APOD: Spiral Aurora over Icelandic Divide (2019 Apr 21)

[APOD Robot]

Spiral Aurora over Icelandic Divide

Explanation: Admire the beauty but fear the beast. The beauty is the aurora overhead, here taking the form of great green spiral, seen between picturesque clouds with the bright Moon to the side and stars in the background. The beast is the wave of charged particles that creates the aurora but might, one day, impair civilization. In 1859, following notable auroras seen all across the globe, a pulse of charged particles from a coronal mass ejection (CME) associated with a solar flare impacted Earth's magnetosphere so forcefully that they created the Carrington Event. A relatively direct path between the Sun and the Earth might have been cleared by a preceding CME. What is sure is that the Carrington Event compressed the Earth's magnetic field so violently that currents were created in telegraph wires so great that many wires sparked and gave telegraph operators shocks. Were a Carrington-class event to impact the Earth today, speculation holds that damage might occur to global power grids and electronics on a scale never yet experienced. The featured aurora was imaged in 2016 over Thingvallavatn Lake in Iceland, a lake that partly fills a fault that divides Earth's large Eurasian and North American tectonic plates.

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[Boomer12k]

A crazy "@" symbol with a TAIL!!

Awesome.

:---[===] *

[Ann]

A crazy "@" symbol with a TAIL!!

Awesome.

:---[===] *

Ann

[orin stepanek]

Nice Photo of a strange phenomenon! (IMO) Do you suppose that resulted from a spiral flare?

[AlbireoA]

This picture was already used on 2016 August 30...

[NHcycler]

This picture was already used on 2016 August 30...

Your point is??

Reminiscent of the Tadpole Galaxy APOD of a few days ago!

[E Fish]

Aren't Sunday images always repeats?

That is a gorgeous image, though. And a nice combination of astronomy and geology, two of my favorite sciences!

[BDanielMayfield]

Were a Carrington-class event to impact the Earth today, speculation holds that damage might occur to global power grids and electronics on a scale never yet experienced.

Then it's fortunate that we appear to heading into a period of low sunspot activity. The downside is that aurora's would become much rarer.

Bruce

[Chris Peterson]

Were a Carrington-class event to impact the Earth today, speculation holds that damage might occur to global power grids and electronics on a scale never yet experienced.

Then it's fortunate that we appear to heading into a period of low sunspot activity. The downside is that aurora's would become much rarer.

Auroras remain quite common even when the Sun is very inactive. But they are far less likely to move outside of high latitudes, so the likelihood of seeing them for most people is much smaller.

[BDanielMayfield]

Were a Carrington-class event to impact the Earth today, speculation holds that damage might occur to global power grids and electronics on a scale never yet experienced.

Then it's fortunate that we appear to heading into a period of low sunspot activity. The downside is that aurora's would become much rarer.

Auroras remain quite common even when the Sun is very inactive. But they are far less likely to move outside of high latitudes, so the likelihood of seeing them for most people is much smaller.

I now live at about 43deg 58' north, but didn't move far enough, apparently.

[Chris Peterson]

Then it's fortunate that we appear to heading into a period of low sunspot activity. The downside is that aurora's would become much rarer.

Auroras remain quite common even when the Sun is very inactive. But they are far less likely to move outside of high latitudes, so the likelihood of seeing them for most people is much smaller.

I now live at about 43deg 58' north, but didn't move far enough, apparently.

Or south.

[orin stepanek]

Aren't Sunday images always repeats?

That is a gorgeous image, though. And a nice combination of astronomy and geology, two of my favorite sciences!

Almost always! OTTO needs a day off once in a while also!

[dlw]

Might that red streak reflected on the lake be a meteor from behind the clouds?

[ems57fcva]

Nice aurora. But I have a few quibbles about the caption.

1) The water in the picture appears to be a moving stream, not a lake. And that water looks to me to be no more than a few hundred feet wide at most, while Thingvallavatn Lake covers an area of 32 square miles. I have been at that lake, and even from a the cliffs near its northern shore you cannot see the southern shore.

2) What Thingvallavatn Lake partially fills is not a fault but a rfit valley. This is because the North American and Eurasian plates are pulling apart there instead of sliding past each other. (Also, the east side of Thingvallavatn actually belongs to a microplate and the Eurasian plate begins at another rift valley over 50 miles east of there. But that is subtle detail and is almost not worth mentioning.)

[alter-ego]

Might that red streak reflected on the lake be a meteor from behind the clouds?

It is possible. The streak coincidentally is short enough and apparently in the right position to be hidden by the cloud that's partially covering Taurus, coincidentally pointing near the Perseid radiant, and is coincidental with the nominal shower duration. The image is dated Aug 24.
 

[Joe Stieber]

Might that red streak reflected on the lake be a meteor from behind the clouds?

It is possible. The streak coincidentally is short enough and apparently in the right position to be hidden by the cloud that's partially covering Taurus, coincidentally pointing near the Perseid radiant, and is coincidental with the nominal shower duration. The image is dated Aug 24.

I’d be inclined to think that it’s the glitter path reflection of Aldebaran, which is just below the tail end of the white arrow in alter-ego’s annotated clip. Not far to the right of that, there’s a faint glitter path of Theta 1 & 2 Tau.

[neufer]

1) The water in the picture appears to be a moving stream, not a lake. And that water looks to me to be no more than a few hundred feet wide at most, while Thingvallavatn Lake covers an area of 32 square miles. I have been at that lake, and even from a the cliffs near its northern shore you cannot see the southern shore.

It appears to be the extreme northern section of Thingvallavatn Lake
from a point just off the highway due south of Drekkingarhylur.

64°15'39.9"N 21°07'17.4"W

[alter-ego]

Might that red streak reflected on the lake be a meteor from behind the clouds?

It is possible. The streak coincidentally is short enough and apparently in the right position to be hidden by the cloud that's partially covering Taurus, coincidentally pointing near the Perseid radiant, and is coincidental with the nominal shower duration. The image is dated Aug 24.

I’d be inclined to think that it’s the glitter path reflection of Aldebaran, which is just below the tail end of the white arrow in alter-ego’s annotated clip. Not far to the right of that, there’s a faint glitter path of Theta 1 & 2 Tau.

Yeah, maybe.
I thought the same thing at first, but I didn't think intensity of the streak is not consistent with Aldebaran's brightness and brightness of the nearby star reflections which are questionable as being streaks. However, Aldebaran is 7x to 8x brighter than Tau 2, so maybe all is consistent with smearing by water ripples.

[ems57fcva]

1) The water in the picture appears to be a moving stream, not a lake. And that water looks to me to be no more than a few hundred feet wide at most, while Thingvallavatn Lake covers an area of 32 square miles. I have been at that lake, and even from a the cliffs near its northern shore you cannot see the southern shore.

It appears to be the extreme northern section of Thingvallavatn Lake
from a point just off the highway due south of Drekkingarhylur.

64°15'39.9"N 21°07'17.4"W

I am able to confirm that location as the site for the picture. Even so, there is an obvious flow of water in that picture if you know what to look for. I assume that the stream that flows into that arm of the lake was running high when that picture was taken.

[neufer]

It is possible. The streak coincidentally is short enough and apparently in the right position to be hidden by the cloud that's partially covering Taurus, coincidentally pointing near the Perseid radiant, and is coincidental with the nominal shower duration. The image is dated Aug 24.

I’d be inclined to think that it’s the glitter path reflection of Aldebaran, which is just below the tail end of the white arrow in alter-ego’s annotated clip. Not far to the right of that, there’s a faint glitter path of Theta 1 & 2 Tau.

Yeah, maybe. I thought the same thing at first, but I didn't think intensity of the streak is not consistent with Aldebaran's brightness and brightness of the nearby star reflections which are questionable as being streaks. However, Aldebaran is 7x to 8x brighter than Tau 2, so maybe all is consistent with smearing by water ripples.

The nearness of the pond would imply that
the reflected image is virtually identical to the direct image
(i.e., no revealed sky features that are not directly observable).

Hence, it would seem to be Aldebaran.

[dlw]

Yes -- stretched by the rippling water...

[attachment=0]Aldebaran.jpg[/attachment]

[neufer]

---

Yes -- stretched by the rippling water...

And possibly also focused by the rippling water waves parallel to the streak
which you have pointing to the Pleiades on the right
although caused by Aldebaran on the left.

[dlw]

I always learn something new here!

Thanks!

[khh]

A Rapture hook!

[alter-ego]

...

The nearness of the pond would imply that
the reflected image is virtually identical to the direct image
(i.e., no revealed sky features that are not directly observable).

Hence, it would seem to be Aldebaran.

I agree. At least my original assertion of several coincidences is true. That's all they are