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APOD: Cloudy Night of the Northern Lights (2011 Sep 30)

Posted: Fri Sep 30, 2011 4:06 am
by APOD Robot
Image Cloudy Night of the Northern Lights

Explanation: On September 26, a large solar coronal mass ejection smacked into planet Earth's magnetosphere producing a severe geomagnetic storm and wide spread auroras. Captured here near local midnight from Kvaløya island outside Tromsø in northern Norway, the intense auroral glow was framed by parting rain clouds. Tinted orange, the clouds are also in silhouette as the tops of the colorful shimmering curtains of northern lights extend well over 100 kilometers above the ground. Though the auroral rays are parallel, perspective makes them appear to radiate from a vanishing point at the zenith. Near the bottom of the scene, an even more distant Pleiades star cluster and bright planet Jupiter shine on this cloudy northern night.

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Re: APOD: Cloudy Night of the Northern Lights (2011 Sep 30)

Posted: Fri Sep 30, 2011 4:11 am
by owlice
WOW!!!

Re: APOD: Cloudy Night of the Northern Lights (2011 Sep 30)

Posted: Fri Sep 30, 2011 4:15 am
by Beyond
WOWEE!!

Re: APOD: Cloudy Night of the Northern Lights (2011 Sep 30)

Posted: Fri Sep 30, 2011 7:00 am
by starstruck
The interplay of the radiating lines of green, purple and magenta, with the orange under-lit clouds makes this, for me, a truly arresting photo! Having a few clouds in the picture, together with the stars shining through, gives it great scale and depth. To think that this is a naturally occurring spectacle in the sky; just amazing! I would dearly love to see this dramatic phenomenon with my own eyes some day. Congratulations to the photographer, Fredrik Broms. The link to the photographer's website is well worth viewing too . . more of the aurorae and other astro pictures, as well as some stunning wildlife and landscape photos. Bravo!

Re: APOD: Cloudy Night of the Northern Lights (2011 Sep 30)

Posted: Fri Sep 30, 2011 8:43 am
by mtbdudex
Beautiful and inspiring, great job Mr. Fredrick Broms.

Re: APOD: Cloudy Night of the Northern Lights (2011 Sep 30)

Posted: Fri Sep 30, 2011 12:48 pm
by orin stepanek
owlice wrote:WOW!!!
Beyond wrote:WOWEE!!
Wow; Wowee; is right; Looks like an artist really got going on a canvas! 8-) 8-) :D

Re: APOD: Cloudy Night of the Northern Lights (2011 Sep 30)

Posted: Fri Sep 30, 2011 3:02 pm
by Guest
I like the depth scale hinted by the caption. Suppose the rain clouds are 1KM away. Then the aurora is 100 TIMES farther than the clouds. Jupiter is 6 MILLION TIMES farther than the aurora. The Pleiades are 6 MILLION TIMES farther than Jupiter. That's a lot of depth!

Re: APOD: Cloudy Night of the Northern Lights (2011 Sep 30)

Posted: Fri Sep 30, 2011 3:31 pm
by NoelC
As one who has never personally seen this phenomenon, I can only say I would be dumbstruck if I were to look up and see something like that. It would be especially disconcerting that it seems to be centered on a position straight up from the observer's viewpoint.

The caption mentions "severe geomagnetic storm"... Does the use of the term "severe" indicate danger to people? Radiation levels higher than normal? Electrical systems taking surges? Stay in bed under a lead blanket?

-Noel

Re: APOD: Cloudy Night of the Northern Lights (2011 Sep 30)

Posted: Fri Sep 30, 2011 3:59 pm
by Chris Peterson
NoelC wrote:As one who has never personally seen this phenomenon, I can only say I would be dumbstruck if I were to look up and see something like that. It would be especially disconcerting that it seems to be centered on a position straight up from the observer's viewpoint.
Keep in mind that this is a photographic view: brightness and especially color saturation are enhanced over a visual view. That may not be as obvious with the aurora, which many people don't have much practical familiarity with, but should be apparent with the light-pollution illuminated clouds, which most people see all the time.
The caption mentions "severe geomagnetic storm"... Does the use of the term "severe" indicate danger to people? Radiation levels higher than normal? Electrical systems taking surges? Stay in bed under a lead blanket?
No geomagnetic storm poses any health risks to people on the surface of the Earth. Solar activity is graded, and the terms apply to the sort of coincident energy that might be coupled into the power grid, or impact space-based assets.

Re: APOD: Cloudy Night of the Northern Lights (2011 Sep 30)

Posted: Fri Sep 30, 2011 4:01 pm
by rstevenson
NoelC wrote:As one who has never personally seen this phenomenon, I can only say I would be dumbstruck if I were to look up and see something like that.
That was my reaction the first time I saw a really good aurora, while I was visiting Dawson City in the Yukon. I stood there staring up, slack-jawed, for a good 30 minutes until my neck protested mightily. Luckily it was winter so my mouth didn't fill with insects.

Rob

Re: APOD: Cloudy Night of the Northern Lights (2011 Sep 30)

Posted: Fri Sep 30, 2011 6:53 pm
by NoelC
Chris Peterson wrote:should be apparent with the light-pollution illuminated clouds, which most people see all the time.
Heh, I live in Bortle level 1 light pollution. Clouds really DO look that bright here. Only reason we're level 1 is that there's not a level 0.

-Noel

Re: APOD: Cloudy Night of the Northern Lights (2011 Sep 30)

Posted: Fri Sep 30, 2011 8:09 pm
by Chris Peterson
NoelC wrote:
Chris Peterson wrote:should be apparent with the light-pollution illuminated clouds, which most people see all the time.
Heh, I live in Bortle level 1 light pollution. Clouds really DO look that bright here. Only reason we're level 1 is that there's not a level 0.
Bright, maybe, but I don't believe they appear that color to the eye!

Re: APOD: Cloudy Night of the Northern Lights (2011 Sep 30)

Posted: Fri Sep 30, 2011 8:18 pm
by NoelC
Well, maybe not *quite* so orange, but definitely warm colored. Yes, I understand that things have been done to the image to make it more brightly colored.

Some time ago I took two photos - one before a hurricane and one after (when the power infrastructure had been knocked out). What a world of difference!

Image

Somewhere around here I have a photo of the south Florida night sky showing how the LP exceeds even the glow from a full moon... I'll see if I can find it, because I think it had some clouds in it.

-Noel

Re: APOD: Cloudy Night of the Northern Lights (2011 Sep 30)

Posted: Mon Oct 03, 2011 2:16 pm
by noctiluca
"Severe geomagnetic storm" does not pose any threat to us (so no need to hide under a blanket :D), but for displays as strong as this one, some problems might occur for spacecraft operations, satellite components and there might be radio navigation problems on Earth aso.. Better to get out of the blanket and look at the sky!

When it comes to the colour in the picture, I actually had to go down quite a bit on saturation to get the colours correct, normally we see mostly "oxygen-green" auroras, but during this storm the purple and red hues were dominating (and the colours in the picture is close to what could be seen with the naked eye). The coronas moved so quickly I couldn`t believe my eyes - normally time-lapse sequences and the like are a bit unrealistically speeded up, but for this display even the most up-speeded video sequences I have seen doesn`t do it justice.., it has to be seen to be believed and no pictures or words can really describe it.

I wish clear and dark skies to all of you, who knows how far south the next CME might be seen !?

Kind regards, Fredrik Broms

Re: APOD: Cloudy Night of the Northern Lights (2011 Sep 30)

Posted: Mon Oct 03, 2011 7:41 pm
by alter-ego
Chris Peterson wrote:
NoelC wrote:As one who has never personally seen this phenomenon, I can only say I would be dumbstruck if I were to look up and see something like that. It would be especially disconcerting that it seems to be centered on a position straight up from the observer's viewpoint.
Keep in mind that this is a photographic view: brightness and especially color saturation are enhanced over a visual view. That may not be as obvious with the aurora, which many people don't have much practical familiarity with, but should be apparent with the light-pollution illuminated clouds, which most people see all the time.
rstevenson wrote:
NoelC wrote:As one who has never personally seen this phenomenon, I can only say I would be dumbstruck if I were to look up and see something like that.
That was my reaction the first time I saw a really good aurora, while I was visiting Dawson City in the Yukon. I stood there staring up, slack-jawed, for a good 30 minutes until my neck protested mightily. Luckily it was winter so my mouth didn't fill with insects.
noctiluca wrote:When it comes to the colour in the picture, I actually had to go down quite a bit on saturation to get the colours correct, normally we see mostly "oxygen-green" auroras, but during this storm the purple and red hues were dominating (and the colours in the picture is close to what could be seen with the naked eye). The coronas moved so quickly I couldn`t believe my eyes - normally time-lapse sequences and the like are a bit unrealistically speeded up, but for this display even the most up-speeded video sequences I have seen doesn`t do it justice.., it has to be seen to be believed and no pictures or words can really describe it.

I wish clear and dark skies to all of you, who knows how far south the next CME might be seen !?

Kind regards, Fredrik Broms
I've seen one grand coronal aurora here in Washington, and I witnessed an extremely dynamic phenomena that I've never heard of or seen documented before.
In Nov 2004, my excitement escalated quickly when I saw web-site auroral activity was very high, AND I new the sky was clear, AND it was near midnight. A perfect storm! I went ouside and looked up only to first be disappointed by a large area of cloud-covered sky, lit up I thought by Seattle!! But then as my eyes adjusted to the darkness I was amazed to see a huge aurora at my zenith, rays dancing about and merging, all converging to a (vanashing) point overhead. This was amazing. Visual colors were not apparent at first, but just as the POD shows redish and purplish patches, I did see those colors by eye in a small region lower in the sky. This aurora was long lasting, I'm guessing an hour. But that jaw-dropping behavior I saw I can only describe as annulus waves light, centered on the vanishing point, that propagated toward or away (I can't remember) from this point at maybe 5 times per second over the whole auroral display! The width of these annulus (donut) waves were several degrees at most. I've seen auroal pillars come and go, dancing rays, and lovely curtains waving like a flag in the wind, all at on time scales of 10's of seconds to minutes, but I've never seen these bright, concentric waves of light propagating over 45°radius in 1/10 sec or so, and repetitively at 5Hz!

I'm certainly interested if anyone has seen this or other less common aroral behavior.