules of nitrogen (N₂) and oxygen (O₂) are dissociated by solar energy in the upper reaches of the atmosphere, and may encounter each other to form NO. Other species that can create air glow in the atmosphere are hydroxyl (OH), molecular oxygen (O), sodium (Na) and lithium (Li).>>

[candersen]

That looks very much like the green 5577 Angstrom aurora/airglow emission (¹S to ¹D transition of atomic oxygen.) In early June there was one three-hour period of Kp = 5 so depending on the dates/times that the images were taken it is possible that there was some faint aurora that could be detected with a long exposure. Airglow is usually very diffuse but certain mid and low-latitude atmospheric phenomena such as gravity waves and/or traveling ionospheric disturbances can show up as wavy or blob-like structures in the airglow which could also explain what is seen in this image.

Carl Andersen
Geophysical Institute
University of Alaska Fairbanks

[StormForces]

The "green mist" is airglow- ionized oxygen emitting at 5577. It is a common feature of the night, and when bright has sometimes been called the "black aurora". The airglow accounts for about half the natural night sky brightness.

That's an almost microsoftian answer.

The fact that it's most likely ionized oxygen glowing is obvious to anyone who's seen images of aurora. However, as it's in New Mexico, and not covering a significant fraction of the sky, it's not likely to actually *be* aurora. So, what is the *source* of the ionized oxygen? A large electrical substation? Piezo-electric effects from a fault line in the area?

And is it necessarily oxygen? I seem to remember that other elements and molecules have emission lines in that area.

I was thinking it could be mild aurora if it was taken facing north - i captured a faint green arc a few months ago in SW Utah, a night when predictions were high, and pretty much figured it was aurora. Sent it to my "astronomy guru" friend, and he agreed.

[Mahdi Zamani]

Here's a good explanation that we mustn't trust the image as a base for a scientific discussion:
The montage panorama has been warped in processing and it affected the real scale of the milky way and the rotation of the star traces. The photographer has composed 5 different pictures to create the montage and he made it without any attention to the scales. Thanks to the "geckzilla", there's another point:

There's also a strangely bright background mountain (?) on the lower left. It's nearly white! I don't have any input on the green haze but would like to offer my suggestion on the image itself, since it's an extremely simple Photoshop job. Take the photo, duplicate it, and set that duplicated layer above to multiply. Then duplicate that multiply layer again (it needs it) ... take the vibrance down a tad and you get this:

Click to view full size image

Well, that was my quick and dirty edit, anyway. If it was my own work I'd probably tweak it a little more. I hope Tom doesn't mind. It's not such a bad image as the previous comments imply but I am perplexed about the brightness of it.

In my opinion discussing on such this montage is basically wrong, though this green glow happens in reality and it's not a fiction. Here's a link of a reliable picture of the green glow: http://www.twanight.org/newTWAN/mystery ... es&id=1001

It would be great if we don't see such this montage as an APOD anymore.

[KCM]

Because Nevada is at a simlar latitude to us, this reminds me of a "green mist" we've seen here in Nebraska.

When camping at Merritt Resevoir near Valentine, Nebraska, USA, we have seen aurora and this "green mist" is exactly what they most often looked like. Just a green area on the northern (or NE or NW) horizon. When conditions are better the aurora appear as bands arching over the sky or pillars on the horizon or sheets of color moving in the sky. But I would be you dollars to doughnuts that the glow in this picture is aurora (borealis).

We will be looking for aurora again in the dark skies near Valentine at the Nebraska Star Party, July 31-August 5, 2011. (nebraskastarparty.com)

[Radarman]

The "green mist" is airglow- ionized oxygen emitting at 5577. It is a common feature of the night, and when bright has sometimes been called the "black aurora". The airglow accounts for about half the natural night sky brightness.

Chad Moore
National Park Service

When I shot the photo, a thin moon still illuminated the distant mountain to the east (the white patch on the left in the photo) while the kilns were in a shadow from a nearby hill to the west. The green mist area was most likely still moonlit. What is your opinion that it might be a reflection effect? Thanks, Tom McEwan

[Radarman]

That looks very much like the green 5577 Angstrom aurora/airglow emission (¹S to ¹D transition of atomic oxygen.) In early June there was one three-hour period of Kp = 5 so depending on the dates/times that the images were taken it is possible that there was some faint aurora that could be detected with a long exposure. Airglow is usually very diffuse but certain mid and low-latitude atmospheric phenomena such as gravity waves and/or traveling ionospheric disturbances can show up as wavy or blob-like structures in the airglow which could also explain what is seen in this image.

Carl Andersen
Geophysical Institute
University of Alaska Fairbanks

Carl, I have also asked this of Chad, above. When I shot the photo, a thin moon still illuminated the distant mountain to the east (the white patch on the left in the photo) while the kilns were in a shadow from a nearby hioll to the west. The green mist area was most likely still moonlit. What is your opinion that it might be a reflection effect? Thanks, Tom McEwan

[wilvanbreugel@gmail.com]

The kilns are interesting but this image is hard on the eyes. It's not a night sky shot worthy of APOD.

I agree. What is APOD about? I hope at the very least it would search out something more artistic and professional when looking at the skies.

[chadair]

Airglow can be either smooth across the sky, with a peak brightness at around 12 degrees above the horizon (under good transparency), or it can be skewed to one side. Interestingly, I saw the most skewed airglow ever last year at the Nebraska Star Party. It can also be banded, seem to brighten in one particular area, and changes over time. The NPS has lots of all sky mosaics that have a checkerboard pattern indicating the airglow varied over 1 minute time scales.

Here is a very good recent image from orbit that shows the 90 KM airglow layer.
http://www.space.com/12385-spectacular- ... earth.html

As the scientist from Fairbanks indicated (and they know their aeronomy) it could very well be aurora. Since aurora reach up hundreds of KM into the atmosphere, you could very well see it near the horizon from modest latitudes like 35 degrees N in the US.

I don't think it is moon reflection. Moonlight is basically sunlight skewed a little to the blue in color. Both forward scattering and backscattering of moonlight should be yellowish in color.

I have seen some really weird stuff above distant lighting storms at night- flashes of green and blue, but I'm not familiar with the physics. But maybe...

Chad Moore
National Park Service

PS. Las Vegas light pollution is visible from 210 miles, but it tends to be sodium-colored (yellow) at that distance

[Radarman]

I'm going to paste my comment on this image from Friday 15 here:
http://asterisk.apod.com/viewtopic.php? ... 55#p153455

Ann, when I shot this image I had exactly the same thought as you expressed: I wanted to juxtapose the night sky with our terrestrial landscape to connect the viewer with our universe in a way that modern people rarely if ever see. Judging from the number of critical replies to the image, it's clear not many have experienced a remote night sky in Nevada. It remains as the pioneers must have seen it, and rather than being pitch black, the moonless night sky is very bright with a light gray between the stars. The milky way is awesomely bright. I shot each of five frames in the panoramic image at f/2, 75 sec and ISO 3200. You can easily calculate that to be about 1,000,000 times dimmer than daylight. Yet the camera's histogram was nicely spead with virtually no clipping on either the land or sky. There was a dark histogram hump for the landscape and a light hump for the sky, about 3 or 4 stops brighter. Yes, the sky was very bright! Photographers would recognize the histogram to be essentially identical to a daytime shot on an overcast day. And why wouldn't it be with all those stars providing uniform illumination. Aside from stretching the land and sky histograms as one would do for any photo, the tonal range is quite normal. Shockingly normal, as the colors in the landscape were perfect balanced. I ended up making the landscape somewhat dark for realism, otherwise it looked like totally normal daylight. The sky was rich in warm tones and not as I saw it visually, so I added some blue to the sky to better match my visual impression and to better agree with the lay public's idea of the night sky (bluish). The pioneers at the kilns also saw the Milky Way as a bright bluish-white. Regarding using a panoramic stitching, let's face it, normal cameras map a 3D world onto a 2D image plane. Very distorted and unrealistic at wide angles. A panoramic image works more like the human eye. I tried shooting the image with a 17mm lens and all the kilns were falling over backwards and didn't fit in the image. The panoramic is so natural that most viewers don't realize the image is about 100 deg wide. Just look at how the doorways appear to rotate on the image. One final comment, the white mountain at the extreme left is moonlit by a thin moon, while the kilns were in the shadow of another mountain. Sorry to be so wordy, but I feel some explanation for the naysayers is needed. Tom McEwan

[alter-ego]

The charcoal kilns are near Ely, Nevada in the Ward Charcoal Ovens State Historic Park. http://parks.nv.gov/images/wcoparkmap.jpg The ovens are oriented with the doors facing southward, east is toward the left. The snow-capped mountain could be in the Great Basin National Park. The source of the sky glow is probably Las Vegas.

You must be quite familiar with the Ward Ovens. I've lived in Nevada, but saw them. However, I have to differ with your conclusions. If the doors face south and the green glow is in the east (and a little to the north?) it can't be light polution from Las Vegas, for a few reasons: 1) it wouldn't be green; 2) it's some 250 miles away, half way across the state, too far below the horizon given the curvature of the earth; 3) Las Vegas is almost due south, not east or north east.

FYI, I have a few comments about this:
1. I've identified the camera location and headings for the APOD (within a few degrees). I estimate the FoV for the 6 kilns to be ≈70º
- Camera location : Lat≈ 39° 2'13.95"N; Long ≈ 114°50'51.51"W
- The small peak between kilns #2 and #3 is at an absolute heading ≈144º (0º = North, 90º = East)
- The green blob is at a heading ≈ 121º
2. Dawg, you are certainly right about Las Vegas not being the source of the green blob. It is at a heading ≈ 185º (almost due south) which puts in right behind kiln #1 (on the right), so it is
not possible to verify if it is visible in the APOD.
- One correction, Las Vegas is 200 miles from the kilns not 250.
- I have been to southern NV and could visually see sky glow from Vegas lights 130 miles away. Could this Vegas glow be photographed from the kiln location? Yes, according to Chad Moore.
3. Cedar City (pop. 28,000) is 135 miles away at a heading of 134º. Now, I don't believe that ground lighting can neccessarily be excluded ipso facto. We don't know the exact spectral content of the green glow, and we certainly know that many effects contribute to the color that we see in the image. It is clear in the APOD image blues and reds are enhanced from visual experience, and I've seen city light sky glow pictures that indicate a strong green component, e.g mercury vapor lighting. However, the APOD green glow is 10º further east from Cedar City, and expecting to see a city at 130 miles that is 1.4% the size of Vegas (and relatively much less lit!) does not add up.

I believe natural air glow is the best answer, assuming it can appear in discreet patches as it looks in the APOD.
I question aurora because I have never experienced an aurora (Seattle area) popping up on the southern horizon and no where else. I.e. aurora borealis activity "grows" from the north and migrates southward (every time in my experience). I keep track of the auroral oval (and the KP) and this trend is very strong. I can certainly believe seeing an aurora on the northern horizon, but not an isolated blip near the southern horizon. The auroral activity to the north is always very apparent if there is a visible zenith aurora. I believe if Tom did not see any broad-area auroral activity that night, the green glow is not a localized aurora in his picture (I also don't think this is an aurora australis either)

Tom - I've seen fantastic skys from dark locations in Washington, very dark skys in Nevada, and Australia. My opinion is your image, which is visually astounding, has exaggerated color balances which really help bring out the sky's beauty as you want to show, but are not directly experienced by eye. Maybe the image colors are all in the right proportion(?), but I don't trust the faint green glow as really being "green", at least not enough to preclude a ground light source, like a city or nearby well-lit farm. My criticism is meant to relate only to the details of the green glow, and not the quality of your work.
I think it's a great composition and I'm glad you submitted it!

[CountryTrekker]

If the doors on the kilns face south, then the camera was facing north-northwest, and the green light could not possibly be Las Vegas, which is 200 or so miles to the south of Ely. Perhaps it is Elko or Spring Creek, but can a small town make a large, green glow from 150 miles away? In my experience the aurora makes this odd-shaped green glow, while cities make domes of white or pale yellow, with a wisp of sodium lights' pinkish orange.

[kentB]

I think the picture is amazing those many starsfor five shots. Its unspeakable how moved i get by every pic. so I think the green mist must obviously be radioactive dus in the air. from Nevada and Idaho. Because it might get stirred up mining it and steered in their direction from rising air going over those moutainous areas. and because its dark. that greenglow is probably the uranium dust from out west. im just saying. it could be a refletion of green collored light hitting some dust high in the atmosphere on the crecsent of light from a sunrise but i like my previos idea.

[owlice]

Info on airglow: http://www.atoptics.co.uk/highsky/airglow1.htm
http://www.atoptics.co.uk/highsky/airglow2.htm
http://www.atoptics.co.uk/fz378.htm

[Chris Peterson]

I question aurora because I have never experienced an aurora (Seattle area) popping up on the southern horizon and no where else. I.e. aurora borealis activity "grows" from the north and migrates southward (every time in my experience). I keep track of the auroral oval (and the KP) and this trend is very strong. I can certainly believe seeing an aurora on the northern horizon, but not an isolated blip near the southern horizon.

I've photographed low-level auroras (too dim to be visible) all over the sky, including to the south. They tend to be diffuse streamers that can appear anywhere. So I have no reason to think this couldn't be a photographic aurora, even towards the south- especially given that a significant CME hit the Earth right around the time the picture was taken. Of course, skyglow is also a likely explanation, although atmospheric extinction makes such a strong band of skyglow so near the horizon unusual.

[sOnIc]

Sorry, but I agree with those saying this image is a bad APOD.

The foreground was shot in daylight right? I can see that from the remaining background visible bottom left.

It's a bad Photoshop job, inaccurate and misleading. Photoshop should be used to correct and perfect images; not create them.

APOD has some amazing images, but the standard is not consistent.