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APOD: Ash and Lightning Above an Icelandic... (2010 Apr 19)

Posted: Mon Apr 19, 2010 3:52 am
by APOD Robot
Image Ash and Lightning Above an Icelandic Volcano

Explanation: Why did the recent volcanic eruption in Iceland create so much ash? Although the large ash plume was not unparalleled in its abundance, its location was particularly noticeable because it drifted across such well populated areas. The Eyjafjallajökull volcano in southern Iceland began erupting on March 20, with a second eruption starting under the center of small glacier on April 14. Neither eruption was unusually powerful. The second eruption, however, melted a large amount of glacial ice which then cooled and fragmented lava into gritty glass particles that were carried up with the rising volcanic plume. Pictured above two days ago, lightning bolts illuminate ash pouring out of the Eyjafjallajökull volcano.

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Re: APOD: Ash and Lightning Above an Icelandic... (2010 Apr

Posted: Mon Apr 19, 2010 4:15 am
by owlice
What a great picture that is!

Re: APOD: Ash and Lightning Above an Icelandic... (2010 Apr

Posted: Mon Apr 19, 2010 4:26 am
by Astronut
Now thats HOT STUFF !!!! - COOL !

Re: APOD: Ash and Lightning Above an Icelandic... (2010 Apr

Posted: Mon Apr 19, 2010 4:53 am
by KJackson
Great picture but I am curious as to how it was taken. It looks like it is shot from above looking down on the volcano - could it be taken from a plane?

Re: APOD: Ash and Lightning Above an Icelandic... (2010 Apr

Posted: Mon Apr 19, 2010 6:01 am
by Amir
KJackson wrote:It looks like it is shot from above looking down on the volcano - could it be taken from a plane?
to me it looks like it's been taken from side, from a higher point in the mountain.
the smoke is going up, what makes you think it is looking down?

Re: APOD: Ash and Lightning Above an Icelandic... (2010 Apr

Posted: Mon Apr 19, 2010 6:48 am
by bystander

Re: APOD: Ash and Lightning Above an Icelandic... (2010 Apr

Posted: Mon Apr 19, 2010 7:40 am
by bruno

Re: APOD: Ash and Lightning Above an Icelandic... (2010 Apr

Posted: Mon Apr 19, 2010 9:38 am
by ES.E
Impressive indeed.
There is something i do no t quite understand: there seem to be long star trails.
How is that possible? What is the exposure time? How come at least one of the trails is in front of the ash?

Re: APOD: Ash and Lightning Above an Icelandic... (2010 Apr

Posted: Mon Apr 19, 2010 9:56 am
by wonderboy
KJackson wrote:Great picture but I am curious as to how it was taken. It looks like it is shot from above looking down on the volcano - could it be taken from a plane?

How ironic would it be if it was taken from a plane? haha.

Scary photo though, It looks like the earth is giving birth to the anti christ or something.

More proof that the world is FUBAR? I think so.

Re: APOD: Ash and Lightning Above an Icelandic... (2010 Apr

Posted: Mon Apr 19, 2010 11:13 am
by rstevenson
ES.E wrote:Impressive indeed.
There is something i do no t quite understand: there seem to be long star trails.
How is that possible? What is the exposure time? How come at least one of the trails is in front of the ash?
I don't know the exposure time, but it's not surprising that a star trail is "in front of" the ash. The star trail was created over a period of time. During that time the ash cloud was moving and changing. Then a lightning flash occurred which illuminated the ash cloud when it was in a particular position where a small portion of it was over top of the star trail. The cloud may have obscurred where the star was to a local observer, but the star trail had already been exposed onto the film. Or would be exposed onto the film after the lightning flash occurred and the cloud shifted away. Either way, no mystery.

Rob

Re: APOD: Ash and Lightning Above an Icelandic... (2010 Apr

Posted: Mon Apr 19, 2010 11:16 am
by rstevenson
wonderboy wrote:Scary photo though, It looks like the earth is giving birth to the anti christ or something.
More proof that the world is FUBAR? I think so.
Eruptions, ash clouds and lightning are normal natural processes of the Earth, that are occurring somewhere on the globe at almost all times. So why do you think this particular eruption is evidence that the world is FUBAR?

Rob

Re: APOD: Ash and Lightning Above an Icelandic... (2010 Apr

Posted: Mon Apr 19, 2010 11:54 am
by neufer
wonderboy wrote:
KJackson wrote:Great picture but I am curious as to how it was taken. It looks like it is shot from above looking down on the volcano - could it be taken from a plane?
How ironic would it be if it was taken from a plane? haha.
A prop plane not downwind of the plume.
wonderboy wrote:Scary photo though, It looks like the earth is giving birth to the anti christ or something.
Waiting for the Stajpuft Marshmallow Man
Image

Re: APOD: Ash and Lightning Above an Icelandic... (2010 Apr

Posted: Mon Apr 19, 2010 1:11 pm
by wonderboy
Not just this eruption. There has been an increase in natural disasters. We're coming into hurricane season (are we not) that will be a telling point. Theres been tremors under dormant volcanos, earthquakes killing thousands, tsunamis killing hundreds of thousands. I think Earth is giving us a ticking off and mothers know best, so we should all listen to mother nature or on our heads be it.

Re: APOD: Ash and Lightning Above an Icelandic... (2010 Apr

Posted: Mon Apr 19, 2010 1:20 pm
by orin stepanek
Today's photo is awesome. The billowing ash cloud; the hot lava; the lightning; the picture has everything. The world is a restless world; constantly changing its geometry. Keeps life interesting and map makers busy. 8-) :lol:

Re: APOD: Ash and Lightning Above an Icelandic... (2010 Apr

Posted: Mon Apr 19, 2010 2:03 pm
by Chris Peterson
wonderboy wrote:Not just this eruption. There has been an increase in natural disasters. We're coming into hurricane season (are we not) that will be a telling point. Theres been tremors under dormant volcanos, earthquakes killing thousands, tsunamis killing hundreds of thousands. I think Earth is giving us a ticking off and mothers know best, so we should all listen to mother nature or on our heads be it.
I don't notice that there has been any increase in natural disasters. Like anything with a random distribution, you see events in clumps and quiet periods. If anything, it seems like natural disaster activity has been a little on the low side the last few years.

Re: APOD: Ash and Lightning Above an Icelandic... (2010 Apr

Posted: Mon Apr 19, 2010 2:37 pm
by bystander
neufer wrote:A prop plane not downwind of the plume.
So you think internal combustion engines are not affected? The Mount Saint Helens and Mount Penatubo experiences would seem to disparage that. However, the not downwind would probably keep you out of trouble.

Re: APOD: Ash and Lightning Above an Icelandic... (2010 Apr

Posted: Mon Apr 19, 2010 2:40 pm
by RJN
Caption Contest: "Upon seeing Mordor first hand, Frodo decided to pawn the One ring on a nearby street corner."

Re: APOD: Ash and Lightning Above an Icelandic... (2010 Apr

Posted: Mon Apr 19, 2010 2:51 pm
by bystander
RJN wrote:Caption Contest: "Upon seeing Mordor first hand, Frodo decided to pawn the One ring on a nearby street corner."
:lol:

Re: APOD: Ash and Lightning Above an Icelandic... (2010 Apr

Posted: Mon Apr 19, 2010 3:41 pm
by biddie67
The photographer, Marco Fulle, was just interviewed on Fox News cable TV station. He's a scientist and is planning on going back out for another survey and more pictures. The station will be recycling the interview (by phone) a couple times each hour.

P.S. the same picture as this APOD was shown on the TV screen.

Re: APOD: Ash and Lightning Above an Icelandic... (2010 Apr

Posted: Mon Apr 19, 2010 4:04 pm
by Minkyboodle
I still do not understand the timing of the photo. How can star trails be visible, and yet the ash cloud be in focus and not caught in rolling movement? Seems to me that it should have the same affect as taking a time-lapse photo of a waterfall. From the length of the trails, it could have been a half hour exposure, and yet the cloud hardly moves in that time period?

Re: APOD: Ash and Lightning Above an Icelandic... (2010 Apr

Posted: Mon Apr 19, 2010 4:07 pm
by minkyboodle
Minkyboodle wrote:I still do not understand the timing of the photo. How can star trails be visible, and yet the ash cloud be in focus and not caught in rolling movement? Seems to me that it should have the same affect as taking a time-lapse photo of a waterfall. From the length of the trails, it could have been a half hour exposure, and yet the cloud hardly moves in that time period?
Nevermind...my brain finally kicked in. The flash of lightening froze the position of the cloud in the exposure, writing the image over the darker and more fluid image of the cloud, thus, a terrific picture that this dope understands.

Re: APOD: Ash and Lightning Above an Icelandic... (2010 Apr

Posted: Mon Apr 19, 2010 5:08 pm
by BMAONE23
rstevenson wrote:
ES.E wrote:Impressive indeed.
There is something i do no t quite understand: there seem to be long star trails.
How is that possible? What is the exposure time? How come at least one of the trails is in front of the ash?
I don't know the exposure time, but it's not surprising that a star trail is "in front of" the ash. The star trail was created over a period of time. During that time the ash cloud was moving and changing. Then a lightning flash occurred which illuminated the ash cloud when it was in a particular position where a small portion of it was over top of the star trail. The cloud may have obscurred where the star was to a local observer, but the star trail had already been exposed onto the film. Or would be exposed onto the film after the lightning flash occurred and the cloud shifted away. Either way, no mystery.

Rob
Looking close, I see about 10 separate star trails

Re: APOD: Ash and Lightning Above an Icelandic... (2010 Apr

Posted: Mon Apr 19, 2010 6:30 pm
by RKO
Very nice picture. How does it relate to astronomy?

Re: APOD: Ash and Lightning Above an Icelandic... (2010 Apr

Posted: Mon Apr 19, 2010 6:40 pm
by owlice
RKO wrote:Very nice picture. How does it relate to astronomy?
It shows the eruption of a volcano on one of the planets in our solar system.

Re: APOD: Ash and Lightning Above an Icelandic... (2010 Apr

Posted: Mon Apr 19, 2010 7:10 pm
by DennyMo
The question everyone I've shown the picture to is "Why is the lightning purple?" Any good answers to that one for me? Artifact of photography, spectral emissions of the lightning affected by the composition of the ash, other?