Airglow in Upper Atmosphere

[keehah]

http://astrobob.areavoices.com/astrobob/images/Airglow_and_aurora_NASA.jpg
http://astrobob.areavoices.com/2009/02/25/is-there-true-darkness/

Stars contribute about half of the light at night. The rest comes from a phenomenon called airglow. Yes, the air actually glows all night long. During the day, energetic ultraviolet light from the sun breaks apart molecules of oxygen and nitrogen, and jiggles around the electrons in sodium atoms in our upper atmosphere. At night the excited molecules "calm down" and recombine, emitting red and green light in the process.

Combine airglow and starlight and throw in some snowcover, and you’ve got enough light, even in Earth’s darkest places, to recognize a face or find your way along a road. Cosmic rays also contribute a small fraction of light to the sky. These are subatomic particles careening around the galaxy like kamikazes, ready to zap the atmosphere of any planet that gets in their way. When they strike, they excite atoms and molecules just like the sun’s rays. As the electrons and atoms fall back into place, they release particles of light called photons that contribute to the nighttime illumination.

Although airglow is colorful, it’s far to faint to stimulate our eye’s color receptors, so it looks like faint white streaks and glows. As with so many dim things in the sky, only long exposure photography makes the colors pop.

Airglow is present everywhere on Earth, but can only be seen from very dark places, where it can’t be confused with man-made sources. If you live where darkness rules, allow your eyes a good 20 minutes to "dark adapt", and then scan about one to two outstretched fists above and all around the horizon. Does the sky look a little paler there? If so, it’s likely the glow of busy molecules reuniting 60-80 miles over your head.

Several times on otherwise cloudless nights, I’ve seen airglow overhead. At first I thought the very faint stripes and streaks I saw were clouds, but once I learned about airglow, I realized what I was really seeing. The aurora also involves excited atoms and molecules emitting light, but there’s so much more energy involved, a good display can be seen right from town.

TIME: Artificial Air Glow (http://www.time.com/time/magazine/article/0,9171,891618,00.html#ixzz1TFc4VFak)
Monday, Oct. 24, 1955

An Aerobee rocket soared up last week from Holloman Air Force Base, N. Mex. carrying an odd pay load. Inside its nose were two heavy steel cylinders containing thermite* and 2 lbs. each of metallic sodium. The rocket took off 20 minutes after sunset. When it reached 40 miles and had disappeared from sight, automatic instruments ignited the thermite in the cylinders. The sodium vaporized, jetting out of a hole in the rocket's nose, and a brilliant orange-colored trail appeared against the blue sky. This was the sodium; it picked up the light of the sun, still shining above the shadow of the earth, and reradiated it as brilliant "sodium light."

Orange "G." As the rocket rose to almost 70 miles, the high-altitude winds distorted the sodium-vapor trail into a gigantic "G" 20 miles across. It remained visible for 15 minutes, until the shadow of the earth reached it, and was seen in Amarillo, Texas, 300 miles away.

The sodium rocket was not merely a beautiful and expensive firework; it had a serious scientific purpose: to help the Air Force's long-range study of the upper atmosphere. Part of the "air glow" (the faint glow of the night sky) comes from sodium atoms that absorb solar energy during the day. At night they give off this energy as yellow sodium light. Scientists do not know how high the "sodium layer" is. Nor do they know how the sodium got into the top of the atmosphere. Some think it came from outer space; others suspect that it originated as fine particles of sea salt that were carried upward.

By putting a known amount of sodium vapor into the atmosphere at a known altitude, the sodium rocket will enable scientists to learn more about the natural sodium that is already there. They can compare the air glow coming from the two lots of sodium, and since the amount of one is known, the amount of the other may be calculated.

[keehah]

So how come all the older pictures of space from orbit don't show airglow like the Shuttle Image below? Is it now more common? Or is this one of the possible space physics occulted phenomena now allowed promotion?

CBS News: Photo of a lifetime: Shuttle's fiery trip home (http://www.cbsnews.com/stories/2011/07/21/scitech/main20081517.shtml)

http://i.i.com.com/cnwk.1d/i/tim/2011/07/21/exp28_620x350.jpg
July 21, 2011 3:38 PM
"This unprecedented view of the space shuttle Atlantis, appearing like a bean sprout against clouds and city lights, on its way home, was photographed by the Expedition 28 crew of the International Space Station," NASA officials explained in a photo description. "Airglow over Earth can be seen in the background."

http://www.atoptics.co.uk/highsky/airglow2.htm

Airglow is not always uniform. It can have bands and patches which shift and vary over minutes. Gravity waves propagating from the lower atmosphere modulate the atmospheric density, temperature and composition at airglow altitudes and thus the airglow intensity.

The airglow is brightest on Earth's day side where the original excitation occurs. The night airglow is (fortunately!) only one thousandth as bright and varies through the night. On a much longer timescale the airglow varies with the 11 year cycle of solar activity.
http://philhart.com/content/airglow-and-other-thoughts-dark-sky-sites

Airglow and Gravity Waves
To make things more complicated, airglow is not constant. Disturbances in the atmosphere (confusingly called 'gravity waves') create structure and considerable variation in the airglow.

engineering.illinois.edu Tsunami airglow signature could lead to early detection system (http://engineering.illinois.edu/news/2011/07/13/tsunami-airglow-signature-could-lead-early-detection-system)

July 14, 2011
Researchers at the University of Illinois have become the first to record an airglow signature in the upper atmosphere produced by a tsunami using a camera system based in Maui, Hawaii.
http://engineering.illinois.edu/sites/engineering.illinois.edu/files/resize/research/Makela.airglow%20waves-350x368.jpg


Airglow waves captured by the Illinois imaging system over Hawaii. The red line represents the location of the ocean-level tsunami at the time of the image.
The signature, caused by the March 11 earthquake that devastated Japan, was observed in an airglow layer 250 kilometers above the earth’s surface. It preceded the tsunami by one hour, suggesting that the technology could be used as an early-warning system in the future. The findings were recently published in the peer-reviewed Geophysical Research Letters.

The observation confirms a theory developed in the 1970s that the signature of tsunamis could be observed in the upper atmosphere, specifically the ionosphere. But until now, it had only been demonstrated using radio signals broadcast by satellites.
http://www.sciencenews.org/view/access/id/332172/name/airglow.jpg

http://www.sciencenews.org/view/download/id/332172/name/_
The red and green glowing lights in this picture are “airglow” in the Earth’s ionosphere. (This photo was taken from a space shuttle, visible at left.) The March tsunami that wreaked havoc on Japan produced similar atmospheric, glowing ripples.

Credit: NASA Johnson Space Center

[Horn]

So how come all the older pictures of space from orbit don't show airglow like the Shuttle Image below? Is it now more common? Or is this one of the possible space physics occulted phenomena now allowed promotion?

I've been searching for a photo I saw maybe 8 years ago of a picture of earth from an exploratory satellite that had been launched.

Basically the Earth is an amoeba held within its own mass of atmosphere. A dusty glow extends maybe a full 1/4 of Earth's diameter and there is no clean edge to the atmosphere.

Wonder where that picture went?

[ximmy]

Why do some animals eyes reflect in the dark??

[keehah]

Why do some animals eyes reflect in the dark??
Good eye Ximmy! Mars is not always red. ^-^

http://www.astrosurf.com/cidadao/mars_1999.jpg

http://upload.wikimedia.org/wikipedia/commons/thumb/3/3c/Astrid_com_orelhonas-crop.jpg/220px-Astrid_com_orelhonas-crop.jpghttp://upload.wikimedia.org/wikipedia/commons/thumb/9/96/Calf-Eye-Posterior-With-Retina-Detached-2005-Oct-13.jpg/150px-Calf-Eye-Posterior-With-Retina-Detached-2005-Oct-13.jpg
http://en.wikipedia.org/wiki/Tapetum_lucidum

[Horn]

Just before cell division there is increased strengthening of the exoskeleton.

http://mdk12.org/assessments/high_school/look_like/2009/biology/images/5_q.gif

[keehah]

Ah yes it always boils down to a strengthening of the exoskeleton.

Still it begs the age old question: What came first? The electrical 'gravity waves' (airglow) or the wave?


The March tsunami that wreaked havoc on Japan produced similar atmospheric, glowing ripples.

[Horn]

Things are changing, that's for certain.

The charts on the internet for albedo increase are skewed as far as I can tell.

The egg is of the chicken, and both are only temporal in nature.

[Horn]

http://www.msnbc.msn.com/id/38270609/ns/technology_and_science-space/t/earth-atmosphere-collapse-puzzles-scientists/

updated 7/15/2010 8:09:05 PM ET

An upper layer of Earth's atmosphere recently collapsed in an unexpectedly large contraction, the sheer size of which has scientists scratching their heads, NASA announced Thursday.

The layer of gas called the thermosphere is now rebounding again. This type of collapse (http://www.space.com/scienceastronomy/091217-agu-earth-atmosphere-cooling.html)is not rare, but its magnitude shocked scientists.
"This is the biggest contraction of the thermosphere in at least 43 years," said John Emmert of the Naval Research Lab, lead author of a paper announcing the finding in the June 19 issue of the journal Geophysical Research Letters. "It's a Space Age record."
The collapse occurred during a period of relative solar inactivity called a solar minimum from 2008 to 2009. These minimums are known to cool and contract the thermosphere, however, the recent collapse was two to three times greater than low solar activity (http://www.livescience.com/common/media/video/player.php?videoRef=SP_091112_Sun4%27)could explain.

"Something is going on that we do not understand," Emmert said. ((<--Biscuit, crux of, egg))

The thermosphere lies high above the Earth's surface, close to where our planet meets the edge of space. It ranges in altitude from 55 miles (90 km) to 370 miles (600 km) above the ground. At this height, satellites and meteors fly and auroras shine.
The thermosphere interacts strongly with the sun, so is very affected by periods of high or low solar activity. This layer intercepts extreme ultraviolet light (EUV) from the sun before it can reach the ground.

When solar activity is high, solar EUV warms the thermosphere, causing it to puff up like a marshmallow held over a camp fire. When solar activity is low, the opposite occurs.
Recently, solar activity has been at an extreme low (http://www.space.com/scienceastronomy/090917-sunspot-solar-cycle.html). In 2008 and 2009, sunspots were scarce, solar flares almost non-existent, and solar EUV radiation was at a low ebb.
Still, the thermospheric collapse of 2008-2009 was not only bigger than any previous collapse, it was also bigger than the sun's activity alone could explain.
To calculate the collapse, Emmert analyzed the decay rates of more than 5,000 satellites orbiting above Earth (http://www.space.com/missionlaunches/080225-top10-debris.html)between 1967 and 2010. This provided a space-time sampling of thermospheric density, temperature, and pressure covering almost the entire Space Age.
Emmert suggests carbon dioxide (CO2) in the thermosphere might play a role in explaining the atmospheric collapse.
This gas acts as a coolant, shedding heat via infrared radiation. It is widely-known that CO2 levels have been increasing in Earth's atmosphere. Extra CO2 in the thermosphere could have magnified the cooling action of solar minimum.
"But the numbers don't quite add up," Emmert said. "Even when we take CO2 into account using our best understanding of how it operates as a coolant, we cannot fully explain the thermosphere's collapse."
The researchers hope further monitoring of the upper atmosphere will help them get to the bottom of the situation.

[keehah]

http://i.dailymail.co.uk/i/pix/2011/09/07/article-2034615-0DC0EA6F00000578-110_964x540.jpg
http://www.dailymail.co.uk/sciencetech/article-2034615/The-picture-Saturn-runs-rings-others.html#ixzz1XJQ1phiO

Here’s his explanation of why the image is so unusual: ‘First, the night side of Saturn is seen to be partly lit by light reflected from its own majestic ring system.

‘Next, the rings themselves appear dark when silhouetted against Saturn, but quite bright when viewed away from Saturn, slightly scattering sunlight, in this exaggerated colour image.

‘Saturn's rings light up so much that new rings were discovered, although they are hard to see in the image. Seen in spectacular detail, however, is Saturn's E ring, the ring created by ... the moon Enceladus and the outermost ring visible above.’

He also points out that, if you look very carefully, planet Earth can be seen to the left, just above the bright main rings.

The Cassini-Huygens spacecraft, one of the largest ever built, was launched in 1997 and has taken thousand of breath-taking photographs, as well as providing some remarkable scientific data.

In November 2006, for instance, it spied a storm on Saturn that makes Earth’s hurricanes look like gentle summer breezes.
Raging at the planet’s south pole was a storm measuring 5,000 miles across and 43 miles high, with winds peaking at 350mph. Cassini also discovered seven new moons in orbit around Saturn, bringing the total number to 62.

[StreetsOfGold]

Discussions like this without involving the God who made it.... is useless, meaningless and void of true understanding.

Psalms 95:5 The sea is his, and he made it: and his hands formed the dry land.
Hebrews 11:3 Through faith we understand that the worlds were framed by the word of God, so that things which are seen were not made of things which do appear.

[keehah]

http://www.theoi.com/Protogenos/Khronos.html
Orphica, Epicuras Fragment (from Epiphanius) :
"And he [Epicurus] says that the world began in the likeness of an egg, and the Wind [Khronos (Time) and Ananke (Inevitability) entwined?] encircling the egg serpent-fashion like a wreath or a belt then began to constrict nature. As it tried to squeeze all the matter with greater force, it divided the world into the two hemispheres, and after that the atoms sorted themselves out, the lighter and finer ones in the universe floating above and becoming the Bright Air [Aither or Ouranos] and the most rarefied Wind [Khaos the Air?], while the heaviest and dirtiest have veered down, become the Earth (Ge), both the dry land and the fluid waters [Hydros or Pontos?]. And the atoms move by themselves and through themselves within the revolution of the Sky and the Stars, everything still being driven round by the serpenti form wind [Khronos and Ananke?]."

http://www.theoi.com/Protogenos/Aither.html
AITHER (or Aether) was the Protogenos (first-born elemental god) of the bright, glowing upper air of heaven - the substance of light. Above him lay the solid dome of the sky-god, Ouranos, and below, the transparent mists of earth-bound air. In the evening his mother Nyx drew her veil of darkness between the aither and the aer to bring night to man. In the morn his sister-wife Hemera dispersed these mists, revealing the shining blue aither of day. Night and day were regarded as quite independent of the sun in the ancient cosmogonies.

Aither was one of the three "airs". The middle air was Aer or Khaos, a colourless mist which enveloped the mortal world. The lower air was Erebos, the mists of darkness, which enveloped the dark places beneath the earth and the realm of the dead. The third was the upper air of aither, the mist of light, home of the gods of heaven. It enveloped the mountain peaks, clouds, stars, sun and moon. The stars themselves were said to be formed from the concentrated fires of aither.

His female counterpart was Aithre, Titanis of the Clear Blue Sky, mother of the Sun and Moon.