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NASA Hiding True Colours

GiantRobot said:
Check out today's Astonomy Picture of the Day, from NASA's website, courtesy of the JPL...

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

http://antwrp.gsfc.nasa.gov/apod/image/0401/marsperspective_spirit_med.jpg

It's clearly showing those blue rocks that appear in the "naturally coloured" pictures. Seems like some of the NASA/JPL scientists are getting annoyed with the constant changing of the colours, and are trying to get out as many natural ones as possible. :cool:
Except, they look like 3d modelled reconstructions, mentioned here:

http://fire.prohosting.com/cleoger/marscolors/

This picture above has been taken from http://www.jpl.nasa.gov/mer2004/rover-images/jan-12-2004/captions/image-5.html


This colour calibration seems to be confirmed by scientists of Ames Research Center. They created a 3D-model of this anomaly:

....

It's of high scientific relevance that the colours are displayed correct. As you can see, there are displayed blue rocks, which might indicate they might be iron ore rocks.


Sorry! But, nice try! Keep looking! :)
 
Mars: The Not so Red Planet?

One thing has never sat well with me concerning all of the photos that are taken from Mars surface landers. I firmly believe that all the photos that we are shown are in fact not true color image. I believe for one reason or another they purposely pump red into the photos before they are released. Here is my examples that I have been working on.

First is the image we are regularly force fed as being a “true color” image of the mars surface.

http://www.imagestation.com/album/?id=4287989451&idx=2

Here is a photo that I color corrected myself. I went in and took out about 30% Magenta and 50% Yellow and about 5% Cyan....I did not add any blue or cyan to the photo the blueish color was pretty much there all along just pumped full of yellow and magenta.

http://www.imagestation.com/album/?id=4287989451&idx=1

I am not one to put much credit into conspiracy theories...I believe we went to the moon and that we are actually on the Martian surface. However, I just do not buy the color of the images we are being shown of the “Red” planet.

Why would NASA/JPL be inclined to feel the need to do such a thing? One explanation that I can think of is they do not want anyone to know that Mars is not as hostile an environment as we are led to believe.

Comments? Critiques? Ideas?
 
The problem with your picture is that the colour of the sky indicates a nirtogen heavy atmosphere. Which Mars does not have.

Have you ever looked at it through a telescope? It does indeed like quite red. The colour is down to the proliferation of oxidised iron ore and iron rich rock.

In fact, one of the main ideas behind the terraforming of Mars was based on the release of vast amounts of oxygen from the rocks which form the topsoil of the planet through melting the polar cap which is made of ice. I'm not entirely sure about this would work mind, but hey, I'm sure greater minds than mine have come up with this idea. :)
 
The flaw with the terraforming idea is that Mars has no active Plate Tectonics. Ergo no way to recycle its own oxygen and minerals. That is part of the reason Mars is in the state it is in now.

However, how are we to know if there is not actually nitrogen in the atmosphere? This information could be manipulated as easy as the color images we are being show.
 
That "joy stick" (Mars dial)

There is a close up of the colour calibration chart on the "Mars Dial" here:

http://marsrovers.jpl.nasa.gov/gallery/press/spirit/20040108a/PIA05017_br.jpg

The blue has not been altered to red as in the other image appearing on the net.

Auto equalising in photoshop and similar tends to make images of reddish landscapes look more blue. In the example attached the raw image is nearer the colours the eye would see.
 
stu neville said:
Yes, I noticed that just now, too. How odd...

Or not - the site's owner may have realised that he/she's got it wrong.

Personally, I can't see why people are fretting over this stuff. Firstly, cameras tend not to take exactly the same quality image time after time, even of the same composition (unless you spend alot of time setting up the shot, lighting, etc). This is even more true of digital cameras. Combine that with what may be some slightly inept use of Photoshop and the 'mystery' tends not be one after all.
 
comments on "arguments" againsat premise that NASA

To all:

I have pointed out, numerous times before, that the unscrupulous defenders of patent falsity will resort to specious "explanations" to promote their point. They have to. If they are endorsing a lie, they will not have truth to support it, and so must utilize the non-valid, and rely on the unfamiliarity of others with the subject or the material addressed to defraud them.

It is also the case that those who behave reliably, even predictably conniving cannot, in any reasonableness, be characterized as not being inherently duplicitous and unprincipled.

In their "explanation" of the color of the "Mars pictures" - at this point, their veracity has to be as much called into question as those purportedly from the "moon mission"! - JerryB opines: "Personally, I can't see why people are fretting over this stuff. Firstly, cameras tend not to take exactly the same quality image time after time, even of the same composition (unless you spend alot of time setting up the shot, lighting, etc). This is even more true of digital cameras. Combine that with what may be some slightly inept use of Photoshop and the 'mystery' tends not be one after all."
Among other things - indeed, one of the first things to recognize! - is JerryB's admonishment that, essentially, people shouldn't "fret over this stuff". The unscrupulous always try to convince their targets that they shouldn't put their minds to what the unscrupulous is doing. "Pay no attention to the man behind the curtain!" They want their "pigeons" to be unthinking and disinterested, especially in things that are not right. To see anyone effectively counsel you to "sit down and shut up" is to see an insight into an endeavour with unsavory, even unethical, undercurrents.
They then go on to assert that "cameras tend not to take exactly the same quality image time after time." This is, apparently, intended to "explain away" the fact that an early "image from Mars", one showing a blue sky, included a close-up of the lander's sundial, with colored strips. Later images showed pinkish skies, and close-ups of the sundial showed the colored strips to have been altered, most especially, a blue strip converted to red! Indicating that blue tints in the pictures seem to have been changed to red. JerryB seems to want to defraud their targets into thinking that color must be expected to change, from one exposure to the next, so that a deliberate alteration of color should not be inferred. But better than 99% of all the images, from Viking, Sojourner and, now, Spirit have shown pinkish skies! If JerryB's suggestion is valid, there should be a significant proportion of pictures that have blue skies! It should not be the case that the majority have pink skies! For all that JerryB seems intent on suggesting a random artifact of the photographic process produced bluish skies in the pictures, the patent plurality of pink sky pictures utterly outweighs the idea! In fact, the proportion of blue sky to pink sky pictures mirrors that of individuals defiantly refusing to engage in connivery sneaking through real images, in the midst of false ones!
JerryB then goes on to talk about some "slightly inept use of Photoshop" in the "images from Mars". Are we to believe that millions are spent on a mission to the planet with no provision made for either providing consistent imaging, and, then, doctoring with a store-bought image software package? "Budget concerns" does not apply to the idea of providing automatically verifiable images! If the engineers were not there with the lander, how even would they know that their alteration was correct? An answer is, among other things, to use the color bands on the sundial. But it is observed that the color bands have been altered! Why does JerryB not address this issue?
Fortis "explains" that: "The problem with using the colour calibration charts is that you effectively adjust the colour balance until the coloured dots look the same as they would on earth. The illumination source on Mars is going to be a mixture of transmitted direct sunlight, and light scattered by the atmosphere (i.e. skyshine.) What this means is that you effectively have taken the martian landscape and simulated what it would look like under earthlike illumination conditions. (i.e sun in a blue sky.)" Blue is blue, no matter where the picture is taken! More glaring, however, is the fact that the photograph of the sundial was taken from only a few feet away, or less! No degree of "coloration" in the atmosphere should affect a photograph taken only a few dozen inches away!
There is no reason not to see JerryB's and Fortis' representations as anything more than calculated disingenuousness.
And color isn't the only issue at hand. AndroMan points out, correctly, that "apparent sharpness, polychromacity and clarity of the un-adjusted, redshifted images" disappears in the evidently red-tinted ones! Edges almost seem to melt, one into the other. The pink sky images also seem to have definite lack of clarity, from color borders between different regions being, essentially, erased. And no one in their right mind can possibly believe that the areas depicted could possible have so uniform a color scheme! Nowhere where there is any kind of geological process could there possibly be so solid and uniform a coloration! Even lava, extruded as a chemically homogenous mass, will solidify with striations and patches of different coloration! Add that sandstorms are credited with wearing down rock, and moving particles all over the planet, and you have to have a variation of colors! These facts seem to have been carefully left unanswered by JerryB and Fortis!
If you look at the web page, antwrp.gsfc.nasa.gov/apod/ap030827.html, you will see a photograph of Mars, taken from the Hubble telescope, in orbit. Above the major part of the earth's atmosphere, little, if any, effect on the color of the planet should be visible. Given, too, that Mars' atmosphere is no denser than the upper stratosphere, there should not be significant alteration of color, there, either. Yet the color is nowhere near the unbroken, deep maroon of the "Mars pictures"! Accepting their validity seems utterly unwise; counselling someone to accept them without question seems utterly disrespectful to them!
In the end, it does tragically appear as though there is no reason - beyond being ordered to slavishly believe everything that government tells you to believe! - that what are purported to be photographs from Mars are fabricated images from the earth!



Julian Penrod
 
Re: comments on "arguments" againsat premise that

Straining at Gnats and swallowing camels.

julianpenrod said:
.......In the end, it does tragically appear as though there is no reason - beyond being ordered to slavishly believe everything that government tells you to believe! - that what are purported to be photographs from Mars are fabricated images from the earth!..........

Your position on any matter seems to be that all the evidence from 'conventional science' (mentioned in your other posts) or government agencies is fake.

Everything put out by people with whom you agree, no matter how little evidence there is, is true, and the reason that there is no evidence is because conventional science, the government, or anyone who doesn't agree with you is hiding the evidence, is lying, or has some hidden agenda...or all of these.

Please, don't bother with another one of your thousand word diatribes...because you say it long and loud doesn't make it true.
 
Meantime, mission controllers say they're working to determine if the red planet is actually red.

The colors seen in the pictures the rover sent back to Earth are approximations. The pictures were color-balanced to approximate what a person might see standing on the martian surface.

NASA cautions it could be weeks before scientists perform the calculations to show true color.

http://www.click2houston.com/technology/2784291/detail.html
 
Ha! They're backpedaling! How the heck does one get dust storms on a freezing cold, thin atmosphere planet anyway? And (!), how does the dust stay in the atmosphere to make the sky red, if the atmosphere is thin?
 
Mana said:
...How the heck does one get dust storms on a freezing cold, thin atmosphere planet anyway? And (!), how does the dust stay in the atmosphere to make the sky red, if the atmosphere is thin?

Dry as a bone, very fine dust, and lower gravity so that the dust doesn't settle as rapidly as it would in comparable thin air at Earth gravity? Cold doesn't really matter as long as there are temperature and pressure gradients to generate wind.

I must admit I thought the sky would be a deeper colour, much like that deep blue you get at high altitude because of the thinner air.

I don't think there's a conspiracy, IMHO they're just twiddling with the colour balance at the moment to give something that looks reasonable for the press. It'll probably take a lot more effort to decide what the colours would really look like.

It also occurs to me that on Mars the overall level of light will be lower than on Earth because of the greater distance from the sun. If you were there you probably wouldn't notice, unless you were instantly transported back to Earth, as your eyes would adjust. Whether they should tweak the brightness on the images is possibly another issue.

EDIT*
The prohosting site seems to have gone the same way as a lot of Mars probes. Or it could be the conspiracy...;)
 
I agree with what Timble has said. There's no point chasing after windmills, after all ;)
 
Re: comments on "arguments" againsat premise that

julianpenrod said:
I have pointed out, numerous times before, that the unscrupulous defenders of patent falsity will resort to specious "explanations" to promote their point. They have to. If they are endorsing a lie, they will not have truth to support it, and so must utilize the non-valid, and rely on the unfamiliarity of others with the subject or the material addressed to defraud them.

And as I've pointed out elsewhere, people who don't share your views on any given subject aren't part of some dastardly plan to 'defraud' anyone. We're merely expressing our opinions, which is not (the last time I checked) any sort of Universal Truth.

As for the subject at hand - no-one has proved that the landing nor photos in question are a 'patent falsity'. Unless you 'have the truth to support it' yourself...
 
Re: comments on "arguments" againsat premise that

julianpenrod said:
To all:
Later images showed pinkish skies, and close-ups of the sundial showed the colored strips to have been altered, most especially, a blue strip converted to red! Indicating that blue tints in the pictures seem to have been changed to red.


The only image I have seen with this radical colour change is from a private website where it could easily have been changed using even very primative image editing. All the NASA photos show the colours in the correct places
julianpenrod said:
JerryB seems to want to defraud their targets into thinking that color must be expected to change, from one exposure to the next, so that a deliberate alteration of color should not be inferred. But better than 99% of all the images, from Viking, Sojourner and, now, Spirit have shown pinkish skies! If JerryB's suggestion is valid, there should be a significant proportion of pictures that have blue skies!


There were blue skies in the Viking and Spirit pictures, but only at sunrise and sunset.

julianpenrod said:
More glaring, however, is the fact that the photograph of the sundial was taken from only a few feet away, or less! No degree of "coloration" in the atmosphere should affect a photograph taken only a few dozen inches away!


If I illuminate the room with a red bulb everything in the room will look red no matter how far or near it is from me.

julianpenrod said:
And color isn't the only issue at hand. AndroMan points out, correctly, that "apparent sharpness, polychromacity and clarity of the un-adjusted, redshifted images" disappears in the evidently red-tinted ones! Edges almost seem to melt, one into the other. The pink sky images also seem to have definite lack of clarity, from color borders between different regions being, essentially, erased.


The oposite is true - on earth distant horizons look sharper through a red filter which counteracts the blue haze, on Mars turning the image blue will reduce the effect of pink haze

julianpenrod said:
Add that sandstorms are credited with wearing down rock, and moving particles all over the planet, and you have to have a variation of colors!


I wolud have thought this would make colours more uniform

julianpenrod said:
In the end, it does tragically appear as though there is no reason - beyond being ordered to slavishly believe everything that government tells you to believe! - that what are purported to be photographs from Mars are fabricated images from the earth!

Its not my government and there are a lot of things I think they are lying about. Mars is not one of them! NASA is admirably open with its information.
 
Well, I just saw a news report on CNN, about the problems with the 'Spirit' rover.

The 'Spirit' photos from NASA they were using, were still the deep maroon, color distorted ones, where the blues of wiring and labels (like the one on the sundial) come out as a bright pink/purple color.

There is no doubt in my mind that most of the shots used to publicise the Mars mission are chromatically distorted towards the red end of the spectrum.

There's times it looks more like the surface atmosphere of Venus than Mars. And that surely can't be right.

Okay, so there's plenty of dust in the thin Martian atmosphere, but even so I think it's possible that the colors are being exaggerated.
 
Re: comments on "arguments" againsat premise that

julianpenrod said:
There is no reason not to see JerryB's and Fortis' representations as anything more than calculated disingenuousness.
Hurrah, I'm now being disingenuous. ;)

Main Entry: dis·in·gen·u·ous
Pronunciation: "di-s&n-'jen-y&-w&s
Function: adjective
Date: 1655
: lacking in candor; also : giving a false appearance of simple frankness : CALCULATING


Julian, have you ever wondered what the colour balance bit in Photoshop is all about? ;)

(Photoshop is the software that one can use to add persistent contrails to satellite imagery. ;) )
 
It is a shame that Spirit has gone quiet;

but if anyone is still interested, an explanation for the colour shifts can be found here
http://www.atsnn.com/story/30048.html

provided by 'Professor James Bell, who is the Pancam Payload Element Lead for the mission'.


It appears that the red portion of the image we see is actually the infrared portion of the spectrum, which shows the blue pigment as bright , while a true red image would show it dark.

As nobody sees infrared images naturally, these pictures do not really represent what a person standing there would see, and no simple colour adjustment in photoshop or any such program gould make them appear so.
 
Eburacum45 said:
It is a shame that Spirit has gone quiet;

but if anyone is still interested, an explanation for the colour shifts can be found here
http://www.atsnn.com/story/30048.html

Thanks for posting this. I have been experimenting and had come to the conclusion that the colour filters on Spirit were not just RGB.

If you download the raw images from the NASA website you find you get natural colour on the close up of the sundial when you combine three of them as a RGB image, but you get the pink colour when you combine three wide angle shots. I was on the point of joining the conspiracy theorists, then I noticed the "Red filter" in some images was number 2, and number 4 in the "natural" looking images. According to the website 2 is infrared. It all makes much more sense when you know that. If you have ever taken photos on Earth with infra red film the colours you get ar fairly strange!
 
Forgive me for being crude, or whatever-but this whole mars business is a thorn in my side.
Why bother going if not to find something?
And, I think the sky on mars is BLUE! Why, because the SPIRIT rover dragged a sh*t load of mud across the terrain and the geniuses at NASA who have been pumping false info since the lunar landings, are scratching their heads like the lab monkeys that they are.
Don't get me wrong, I have respect for them. I even wanted to work for NASA (a millenia ago) but, the people at NASA who record these photos and the info from the Rover have bosses, and their bosses run the show and their bosses say whether the rest of the world can see certain images and how they will see them.
If SPIRIT tracked mud, that means their is water, which means there's a blue sky, which means that MARS is indeed EARTH's twin, which means the odd structures in CYDONIA could be artificial, which can only mean one darn thing- THERE IS/WAS LIFE ON MARS.

that said, I am going to take my meds now.

WW
 
<Scratches head>....NASA, werent they those clowns who realeased that stupid `face on mars` picture?....

Just because Mars may be more Earthlike than thought doesnt mean that there are artificial structures....I think archaelogy on Mars would be a doddle, same as in deserts on Earth, little erosion or decay and all the structures stick out like sore camels!
 
WonderWoman said:
Why, because the SPIRIT rover dragged a sh*t load of mud across the terrain If SPIRIT tracked mud, that means their is water, which means there's a blue sky, which means that MARS is indeed EARTH's twin, which means the odd structures in CYDONIA could be artificial, which can only mean one darn thing- THERE IS/WAS LIFE ON MARS.

Mud:confused:

The close up photos make it look more like very fine talcy soil.
ESA reported detecting water ice at the south pole today, I think if NASA had detected any water they would have made sure they announced it first. They landed in an old lake bed so I think that is what they were after. Quite why you think water would make the sky blue I don't know - it was grey here all day and we have loads of water.:)

I suspect NASA would prefer blue skies, if Mars was more Earth like then they would get more funding.
 
[Physics FAQ] - [Copyright]

Original by Philip Gibbs May 1997.




Why is the sky blue?
A clear cloudless day-time sky is blue because molecules in the air scatter blue light from the sun more than they scatter red light. When we look towards the sun at sunset, we see red and orange colours because the blue light has been scattered out and away from the line of sight.



The white light from the sun is a mixture of all colours of the rainbow. This was demonstrated by Isaac Newton, who used a prism to separate the different colours and so form a spectrum. The colours of light are distinguished by their different wavelengths. The visible part of the spectrum ranges from red light with a wavelength of about 720 nm, to violet with a wavelength of about 380 nm, with orange, yellow, green, blue and indigo between. The three different types of colour receptors in the retina of the human eye respond most strongly to red, green and blue wavelengths, giving us our colour vision.

Tyndall Effect
The first steps towards correctly explaining the colour of the sky were taken by John Tyndall in 1859. He discovered that when light passes through a clear fluid holding small particles in suspension, the shorter blue wavelengths are scattered more strongly than the red. This can be demonstrated by shining a beam of white light through a tank of water with a little milk or soap mixed in. From the side, the beam can be seen by the blue light it scatters; but the light seen directly from the end is reddened after it has passed through the tank. The scattered light can also be shown to be polarised using a filter of polarised light, just as the sky appears a deeper blue through polaroid sun glasses.

This is most correctly called the Tyndall effect, but it is more commonly known to physicists as Rayleigh scattering--after Lord Rayleigh, who studied it in more detail a few years later. He showed that the amount of light scattered is inversely proportional to the fourth power of wavelength for sufficiently small particles. It follows that blue light is scattered more than red light by a factor of (700/400)4 ~= 10.

Dust or Molecules?
Tyndall and Rayleigh thought that the blue colour of the sky must be due to small particles of dust and droplets of water vapour in the atmosphere. Even today, people sometimes incorrectly say that this is the case. Later scientists realised that if this were true, there would be more variation of sky colour with humidity or haze conditions than was actually observed, so they supposed correctly that the molecules of oxygen and nitrogen in the air are sufficient to account for the scattering. The case was finally settled by Einstein in 1911, who calculated the detailed formula for the scattering of light from molecules; and this was found to be in agreement with experiment. He was even able to use the calculation as a further verification of Avogadro's number when compared with observation. The molecules are able to scatter light because the electromagnetic field of the light waves induces electric dipole moments in the molecules.

Why not violet?
If shorter wavelengths are scattered most strongly, then there is a puzzle as to why the sky does not appear violet, the colour with the shortest visible wavelength. The spectrum of light emission from the sun is not constant at all wavelengths, and additionally is absorbed by the high atmosphere, so there is less violet in the light. Our eyes are also less sensitive to violet. That's part of the answer; yet a rainbow shows that there remains a significant amount of visible light coloured indigo and violet beyond the blue. The rest of the answer to this puzzle lies in the way our vision works. We have three types of colour receptors, or cones, in our retina. They are called red, blue and green because they respond most strongly to light at those wavelengths. As they are stimulated in different proportions, our visual system constructs the colours we see.


Response curves for the three types of cone in the human eye

When we look up at the sky, the red cones respond to the small amount of scattered red light, but also less strongly to orange and yellow wavelengths. The green cones respond to yellow and the more strongly-scattered green and green-blue wavelengths. The blue cones are stimulated by colours near blue wavelengths which are very strongly scattered. If there were no indigo and violet in the spectrum, the sky would appear blue with a slight green tinge. However, the most strongly scattered indigo and violet wavelengths stimulate the red cones slightly as well as the blue, which is why these colours appear blue with an added red tinge. The net effect is that the red and green cones are stimulated about equally by the light from the sky, while the blue is stimulated more strongly. This combination accounts for the pale sky blue colour. It may not be a coincidence that our vision is adjusted to see the sky as a pure hue. We have evolved to fit in with our environment; and the ability to separate natural colours most clearly is probably a survival advantage.


A multi-coloured sunset over the Firth of Forth in Scotland.

Sunsets
When the air is clear the sunset will appear yellow, because the light from the sun has passed a long distance through air and some of the blue light has been scattered away. If the air is polluted with small particles, natural or otherwise, the sunset will be more red. Sunsets over the sea may also be orange, due to salt particles in the air, which are effective Tyndall scatterers. The sky around the sun is seen reddened, as well as the light coming directly from the sun. This is because all light is scattered relatively well through small angles--but blue light is then more likely to be scattered twice or more over the greater distances, leaving the yellow, red and orange colours.


A blue haze over the mountains of Les Vosges in France.

Blue Haze and Blue Moon
Clouds and dust haze appear white because they consist of particles larger than the wavelengths of light, which scatter all wavelengths equally (Mie scattering). But sometimes there might be other particles in the air that are much smaller. Some mountainous regions are famous for their blue haze. Aerosols of terpenes from the vegetation react with ozone in the atmosphere to form small particles about 200 nm across, and these particles scatter the blue light. A forest fire or volcanic eruption may occasionally fill the atmosphere with fine particles of 500-800 nm across, being the right size to scatter red light. This gives the opposite to the usual Tyndall effect, and may cause the moon to have a blue tinge since the red light has been scattered out. This is a very rare phenomenon--occurring literally once in a blue moon.

Opalescence
The Tyndall effect is responsible for some other blue coloration's in nature: such as blue eyes, the opalescence of some gem stones, and the colour in the blue jay's wing. The colours can vary according to the size of the scattering particles. When a fluid is near its critical temperature and pressure, tiny density fluctuations are responsible for a blue coloration known as critical opalescence. People have also copied these natural effects by making ornamental glasses impregnated with particles, to give the glass a blue sheen. But not all blue colouring in nature is caused by scattering. Light under the sea is blue because water absorbs longer wavelength of light through distances over about 20 metres. When viewed from the beach, the sea is also blue because it reflects the sky, of course. Some birds and butterflies get their blue colorations by diffraction effects.

Why is the Mars sky red?
Images sent back from the Viking Mars landers in 1977 and from Pathfinder in 1997 showed a red sky seen from the Martian surface. This was due to red iron-rich dusts thrown up in the dust storms occurring from time to time on Mars. The colour of the Mars sky will change according to weather conditions. It should be blue when there have been no recent storms, but it will be darker than the earth's daytime sky because of Mars' thinner atmosphere.
The colour of the Mars sky will change according to weather conditions. It should be blue when there have been no recent storms, but it will be darker than the earth's daytime sky because of Mars' thinner atmosphere.
 
You need nitrogen for blue skies, IIRC. Something to do with scattering, refractive indices and absorbtion...
 
No. It makes no difference what the chemical composition of the atmosphere is. What happens is that as the star's light (why restrict ourselves to this solar system?) enters the upper atmosphere, it is refracted. As it is composed of different wavelengths, the different wavelengths refract at different rates, so that the reddish end is refracted in such a way that it is less visible, and the bluish end is more visible.
 
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