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NASA Snaps Mysterious "Night-Shining" Clouds
coondoggie writes to tell us that NASA has captured some pretty impressive images of the Alluring noctilucent (or "night-shining") clouds. These clouds are made up of ice crystals and dust and are formed at high altitudes near the poles. "Very little is known about how these clouds form over the poles, why they are being seen more frequently and at lower latitudes than ever before, or why they have been growing brighter. AIM will observe two complete cloud seasons over both poles, documenting an entire life cycle of the shiny clouds for the first time. 'It is clear that these clouds are changing, a sign that a part of our atmosphere is changing and we do not understand how, why or what it means,' stated AIM principal investigator James Russell III of Hampton University, Hampton, Va. 'These observations suggest a connection with global change in the lower atmosphere and could represent an early warning that our Earth environment is being changed.'"
writes to tell us that NASA has captured some pretty impressive images of the Alluring noctilucent (or "night-shining") clouds.
At this time of day? localized entirely in your kitchen?
The theory of relativity doesn't work right in Arkansas.
That may well be entirely true, but I recognize a cousin to the "...and therefore may lead to new treatments for cancer." that molecular biologists ritualistically slap at the end of every grant application.
What I'm listening to now on Pandora...
We hear too often from these climate "experts", finally someone is ready to admit that our climate is so big and complex that we don't know exactly how it all works.
it's sommat to do wid dem bars wid de amor plats fiting wid de tartans and dat brass spinny thing.
A feeling of having made the same mistake before: Deja Foobar
It is clear that they are caused by global warming.
So some weathermen that work for NASA say the world is ending? Why do this chuckleheads get more credibility than their brothers at the local ABC affiliate?
I'll be taking a nap. Call me back when they have evidence.
Virginia is for lovers. EVE is for griefers.
Even more worryingly, early reports suggest they may contain Dihydrogen Monoxide.
If you haven't made a developer cry, you've wasted a day.
http://www.spaceweather.com/nlcs/gallery2007_page9.htm has a Noctilucent Cloud gallery. I haven't seen them yet myself, but it'll be interesting to see if AIM manages to find an explanation for them. It's an intriguing mystery!
Murphey's fighting Occam, and we're in the stands.
Don't mod down just because you don't get the reference. How anyone could possibly not get the Simpsons reference here, I have no idea. Hand in your damn geek cards.
- None can love freedom heartily, but good men; the rest love not freedom, but license. -- John Milton
"All right, Beatrice, there was no alien. The flash of light you saw in the sky was not a UFO. Swamp gas from a weather balloon was trapped in a thermal pocket and reflected the light from Venus."
I'm waiting for a "-1 somepeoplejustshouldn'tgetmodprivileges" meta-moderation.
Holy crap, someone better get Al Gore on this right away! Nevermind the fact that the story broke nearly 6 months ago.
From somewhere on the Internet:
Dihydrogen Monoxide! The Invisible Killer
Dihydrogen monoxide is colourless, odourless, tasteless, and kills uncounted thousands of people every year. Most of these deaths are caused by accidental inhalation of DHMO, but the dangers of dihydrogen monoxide do not end there. Prolonged exposure to its solid form causes severe tissue damage. Symptoms of DHMO ingestion can include excessive sweating and urination, and possibly a bloated feeling, nausea, vomiting and body electrolyte imbalance. For those who have become dependent, DHMO withdrawal means certain death.
Contamination Is Reaching Epidemic Proportions!
Quantities of dihydrogen monoxide have been found in almost every stream, lake, and reservoir in America today. But the pollution is global, and the contaminant has even been found in Antarctic ice. DHMO has caused millions of dollars of property damage in the midwest, and recently California.
Despite the danger, dihydrogen monoxide is often used:
* as an industrial solvent and coolant. in nuclear power plants.
* in the production of styrofoam. as a fire retardant.
* in many forms of cruel animal research. in the distribution of pesticides.
* Even after washing, produce remains contaminated by this chemical.
* as an additive in certain "junk-foods" and other food products.
Companies dump waste DHMO into rivers and the ocean, and nothing can be done to stop them because this practice is still legal. The impact on wildlife is extreme, and we cannot afford to ignore it any longer!
The Horror Must Be Stopped!
The American government has refused to ban the production, distribution, or use of this damaging chemical due to its "importance to the economic health of this nation." In fact, the navy and other military organizations are conducting experiments with DHMO, and designing multi-billion dollar devices to control and utilise it during warfare situations. Hundreds of military research facilities receive tons of it through a highly sophisticated underground distribution network. Many store large quantities for later use.
It's Not Too Late!
Act NOW to prevent further contamination. Find out more about this dangerous chemical. What you don't know can hurt you and others throughout the world.
I've seen these a few times over the last years. The examples I saw weren't as brilliant as the ones in the summary (more along the lines of http://www.spaceweather.com/nlcs/gallery2007_page1.htm), but they are still very beautiful. I never realized they were a special subset of clouds.
Post-rock/Ambient/Drone and other noise.
to fight this symptom of global warming. He just doesn't care.
You see, a low cloud blocks some sunlight coming in, but also blocks infrared going out. A very high cloud, however, blocks the same amount of sunlight ( not being significantly closer to the sun ) and blocks less infrared because only inrared going straight up will hit it. This works unless there is nearly 100% cloud cover.
Global warming is the big scare in the climate world right now, so it is how you get money for environmental research. You write a proposal to study some owl that isn't endangered but might become so that nobody gives a shit about and you get no money. However you change it up and talk about how you want to study the impact of global warming on it, bam you gots money.
Same shit with terrorism in other areas. Can't get money for an anti-crime initiative? Just make it an anti-terror initiative! You get money thrown at you. Hell, ConEd did that with their new superconducting power line. They wanted government help building the thing so they spun it is being resistant to terrorist attack. Maybe true, but that isn't why they are doing it. They are doing it because the old system failed due to overload, not attack.
It is sadly common in the world, and research is no different. You find what is hot in a given field and you'll see all kinds of shit that shouldn't be getting tied in to that to try and get money.
Oh no ;). Maybe we should ban the production and use of Dihydrogen Monoxide in commercial products. It think some town in California has tried that already with little success. Maybe this can create a much larger effort with more support.
We already know that Dihydrogen Monoxide has a large green house properties and is probably more prevalent in the atmosphere then Co2. It just makes sense to ban it.
Where in the article does it say anything about the world ending? Or that the investigators were "weathermen?"
Clearly, you are the one who is jumping to conclusions without examining the evidence.
Enjoy your nap. Maybe you'll be a bit less cranky when you wake up.
Driving home, about an hour and a half ago: I saw a launch from the cape.
Anyone know anything?
It was not a shuttle.
I am the unwilling control for my Origin.
Or they could be the result of something as simple as rocket exhaust...
Calling them a "clear symptom" of global warming is a bit hasty IMO.
Murphey's fighting Occam, and we're in the stands.
I at first thought NASA snapped its fingers and waved a wand,
and there were singers of stars in the pond...
Maybe they will increase the budged by offering their version of "Name Your Star" for the low, low price of... $350
Previously: "Linux... Toward the Sunrise..." Now: "Linux... Toward the-- No, now, part of Every Sunrise"
If you go through these pictures ...
...
http://www.spaceweather.com/nlcs/gallery2007_page9.htm
Nearly every single cloud structure is filamentary. People will surely say it's blasphemous to use the E-word, but structures like these
http://www.spaceweather.com/nlcs/images2007/16jun07/Heden1.jpg
Are what you get in the laboratory with *electrical* plasmas. It's the same structure that you get in a novelty plasma globe. These look exactly like Birkeland Currents to me. I'm not even sure that "clouds" is the proper term for these things, given their proximity to space. Even the overhead view from the article in question demonstrates filamentation.
"A man cannot begin to learn that which he thinks he already knows." --Epictetus, 1st Century A.D.
We told you not to drink that stuff outa the toilet. That's why there's Brawndo! It's got electrolytes!
The White House is already taking steps to make sure that these "scientists" at NASA don't say anything that might upset you:
Climate Science Manipulation Alleged
Obviously, this report didn't get properly vetted. By the end of the day it should be titled "Unday Clouds Shine Pretty! Doubleplus Good!"
when the clouds are positioned for coverage around the globe . . .
checkmate
One theory trying to explain these clouds is the X-ray activity of the sun. The sun is a highly variable star when it comes to X-rays. During its 11-year cycle, the X-ray flux emitted by the sun varies by a factor of 15, with ferocious bursts. We are at a solar minimum, so we see few sun spots and the X-ray activity is also lower on average.
I found an article that is short and readable explaining the link between solar cycles and X-rays: http://solar.physics.montana.edu/nuggets/2000/000407/000407.html. Note that the X-ray activity can vary hugely from the current solar minimum to, say, the 2000-2001 solar max.
The problem is that we don't have that much data on it yet. We need to accumulate several cycles worth of observations before we can answer these questions:
* When does the sun emit X-rays? Is it linked to sun spots?
* What do solar X-rays do to the upper atmosphere?
The X-rays are absorbed by the ionosphere (fortunately for life forms), and this energy transfer is not well known. During each solar minimum, less X-rays arrive in the upper atmosphere, which therefore should cool down. Is it the reason why we see these noctilucent clouds? If so, they should start disappearing in a couple of years, when sun spots return.
This is a very interesting keyhole on a yet unknown mechanism. I hope we'll see updates on the subject.
Fantasy: http://ferrisfantasy.blogspot.com/
"These observations suggest a connection with global change in the lower atmosphere and could represent an early warning that our Earth environment is being changed."
not warmed, not cooled, changed. everybody's a winner!
Scientists have studied the phenomenon from the ground and from the perspective of the satellite imagery. They have found that the impressive appearance of illumination, is actually reflective. They have been unable to conclude what is the cause of the increase in the frequency of the phenomena.
A leading researcher commented as follows:
I've looked at clouds from both sides now
From up and down, and still somehow
It's cloud illusions I recall
I really don't know clouds at all
If I were to tell you that that was the monthly lunar transfer pod taking Karl Rove to Expedition Habitat Prime on the far side of the moon so he can shed his humaniform exoskeleton and enjoy a week of R&R splashing in a recreation of the methane swamps of his home planet I'd be [MESSAGE ENDS]
I wonder if the same thing is happening in the South Pole?
My ism, it's full of beliefs.
"Very little is known about how these clouds form over the poles, why they are being seen more frequently and at lower latitudes than ever before, or why they have been growing brighter. AIM will observe two complete cloud seasons over both poles, documenting an entire life cycle of the shiny clouds for the first time."
"These observations suggest a connection with global change in the lower atmosphere and could represent an early warning that our Earth environment is being changed."
* It could also suggest that documentation has been poor in the past (ref. quote 1) and that the higher rate is because more effort is spent on registering the climate in general.
* It could also suggest a _purely local_ non-human-related change. After all, the middle ages warm period has been discounted by climatologists as a purely half-a-hemisphere local phenomenon. There is hence no reason why the climate should not change in one region of the world alone.
* It could also suggest a _purely local_ human-related change, e.g. if it is related to soot in the atmosphere, or NOx
* It could also suggest a _cyclical_ event, either globally or locally, which the expressions used ('is being changed') alludes away from.
Simply saying "The observations could suggest that XYZ" is an unprofessional statement. All observations could suggest a large number of things - so if it is just a suggestion and you are a professional, do not make a statement on it, while if it is very likely to be, then say that it is likely instead.
That would only explain the clouds in the northern hemisphere.
That would be Aliso Viejo, CA.
"It takes considerable knowledge just to realize the extent of your own ignorance." - Thomas Sowell
It is dangerous to be right when the government is wrong.
I think we're in the late warning category at this point, don't you?
UFOs, they are watching US!!!!!!!!!!!!
Hats off to Russell. The man's been doing solid satellite-based experiments for decades. He's someone you should listen to about climate science.
I can tell you in advance, though, that there's a likely conclusion as to why noctilucent clouds are becoming more prevalent. That is predicted by the global warming simulations. The warmth being radiated from earth is being trapped in the lower atmosphere, and so while it heats up, the upper atmosphere actually cools. That's a solid hypothesis that's already gotten support from the evidence.
(Disclaimer: I'm a distant family member).
hollywood is just generating some advance publicity for their upcoming 2nd x-files movie
in the coming months, they are going to "disappear" some boats in the bermuda triangle and then plant area 51 documents on los alamos national laboratory computers, and then "leak" it
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
. . . a responsible party, like someone working for the Cato Institute, or Exxon-Mobile, or George Deutsch?
In fact, the electrolyte imbalance caused by consuming too much DHMO can kill you, too.
Check out my sci-fi/humor trilogy at PatriotsBooks.
People, I can't believe we're making light of this. We could instead ignore or horribly misinterpret conspicuous evidence, fabricate our own, claim the mainstream is oppressing us out of blindness or malice, and delude ourselves by thinking we're applying skepticism and that others are calling their dogmatic beliefs 'skepticism'!
It's obviously caused by chemicals sprayed from passenger aircraft to control the populace!
http://www.chemtrailcentral.com/
Everything mysterious is caused by the entrenched, all-powerful government's efforts to control every resident human with chemicals.
It's just another glaring piece of proof that everything in the universe is electromagnetic, including stars, comets, and gravity at least plus probably the other two forces as well.
http://www.kronia.com/
Everything mysterious is explained by the entrenched misunderstanding of fundamental science as non-electrical by mainstream academia.
It's just further evidence of alien presence on Earth!
http://www.ufoevidence.org/
Everything mysterious is caused by aliens meddling with and experimenting on humans on our critically important and conspicuous speck of a world.
Come on people! It's time to listen to your fancy and your fear. Stop being rational and skeptical, but still claim you're just being extra-special skeptical. Remember: the other 6 billion humans are just misguided and backward, but your greater intellect saves you from the panic that would grip their feeble minds if they beheld the awesome truth. You'll show them the light because you're just so benevolent, and only you can gently break through to their child-like worlds of fantasy, superstition, and darkness. Truth seekers unite!
Saying "we don't understand everything" isn't the same as saying "we understand nothing". There's plenty we do know about the Earth's atmosphere and climate.
The flash of light you saw in the sky was not a UFO. Swamp gas from a weather balloon was trapped in a thermal pocket and reflected the light from Venus. Now move along.
I've seen these several times over the North Atlantic in the summer.
If you're not paying attention, your first impression is that they look like cirrus clouds viewed from the ground, only much more beautiful.
It's when you remember that you're already 30+ thousand feet up, and that these look like cirrus do when you're on the ground, that you realize how high they are. (That's plain English for 'mesosphere.')
Like satellites, you can see them when your sky is dark but they are catching sunlight due to their altitude.
Right up there with northern lights as a visual treat.
Never shake hands with a man you meet in a fertility clinic.
Hard science, hard fact.
The clouds are caused by space flight, and high flying research planes. We do know, from Paul Newman'ss research, that they seem to appear following shuttle launches, and passing thunderhead clouds. They glow because they are so high in the sky, that the ice crystals are reflecting sunlight, and they are the subject of current research. We also know that they travel to the poles ( about 7k miles from the equator ), in less than 48 hours (Newman), and that they are a component of the catylisys of ozone destruction. (Schindell, Newman, GEOS letters ), but just to be clear about the answer to your question:
"Maybe the cloud is part of a positive feedback cycle that keeps the Earth's climate in acceptable ranges." It is possible that an ELE ( Extinction Level Event ) or ELP ( Extinction Level Process ) will occur, from this reducing Earth's global human population, but the current theory, that Schindell and Newman are proposing, ( they now have 16 years of data ), is that it will lead to a catostrophic loss of ozone for the next 120 years. Their conclusion, not mine, and paid by taxpayer's money.
I mean, after a few hundred million die from carcinoma* (Abarca), we will clearly see, we did the science (with taxpayer funded researchers), we had the proof, and didn't believe it. Tanzania is taking this threat very seriously, and so is Finland.
*Do the math: @Punta Aranus, 177/100,000 die. Nothern Hemisphere expected exposure to ultraviolet B, about 2.6 billion. Will we have the equivlent death rate, or a slightly higher death rate?
Do your self a favor, and hunt down the refrences.
Here are a few links:
http://www.npr.org/templates/story/story.php?storyId=15662891
http://www.sellingcr.com/content/view/54/1/
"Water is a tremendous greenhouse gas. It can condense and form all these clouds. Clouds can reflect radiation. Clouds can actually insulate the surface, if you got a cloud layer overhead the surface stays a little bit warmer. So water is really crucial to the whole process," Newman says.
But, the govenment is not really interested in:
"AEAP: Atmospheric Effects of Aviation Project
The AEAP Project has ended. "
But from other refrences:
http://www.gcrio.org/ocp96/p38box.html
"Water vapor and sulfur oxide concentrations are expected to increase significantly, perhaps as much as 40%, in the stratosphere." ( 1996, again we seem of have lost interest in all this.)
Jeeze...
The Earth's climate has NEVER stopped changing... It has been changing since there was a climate to begin with and it always will, drasticly and massivly. Don't go changing the language to fit the adgenda now, that's completely unscientific. "It may be another sign of the Earth's on-going climate change."
Your welcome.
Contrary to popular belief, coding is not all free blow-jobs and beer. Those things cost MONEY!
These were first seen in the late 1800s around the period that Krakatoa erupted.
I think people underestimate the level of science that was performed then. I'm quite confident that stargazers of the time would indeed notice something new and unseen.
Now it's possible they've appeared in the distant past, gone away and come back, but that's a different story
http://blog.wired.com/defense/2007/12/secret-document.html
They're mooning.
668: Neighbour of the Beast
And why is it only these two Poles get to have special clouds forming over their heads? What, Czechs, Finns, or Canucks aren't good enough?
Impetuous! Homeric!
Will we ever know enough before it's too late? Probably not! Can we do some good things now to give us more time to learn what's going on? Not if everyone has your attitude...
If you continue to analyze until you completely understand everything, the time for effective action is probably long past.
And you propose we do, what... considering we don't know enough to take action. We could affirmatively decide to take inaction, although if we do that, we've taken an action thereby eliminating our objective of inaction. On the other hand, we could pass some laws and crack down on the industrial revolutions of third world countries all the while knowing that we don't know enough to make a responsible decision.
Reading back over this, it really sounds like a flame; it isn't, I just don't understand what you're thinking when you say that we don't know enough to do something, but we must do something if we are to solve a problem we don't understand. Could you elaborate or rephrase your thoughts on this?
*For the record, if it matters, I'm really not for one side or the other in this climate debate. Neither side has adequately convinced me they aren't either zealots or 'on the take'; I'll not hold strong opinions about things I don't understand*
If I mod you up, it doesn't necessarily mean I agree with what you've said, sorry.
Well how about something a little less biased ?
Here's a hint: If your solution to <Problem X> involves global socialism and isn't <people suffering needlessly while resources exist to alleviate it> then you're probably a little too invested in your solution to be trusted about the severity of the problem.
Similarly, if your solution involves reduction of productivity without even attempting to address the problems inherent in the inevitable reduction of available goods, you're probably also going to be ignored.
Can you be Even More Awesome?!
Migor does know these clouds formation are the product of emissions from puny Earth Robots.
You shall have more such clouds unless you produce non-pathetic robots.
Migor will EAT YOUR SOUL
These days, every time I read the news I feel like Beavis, hopped up on pills, yelling such lines as, "I AM THE GREAT CORNHOLIO!" and "WE'RE ALL GONNA DIE!" That's what I get for watching Fox News, and believing the government. From now on, I'm only watching the 700 Club, with their worry free programming (unless you're Hugo Chavez, or Non-American... In which case, I'll pray for you). I'm going to try to recreate the shiny clouds. I'm leaving right now to get some glitter and a pack of cigarettes.
Let's screw up the planet even more to see what other pretty phenomena we can create. I hear oil spills on lakes makes cool rainbow shades in the water.
Table-ized A.I.
Brawndo's got electrolytes!
Dated "06.28.07"
Let me be the first to say 'old news'
"Very little is known about how these clouds form over the poles, why they are being seen more frequently and at lower latitudes than ever before, or why they have been growing brighter."
Should I provide refrences?
These clouds form as a result of water vapor deposited in the stratosphere, by the space shuttle and thunderhead clouds. They travel to the poles rather quickly, and form as clouds, due to the stability of the structure of the polar and antartic vortices. This fact is well known, to Dr. Drew Schindell, and Dr. Paul Newman, ( Dr Newman is still studying these clouds as to their structure ), both scientiests clearly know HOW they form, and Dr Schindell incorporates the stability of the antartic vortex into his ozone destruction models. Your Tax dollars at rest.
They are seen more frequently, due to the increased amount of shuttle launches, and the increased amount of thunder clouds. (DUH!). Due to the increase in the amount of water vapor, at those altitudes, the more clouds, the brighter they are, like water vapor on the ground. On a hot and humid day, with little temprature diffrential, you dont see clouds. On cold and humit days, with a lot of temprature diffrential, you see coulds, they are larger, and brighter. Wilbur and Orville Wright saw this and wrote about it 100 years ago.
"AIM will observe two complete cloud seasons over both poles, documenting an entire life cycle of the shiny clouds for the first time."
Where was this research during 9/11~9/14? When the US aircrafts were grounded? Wouldn't that have an impact on these clouds? Hundreds of scientsts recognised this opportunity, but Aparently Dr Rusell missed it. Best of luck on the experment...
"'It is clear that these clouds are changing, a sign that a part of our atmosphere is changing and we do not understand how, why or what it means,' stated AIM principal investigator James Russell III of Hampton University, Hampton, Va. 'These observations suggest a connection with global change in the lower atmosphere and could represent an early warning that our Earth environment is being changed.'"
Dr. Russell, it means this: "Anyone not wearing sunblock2000 is going to have a real bad day." -Sarah Connor. or...
http://www.coastalpost.com/98/8/10.htm
"There's the same old news about the springtime Antarctic Ozone Hole. It hasn't changed much since the early 1990s because there is almost no ozone left to destroy." -J Scanlon.
Need more refrences, You can use a search engine, or I can, if you want. It only takes a few seconds. Really. Even Dr Russell can do it.
I believe you may be referring to Hydrogen Hydroxide!
Is it time to go home yet?
Skeptics like to cherry pick the year 1998, because it had an exceptionally strong El Nino which raised global temperatures that year; compare to it, the following years don't look as warm. But if you look at the overall trend, the pre-1998 trend has largely continued post-1998. It certainly has not turned negative.
The whole "declining in 2007 to a 1983 level" means that there was some month in 2007 which was the same temperature as some month in 1983. What is relevant, however, is that the temperature trend was positive from 1999-2007.
Even Anthony Watts, the surface temperature skeptic, has contradicted the Telegraph's claims; he said, "On the TLT graph [note: he means the TLS graph], for the years 1998 to present, there appears to be a slight downward trend in lower stratospheric temperature [note: we don't live in the stratosphere; note also that greenhouse warming predicts stratospheric cooling along with tropospheric warming], and this is what I believe Christopher Booker is referencing in his article in the Telegraph. Note that there have been other downward trends in the nearly 30 year measurement history, but the overall trend in the TLT, TMT, and TTS channels has been positive, so a short downward trend doesn't necessarily prove anything." not to mention the newly revised figures for US surface temperatures showing that the 1930s had four of the 10 warmest years of the past century, with the hottest year of all being not 1998, as was previously claimed, but 1934 1998 and 1934 were a statistical tie both before and after the revised figures; the revision is not significant in that regard. We always knew that U.S. temperatures in the 1930s were comparable to the 1990s. This has nothing to do with global warming, however; globally, temperatures in the 1990s were significantly higher than the 1930s. As another poster said, it's become PC to tack on "global warming" to proposals in hopes of getting funding. Oh come on. If you think that you can sneak a shoddy proposal past a grant committee by tacking on an irrelevant reference to global warming, you're incredibly naive.
I've heard these clouds may also contain one or more of the following: Dihydrogen Oxide, Hydrogen Hydroxide, Hydronium Hydroxide, or Hydric acid. Nasty stuff, see http://www.dhmo.org/facts.html for more scary information.
So the NASA satellite snaps a picture of the Arctic region, on June 11, and it's dark there? Shouldn't it be the middle of the arctic day?
And many of the other pictures seem simply to show very high clouds at dusk/dawn, the clouds still/already in sunlight but the ground below already/still in the dark. Is the question about why are the clouds up there, or why they shine?
Yesterday was the time to do it right. Are we having a REVOLUTION yet?
Obviously a sign of Global Cooling...
If I don't put anything here, will anyone recognize me anymore?
The brightness varies quite a bit; sometimes they are rather faint, but at best they're really rather spectacular. Probably related at least to the angle of reflection and the brightness of the background sky.
Here in southern Finland they are rather common sight near late July / early August.
This shot (and others in the same directory) which I took last year is IMO rather close to how they looked to my own eyes:
http://kapsi.fi/~myrjola/photos/digital/tmp/20060713-yopilvet/img_3244-tmp.jpg
The sky is not dark because at that time of year, twilight is as dark as it ever gets.
Everyone who makes generalizations should be shot.
Similar account, other interesting tidbits here