Posted on 01/02/2012 9:40:39 PM PST by SunkenCiv
Explanation: Higher than the highest building, higher than the highest mountain, higher than the highest airplane, lies the realm of the aurora. Auroras rarely reach below 60 kilometers, and can range up to 1000 kilometers. Aurora light results from energetic electrons and protons striking molecules in the Earth's atmosphere. Frequently, when viewed from space, a complete aurora will appear as a circle around one of the Earth's magnetic poles. The above wide angle image, horizontally compressed, captured an unexpected auroral display that stretched across the sky one month ago over eastern Norway.
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[Credit & Copyright: Sebastian Voltmer]
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Thanks for posting this fantastic, fabulous picture!
Amid all the news about holiday killings, political mud slinging and accusations, and dire predictions about 2012, your photo is a welcome respite, a true thing of beauty!!
Truly a nice way to end my evening.
Awesome!
bttt
Highly distorted and compressed horizontally. Stretch it out about twice its width.
You would never see that display for real, although North Norway has the best and most consistent aurora displays.
Just gorgeous!
God tripped carrying paint to the shed.
So much green, I’m surprised! Beautiful!
Oxygen is unusual in terms of its return to ground state: it can take 3/4 sec to emit green light and up to two minutes to emit red. Collisions with other atoms or molecules will absorb the excitation energy and prevent emission. Because the very top of the atmosphere has a higher percentage of oxygen and is sparsely distributed such collisions are rare enough to allow time for oxygen to emit red. Collisions become more frequent progressing down into the atmosphere, so that red emissions do not have time to happen, and eventually even green light emissions are prevented.
- oxygen Green or brownish-red, depending on the amount of energy absorbed.
- nitrogen Blue or red. Blue if the atom regains an electron after it has been ionized. Red if returning to ground state from an excited state.
This is why there is a colour differential with altitude; at high altitude oxygen - red - dominates, then oxygen - green - and nitrogen - blue/red - finally nitrogen: blue/red (collisions prevent oxygen from emitting anything).
Green is the most common color of all auroras. Behind it is pink, a mixture of light green and red, followed by pure red, yellow (a mixture of red and green), and lastly pure blue.
Thank you very much, dear raygun! I think I’ll bookmark this thread right now to save your information so that I can refer back to it. Very much appreciated!!
Thank you, SunkenCiv! You know how much I love looking at pictures of the Aurora. It is just so mystical and magical. (now I feel bad... I didn’t get you anything).
To SunkerCiv: Beautiful, but at the same time scary. I know this is silly, but it reminds me of a ‘wall cloud,’ which here in Texas is associated with violent thunderstorms and tornados.
To raygun: Your comment brought back memories. In graudate school, I wrote a paper on the Aurora for an astronomy class. References to the solar wind, magnetosphere etc. all jogged my old memory. I got an “A” on the paper and in the class. (”It ain’t braggin’ if you can do it.”)
The last one was all pixel-y anyway. This is much better.
You Made My Day.
Spectacular
I thought the aurora would be less spectacular with the low number of sunspots. Maybe not. Gorgeous!
WOW!
:’D
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