Scientists Find the Trigger of the Northern Lights

[hyphenate]

By KENNETH CHANG
Published: July 25, 2008
http://www.nytimes.com/2008/07/25/science/space/25aurora.html?hp

Scientists say they have discovered what makes the northern lights dance.


M. Scott Moon/Associated Press

The aurora borealis as seen from Denali National Park in Alaska in 2006.

Researchers working on a NASA mission to understand the interplay of magnetic fields and charged particles blown outward from the Sun have identified the trigger for the colorful electrical storms in the polar regions. They hope this is a step in developing reliable forecasts of geomagnetic storms that can disrupt satellites in orbit and power grids on the ground.

The findings appeared in an article published Thursday on the Web site of the journal Science.

Scientists have long known that the dancing auroras of color known as the northern and southern lights are generated by charged particles flying from the Sun and interacting with the Earth’s magnetic field, which is then pulled into a windsock shape by the solar wind.

Turbulent storms on the Sun generate extremely bright auroral displays, but even in quieter times, smaller events known as substorms still generate the lights.

“They happen every three or four hours,” said Vassilis Angelopoulos, a professor of earth and space sciences at University of California, Los Angeles, and principal investigator of a NASA mission called Themis, short for Time, History of Events and Macroscale Interactions during Substorms. “The Earth’s environment stores energy. Then all of a sudden it releases it.”

Each substorm generates a current of about one million to two million amps over one to two hours, or a total energy equivalent to a magnitude-5 or magnitude-6 earthquake, Dr. Angelopoulos said.

[Straight Shooter]

1. I have only seen them once, and they are spectacularly beautiful and eerie.

Thanks for sharing.

[hyphenate]

3. We used to see them

when we'd go to my grandparents' farm in Cape Breton when I was young. Of course, the air was clearer back then, with very little development, and we kind of took them for granted. I haven't been up now in almost 20 years, but I doubt if I could take anything like that for granted anymore.

[roguevalley]

14. we see them when the air is clear and cold. I've seen them move

and change color. the prettiest ones were white shimmering curtains with a gold glowing trim along the bottom. I even heard them. a faint groaning sound. it has to be damned cold when that happens. I think it was about -35 when I heard that out in the country going to my sister's house.

RV, in AK

[Breeze54]

2. Interesting! I saw them down as far as MA a couple of years ago and it was so beautiful!

The Aurora Borealis over SW Massachusetts. - 2007?

http://winchester.smugmug.com/gallery/1259043_zJGuC/3/117088290_avGLp#117088290_avGLp

Location: Cape Cod Imaging Station. East Dennis, Massachusetts-2002

http://www.abmedia.com/astro/aurora/aurora-18-090702.html

K&R

[femrap]

4. Google Maurice Cotterell

who believes everything comes from the Sun...he may be right.

[ClayZ]

5. I saw them when we went to the Talkeetna Bluegrass Festival

I will never forget how beautiful they were!

Great Festival!

[Blue_In_AK]

9. When did you go?

Back in the old days, the Talkeetna Bluegrass Festival was free, unpublicized, and they moved it from place to place each year (always somewhere in the vicinity of Talkeetna, though), so it was always kind of a secret for the "in the know" crowd. That's when it used to be really fun. It's still a good time, but lost some of the mystique once they started charging admission and having it in a set place each year.

[ClayZ]

21. We went in 1992.... (I think) heh heh*

"The Frozen Few" were the security guards and their black tee-shirts said "Karma Control".

We helped our neighbors (vendors) build their temporary "Love Burgers" restaurant.

We seriously met a GREAT bunch of people there!

I love Alaska!

[Blue_In_AK]

23. Thank you, Clay.

I love Alaska, too, and it sounds like you definitely got into the spirit of Talkeetna. Talkeetna and Homer are my favorite little towns here.

[Arugula Latte]

6. Whaaa? You mean it's NOT Jebus turnin' on the lava lamp?

:o

[conscious evolution]

7. I want that job

I think I would be really good at making a career out of watching the Auroras.

Think they are hiring?

I sure hope I get a chance to see them some day.

[Cleita]

8. The first time I saw them was in the middle of rural Kansas.

None of us who witnessed them knew what they were. The news later that night told us. The second time I saw them, more appropriately, was on an airplane as we were getting ready to land in Fairbanks, Alaska. They are magical because unlike clouds and thunderstorms most of us find them exotic.

[Ghost in the Machine]

10. My trigger is usually around the third toke...

That 'Northern Lights' is some killer bud, man... a little costly, but well worth it overall. Pungent aroma and nice smooth taste....

Huh? .... Lights in the sky? Well yeah, it make you see lights in the sky if ya smoke too much.... Aurora who? Is that the funny little guy that lives over by the park? I don't know his real name..

What? Whaddya mean Northern Lights ain't weed?

[MaybeSo]

11. That A Joke? n/t

[roguevalley]

15. snerk. you belong in Alaska. :-D

[Blue_In_AK]

24. Ha, that's what I thought, too, Rogue.

Ghost would fit right in.

[iamthebandfanman]

16. lol

i must be a pothead... the first thing i think of when i hear 'northern lights' is marijuana.

sad sad sad.
lol

[MaybeSo]

12. Call Me Ignorant....

But I had no idea that they hadn't already figured those things out! I've never seen them, but I've always wanted to. They look breath- taking, and I bet I could get some B.E.A.U.tiful pics. of them.

[LanternWaste]

19. I've never seen them myself.

I've never seen them myself-- too far south and rarely get north of the TX panhandle anymore. <sigh>. One day though... one day :)

[Kitty Herder]

13. One of the most beautiful phenomena on the planet.

I lived in Fairbanks, AK for a while and the aurora almost made the winter bearable.

I remember one night in particular, they were so spectacular that I literally fell to my knees in the snow in worshipful awe. Ribbons of green, fushia and white were streaming across the entire sky like beautiful wraiths, celestial spirits.

If you've never seen them, it's worth a trip to Alaska in the winter.

[exothermic]

18. I've been lucky to see them -and- the Southern variety too!

(from southern Chile...I failed to grab the opportunity to go on to Antarctica and kick my own ass frequently)

[shadowknows69]

17. I've seen really amazing northern lights a couple times

Just mesmerizing

[struggle4progress]

20. I saw these at Guadalupe Mountain Park in West Texas

http://apod.nasa.gov.nyud.net:8090/apod/image/0009/aurtex_grohusko.jpg

<edit: not my pic: from NASA> http://apod.nasa.gov/apod/ap000915.html

[Judi Lynn]

22. Photo of an aurora taken from space, with added image of satellite:

An artist's concept of the FAST satellite superimposed on a photo of the aurora taken from the space shuttle. Credit: NASA
Durable Spacecraft Marks 10 Years Exploring Processes That Create the Aurora
http://www.nasa.gov/vision/universe/solarsystem/fast_10yr.html



aurora above Jupiter, recorded by satellite
Satellite Footprints Seen in Jupiter Aurora
http://hubblesite.org/newscenter/archive/releases/2000/38