Aurora Over Yellowknife (2009 Sept 22)

[Benbrilling]

The reflection of the moon in the water looks out of whack. Shouldn't the moon be centered over the reflection?

[neufer]

The reflection of the moon in the water looks out of whack. Shouldn't the moon be centered over the reflection?

The moon should also be brighter than its reflection.

But this is a "digitally fused panorama."

[orin stepanek]

http://apod.nasa.gov/apod/ap090922.html

Aw; I like it anyway. An aurora always looks kind of mysterious to me. 8)

Orin

[geckzilla]

Sometimes you have to do perspective adjustments to transition the photos together smoothly. That particular area of the picture could have some curved perspective. If you know how a fisheye lens curves things, what I'm thinking is a similar effect. Or it could have been on the far side of a wide angle shot. It does look odd though because the rest of the lights are nicely vertical.

[neufer]

<<Aurora is now known to be caused by electrons of typical energy of 1-15 keV. The light is produced when they collide with atoms of the upper atmosphere, typically at altitudes of 80-150 km. It tends to be dominated by emissions of atomic oxygen--the greenish line at 5577 A and (especially with electrons of lower energy and higher altitude) the dark-red line at 6300 A. Both these represent "forbidden" transitions of atomic oxygen from energy levels which (in absence of collisions) persist for a long time, accounting for the slow brightening and fading of auroral rays. Many other lines can also be observed, especially those of molecular nitrogen, and these vary much faster, revealing the true dynamic nature of the aurora.
Aurora can also be observed in the ultra-violet (UV) light, a very good way of observing it from space (but not from ground--the atmosphere absorbs UV). The "Polar" spacecraft even observed it in X-rays.>>

[Lasse H]

Sometimes you have to do perspective adjustments to transition the photos together smoothly. That particular area of the picture could have some curved perspective. If you know how a fisheye lens curves things, what I'm thinking is a similar effect. Or it could have been on the far side of a wide angle shot. It does look odd though because the rest of the lights are nicely vertical.

The moon reflection is leaning, but so is the house or boat or whatever is on the far left, so it fits. Same slant towards the right. So maybe en effect from the lens as suggested by geckzilla.

[neufer]

Sometimes you have to do perspective adjustments to transition the photos together smoothly. That particular area of the picture could have some curved perspective. If you know how a fisheye lens curves things, what I'm thinking is a similar effect. Or it could have been on the far side of a wide angle shot. It does look odd though because the rest of the lights are nicely vertical.

The moon reflection is leaning, but so is the house or boat or whatever is on the far left, so it fits. Same slant towards the right. So maybe en effect from the lens as suggested by geckzilla.

The "house or boat or whatever is on the far left" has been pulled up onto a slanting beach.

The boat on the far right is floating on level and it's mast is straight up & down.

<<Yellowknife is the capital of the Northwest Territories (NWT), Canada. It is located on the north shore of Great Slave Lake, approximately 400 km (250 mi) south of the Arctic Circle, on the west side of Yellowknife Bay near the outlet of the Yellowknife River. Yellowknife and its surrounding water bodies were named after the local Yellowknives Dene First Nation, who made tools from regional copper deposits.

• -------------------------------------
  Yellowknife, NWT : 62.44° N, 114.4° W
  North Magnetic Pole ~ 82.7°N, 114.4° W
  -------------------------------------

Yellowknife was first settled in 1935, after gold had been found in the area; Yellowknife soon became the centre of economic activity in the NWT, and became the capital of the Northwest Territories in 1967. As gold production began to wane, Yellowknife shifted from being a mining town to being a centre of government services in the 1980s. However, with the discovery of diamonds north of Yellowknife in 1991, this shift has begun to reverse.>>

[geckzilla]

Are the trees all growing at a slant too, Art?

...But yeah, there's some definite shenanigans going on in the collage. Too hard to tell where the photo seams are though so it's hard to make it make sense. It was probably done on purpose to make sure you guys were paying attention!

[neufer]

Are the trees all growing at a slant too, Art?

Trees often grow at a slant next to an open light source.
More to the point is the vertical tower at the edge of the water.

http://apod.nasa.gov/apod/image/0909/au ... ka_big.jpg

...But yeah, there's some definite shenanigans going on in the collage. Too hard to tell where the photo seams are though so it's hard to make it make sense. It was probably done on purpose to make sure you guys were paying attention!

The moon's 'over bright' reflection appears to be a time exposure.
http://antwrp.gsfc.nasa.gov/apod/ap081120.html

[geckzilla]

I dunno, Art, I think tree trunks are more influenced by gravity than they are the sun. I'd be interested in seeing a forest full of trees which all slant at the same angle because I've never seen it before.

[neufer]

I dunno, Art, I think tree trunks are more influenced by gravity than they are the sun. I'd be interested in seeing a forest full of trees which all slant at the same angle because I've never seen it before.

http://antwrp.gsfc.nasa.gov/apod/ap071114.html

[bystander]

I dunno, Art, I think tree trunks are more influenced by gravity than they are the sun. I'd be interested in seeing a forest full of trees which all slant at the same angle because I've never seen it before.

http://antwrp.gsfc.nasa.gov/apod/ap071114.html

Not a good example, the trees are at two angles, horizontal and vertical. I'm quite certain the horizontal ones were influenced by something more than sunlight and gravity.

[geckzilla]

Haha, I actually thought of Tunguska when I was writing that. You just had to go there.

[NoelC]

The moon comes up crooked that far north.

You thought about that for a few seconds, didn't you.

-Noel