APOD: Light Pillars over Finland (2013 Dec 18)

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Expand view Topic review: APOD: Light Pillars over Finland (2013 Dec 18)

Re: APOD: Light Pillars over Finland (2013 Dec 18)

by Kevin M13 » Sat Dec 21, 2013 6:56 pm

Why draw positive attention to what amounts to light polution? Maybe on the Astronomy NOT picture of the day.

Re: APOD: Light Pillars over Finland (2013 Dec 18)

by topl » Fri Dec 20, 2013 6:46 pm

So happy my photo was chosen, very interesting to read this discussion!
Usually I shoot landscapes and auroras, so I usually do everything I can to avoid light polution and be in a dark spot waiting for Northern lights to appear. I'm no fan of orange clouds, I guess some of you know what I mean :)
I've seen light pillars a few times before but never that strong. There were lamps on houses which had beams as well as any car light, just amazing. Even the moon appeared to have pillars going up and down.
Thanks to those who already explained that the light sources didn't point upwards.

Re: APOD: Light Pillars over Finland (2013 Dec 18)

by Anthony Barreiro » Thu Dec 19, 2013 6:38 pm

owlice wrote:
Anthony Barreiro wrote:Admittedly I don't live in the Arctic, but would somebody please explain to me the difference between light pillars and light pollution? If these parking lot lights were properly shaded to prevent lateral and upward stray light, would they still produce light pillars through ground level ice fog?

Here in San Francisco businesses often promote themselves with searchlights controlled by intentionally distracting computer programs. When the searchlight pattern plays across what I'm looking at in the sky it raises my blood pressure. Why a city that claims to be environmentally concerned allows such a harmful practice is beyond me. Killing the searchlights is one of my new year resolutions.
I think you'll appreciate this:
What a sweet cartoon. Thanks for sharing.

Re: APOD: Light Pillars over Finland (2013 Dec 18)

by Beyond » Thu Dec 19, 2013 6:05 am

owlice wrote:
Beyond wrote:Yeah, nice pillars of light photo and nice widdle puddy tat photo.

I wudda posted this last night, but just after i viewed the puddy tat photo, the Asterisk* went into the 'nothing works' mode, just after 12:40am, and i couldn't get back in by the time i went to bed at 2:20am.
Oh, so YOU'RE the one responsible! I should have known!!
MOI :?: , responsible :?: Isn't that a contradiction of terms :?: :lol2:

Re: APOD: Light Pillars over Finland (2013 Dec 18)

by owlice » Thu Dec 19, 2013 4:55 am

Beyond wrote:Yeah, nice pillars of light photo and nice widdle puddy tat photo.

I wudda posted this last night, but just after i viewed the puddy tat photo, the Asterisk* went into the 'nothing works' mode, just after 12:40am, and i couldn't get back in by the time i went to bed at 2:20am.
Oh, so YOU'RE the one responsible! I should have known!!

Re: APOD: Light Pillars over Finland (2013 Dec 18)

by owlice » Thu Dec 19, 2013 4:49 am

Anthony Barreiro wrote:Admittedly I don't live in the Arctic, but would somebody please explain to me the difference between light pillars and light pollution? If these parking lot lights were properly shaded to prevent lateral and upward stray light, would they still produce light pillars through ground level ice fog?

Here in San Francisco businesses often promote themselves with searchlights controlled by intentionally distracting computer programs. When the searchlight pattern plays across what I'm looking at in the sky it raises my blood pressure. Why a city that claims to be environmentally concerned allows such a harmful practice is beyond me. Killing the searchlights is one of my new year resolutions.
I think you'll appreciate this:

Re: APOD: Light Pillars over Finland (2013 Dec 18)

by jmor62 » Thu Dec 19, 2013 12:54 am

Nice work Mr. Kast!

Re: APOD: Light Pillars over Finland (2013 Dec 18)

by Ron-Astro Pharmacist » Wed Dec 18, 2013 8:18 pm

by Nitpicker » Tue Dec 17, 2013 10:54 pm

Nice. Helps to find your car, too.
Especially if the other guy has his high beams on driving up the hill you're coming down :doh:

Re: APOD: Light Pillars over Finland (2013 Dec 18)

by Anthony Barreiro » Wed Dec 18, 2013 6:49 pm

Chris Peterson wrote:
logmark wrote:Light pillars aren't created as a result of upward-pointing light sources. In fact the pillars aren't really columns of light streaking up from the light sources at all. They are reflections from oriented ice crystals at very oblique angles, meaning they occur between the light source and the eye when looking toward the source, not vertically from it.
Yes, but they still demonstrate poorly shielded lights. There has to be an upwards directed light path from the source in order to produce pillars. It doesn't have to be straight up, but it still has to be higher than good lighting practices dictate.
Thanks to both logmark and Chris for explaining the optics of these light pillars.

Re: APOD: Light Pillars over Finland (2013 Dec 18)

by Anthony Barreiro » Wed Dec 18, 2013 6:48 pm

geckzilla wrote:
Anthony Barreiro wrote:Here in San Francisco businesses often promote themselves with searchlights controlled by intentionally distracting computer programs. When the searchlight pattern plays across what I'm looking at in the sky it raises my blood pressure. Why a city that claims to be environmentally concerned allows such a harmful practice is beyond me. Killing the searchlights is one of my new year resolutions.
I am now imagining you clad in identity-concealing clothing sneaking over to the search lights and throwing bricks into them / spray painting over them / some other form of property destruction with some message attached about the astronomers sending their regards, preferably in old-style newspaper clipping letters. TAkE bACk thE sKY
Sweet. But with all the security video cameras around these days I would probably get caught anyway. I guess I'll have to use the boring old means of convincing my city government to put their high ideals into practice. Seriously, anybody in the SF Bay Area who wants to organize a local chapter of the International Dark Sky Association, please send me a private message.

Re: APOD: Light Pillars over Finland (2013 Dec 18)

by geckzilla » Wed Dec 18, 2013 5:38 pm

Anthony Barreiro wrote:Here in San Francisco businesses often promote themselves with searchlights controlled by intentionally distracting computer programs. When the searchlight pattern plays across what I'm looking at in the sky it raises my blood pressure. Why a city that claims to be environmentally concerned allows such a harmful practice is beyond me. Killing the searchlights is one of my new year resolutions.
I am now imagining you clad in identity-concealing clothing sneaking over to the search lights and throwing bricks into them / spray painting over them / some other form of property destruction with some message attached about the astronomers sending their regards, preferably in old-style newspaper clipping letters. TAkE bACk thE sKY

Re: APOD: Light Pillars over Finland (2013 Dec 18)

by Boomer12k » Wed Dec 18, 2013 4:17 pm

Awesome!!!!!!

:---[===] *

Re: APOD: Light Pillars over Finland (2013 Dec 18)

by Chris Peterson » Wed Dec 18, 2013 4:07 pm

logmark wrote:Light pillars aren't created as a result of upward-pointing light sources. In fact the pillars aren't really columns of light streaking up from the light sources at all. They are reflections from oriented ice crystals at very oblique angles, meaning they occur between the light source and the eye when looking toward the source, not vertically from it.
Yes, but they still demonstrate poorly shielded lights. There has to be an upwards directed light path from the source in order to produce pillars. It doesn't have to be straight up, but it still has to be higher than good lighting practices dictate.

Re: APOD: Light Pillars over Finland (2013 Dec 18)

by logmark » Wed Dec 18, 2013 3:48 pm

Light pillars aren't created as a result of upward-pointing light sources. In fact the pillars aren't really columns of light streaking up from the light sources at all. They are reflections from oriented ice crystals at very oblique angles, meaning they occur between the light source and the eye when looking toward the source, not vertically from it. Shaded street lights create them just as easily as unshaded. The illusion of a column is created as horizontal light beams are reflected from the surface of the very low altitude layer of crystals between the light source and the viewer, and is actually [if it could be pictured from a side view] a shallow, horizontal arc of many thousands of reflecting surfaces over the distance between the eye/camera and the light which only appear to the viewer as a single column. You're not really seeing what you think you're looking at (sort of like politics and kittens :-)

Re: APOD: Light Pillars over Finland (2013 Dec 18)

by Chris Peterson » Wed Dec 18, 2013 3:42 pm

Steve Dutch wrote:There have been folklore claims of ground-level auroras for a long time. Of course, auroras are located high in the atmosphere. But I wonder if a strong auroral display, coupled with ice-pillar conditions, might not create the illusion that the auroras extended to ground level. The ice pillars would reflect the auroras and mimic their changes.
Maybe, but I think it's more likely to just be the result of poor distance perception at night. I get meteor reports all the time where people insist they saw meteors go to the ground less than a mile away, sometimes even when there are intervening mountains. We tend to perceive lights in the sky at night in odd ways.

Re: APOD: Light Pillars over Finland (2013 Dec 18)

by neufer » Wed Dec 18, 2013 3:40 pm

http://astrobob.areavoices.com/?blog=78068 wrote: Ice crystal auroras?
No, just light pillars up to their old tricks
Astrobob, December 17, 2013

<<I knew something was up when I got a Facebook post about a big aurora in the southwestern sky over Duluth last night. Huh? No aurora at my place, so I quickly checked a few aurora sites online. Nothing there either. Ten minutes later I was in the car on my way to pick up my daughter at the airport and it hit me. Light pillars.

Not far from the airport a long bank of snow hid the glare of lights shining from our Air National Guard airbase, but above them rose tall, colorful rays that could have easily been mistaken for the aurora borealis. Ice pillars form on very cold nights when countless ice crystals – often not even noticed with the eye – gently flutter to the ground with the their flat faces parallel to the ground. They reflect the lights below like tiny mirrors to create pillars of spikes of light above bright artificial light sources.

Earlier yesterday evening, a colorful corona circles full moon. Coronae form when light is scattered by minute water droplets in the clouds. Click photo to learn more. Credit: Bob King

I see them most often in approaching car headlights when the glare of the lights is still hidden by a rise in the road. They remind me of antennae. When your car is parked with the lights on, look just ahead of the beams and you’ll see the individual crystals sparking in the light.

As we learned a couple weeks back, winter is the time for all kinds of fascinating light crystal phenomena – halos, sun dogs, arcs, light pillars, coronae and more. All you need to do is look up, something all of you are already very good at doing.>>
http://apod.nasa.gov/apod/ap090112.html
http://asterisk.apod.com/viewtopic.php? ... 19#p100002
http://apod.nasa.gov/apod/ap060305.html

Re: APOD: Light Pillars over Finland (2013 Dec 18)

by Steve Dutch » Wed Dec 18, 2013 3:34 pm

There have been folklore claims of ground-level auroras for a long time. Of course, auroras are located high in the atmosphere. But I wonder if a strong auroral display, coupled with ice-pillar conditions, might not create the illusion that the auroras extended to ground level. The ice pillars would reflect the auroras and mimic their changes.

Re: APOD: Light Pillars over Finland (2013 Dec 18)

by biddie67 » Wed Dec 18, 2013 3:32 pm

I do like a slight deviation on APOD's part from pure astronomical subjects ~~ I finally "got" what these light/sun pillars were all about.

And look at that street lined with those white-barked birch trees. I love them; unfortunately, they aren't a Southern tree ...

Re: APOD: Light Pillars over Finland (2013 Dec 18)

by gcal » Wed Dec 18, 2013 3:01 pm

Interesting picture. But I prefer when APOD sticks to Astronomy. Gimme stars, planets, galaxies, comets...

Re: APOD: Light Pillars over Finland (2013 Dec 18)

by smitty » Wed Dec 18, 2013 3:00 pm

With reluctance and apologies for being a spoil sport and interrupting the flow of talk about cats, I'd just throw in a brief comment about the apod: somebody should talk with those Fins about light pollution! How about installing downward facing street lamps such as those in Tucson Arizona, which were installed out of respect for the neighboring Kitt Peak Observatory. As a sometime amateur astronomer in a large metropolitan area where one can barely see any naked-eye stars even on a clear night I'm perhaps overly sensitive to the issue of light pollution.

Now back to the main thread: how 'bout them cats?! Bet they hate bright lights, too!?

Re: APOD: Light Pillars over Finland (2013 Dec 18)

by Anthony Barreiro » Wed Dec 18, 2013 2:53 pm

Admittedly I don't live in the Arctic, but would somebody please explain to me the difference between light pillars and light pollution? If these parking lot lights were properly shaded to prevent lateral and upward stray light, would they still produce light pillars through ground level ice fog?

Here in San Francisco businesses often promote themselves with searchlights controlled by intentionally distracting computer programs. When the searchlight pattern plays across what I'm looking at in the sky it raises my blood pressure. Why a city that claims to be environmentally concerned allows such a harmful practice is beyond me. Killing the searchlights is one of my new year resolutions.

Re: APOD: Light Pillars over Finland (2013 Dec 18)

by neufer » Wed Dec 18, 2013 1:18 pm

geckzilla wrote:
I'm a little afraid to mention it because I don't want to turn the thread into another cat thread,
but that cat food link is one of the best photos of a kitten. Classic interwebs. ;)
http://www.livescience.com/41984-cats-domesticated-china.html wrote: China Cat? Ancient Chinese May Have Domesticated Felines
By Stephanie Pappas, LiveScience, December 16, 2013

Ancient Chinese villagers may have palled around with felines, according to a new study that finds possible evidence of domesticated cats 5,300 years ago in a Yangshao village.

<<The earliest evidence of cat domestication comes from ancient Egypt, where paintings show kitties getting special treatment. As the sacred animal of the goddess Bast, Egyptian cats were even honored with mummification. Before that, the first evidence of cats and humans interacting is a 9,500-year-old burial on the island of Cyprus, where a wildcat and a person were interred side-by-side. Most of what happened between that burial and the domestication of cats in ancient Egypt remains a mystery. "Despite cats being so beloved as pets, it is surprising how little has been known about their domestication," said study researcher Fiona Marshall, a zoo archaeologist at Washington University in St. Louis.

Domesticated cats were thought to have landed in China only about 2,000 years ago, after the Egyptians exported them to Greece and the felines spread throughout Europe. But new research throws doubt on that theory. The excavation of two ancient refuse pits in the remnants of a Chinese village called Quanhucun in 1997 turned up eight cat bones from at least two separate individuals. Quanhucun was part of the Yangshao culture, a well-studied Neolithic farming culture in China. The bones found include five leg bones, two pelvic bones and one left jawbone. There are two left tibia bones, a find that establishes at least two separate cats were buried there; but because the bones were found at multiple sites, there may have been more. A new analysis of the cat bones, published this week in the journal Proceedings of the National Academy of Sciences, reveals the kitties lived about 5,300 years ago, give or take 200 years. This date makes the remains far older than any known human-associated cat in China.

Whether or not these cats were domesticated is a trickier question to answer. Some evidence points to yes: The bones are smaller than European wildcats and are more comparable in size to European domesticated cats, said Yaowu Hu of the Chinese Academy of Sciences, who led the study. "However, due to the lack of the modern wildcat and domestic cats data, we cannot define them as wild or domesticated just based on the biometric data," Hu told LiveScience. The strongest evidence in favor of domestication, Hu said, comes from the cats' diets. Researchers use molecular variants called isotopes to determine what animals used to eat — the molecules in their diets became the building blocks of their bones. An isotope analysis of both human and animal remains at the village revealed that people ate a diet heavy in the grain millet. Rodents also ate a millet-heavy diet, the researchers found. Cats then ate the rodents, creating a food web that benefited not only the felines, but also the farmers trying to protect their food stores from pets. "It was suspected that cat domestication worked this way," Marshall told LiveScience. "But before this study, there was never any scientific information or proof that it worked that way in the ancient past."

One cat in particular had an unusual diet profile for a meat-eater. Instead of showing high levels of a nitrogen isotope associated with a carnivorous diet, this cat ate a lot of agricultural products. "These data are intriguing, raising the possibility that this cat was unable to hunt and scavenged for discarded human food or that it was looked after and fed by people," the researchers wrote. The research can't, however, explain the spread of domesticated cats. It's possible, Hu said, the Chinese cats were part of the same lineage as the kitties domesticated in Egypt. Or they could have been domesticated in China independently. To solve the mystery, Marshall said, "future work on ancient DNA will be necessary.">>

Re: APOD: Light Pillars over Finland (2013 Dec 18)

by orin stepanek » Wed Dec 18, 2013 12:30 pm

A cool picture on a cool day! 8-)

Re: APOD: Light Pillars over Finland (2013 Dec 18)

by Beyond » Wed Dec 18, 2013 12:19 pm

Yeah, nice pillars of light photo and nice widdle puddy tat photo.

I wudda posted this last night, but just after i viewed the puddy tat photo, the Asterisk* went into the 'nothing works' mode, just after 12:40am, and i couldn't get back in by the time i went to bed at 2:20am.

Re: APOD: Light Pillars over Finland (2013 Dec 18)

by geckzilla » Wed Dec 18, 2013 5:58 am

I'm a little afraid to mention it because I don't want to turn the thread into another cat thread, but that cat food link is one of the best photos of a kitten. Classic interwebs. ;)

PS - I love the light pillars too. A few of these have cropped up at the Flickr feed since winter began in the northern hemisphere. They always have a magical feel to them.

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