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9/22/2005: Red flash moon
Katkeeper points out that the IotD has featured a green flash on the sun before so why not today's ApoD, which is a red flash on the moon? OK.
You can see more green color at the top and more red at the bottom, too. ApoD explains: While the long sight-line through the atmosphere filters and reddens the moonlight, it also bends different colors of light through slightly different angles, producing noticeable red (bottom) and green (top) lunar rims. Also captured here floating just below the Moon is a thin, red mirage (inset) -- in this case, an atmospherically magnified and distorted image of the red rim.
BigV Thursday Sep 22 08:18 PM
That's cool.
Not that I need another photographic holy grail to seek, after striving to capture a green flash at sunset. I never did catch one myself, but I thoroughly enjoyed the quest. Nice picture. Thanks, UT.
xoxoxoBruce Thursday Sep 22 08:47 PM
I'd heard of the harvest moon and the hunters moon but never heard of a Goatse moon. 
glatt Thursday Sep 22 09:55 PM
Very cool.
busterb Thursday Sep 22 09:58 PM
TW will be along to explain why that's all BS
tw Thursday Sep 22 10:56 PM
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Originally Posted by busterb
TW will be along to explain why that's all BS |
Also part of this experiment is measuring light intensity of the sun. It too varies. Numerous variable. Equipment that must remain calibrated for minor variations of light intensity over generations. Complex study.
BigV Thursday Sep 22 11:08 PM
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Originally Posted by tw
How much light passes through the earth's atmosphere and illuminates the moon has been an ongoing experiment for some decades now. Research has suggested a substancial decrease in light absorbing materials in earths atmosphere. If air is dirtier, then global warming has occurred slower.
Also part of this experiment is measuring light intensity of the sun. It too varies. Numerous variable. Equipment that must remain calibrated for minor variations of light intensity over generations. Complex study. |
Hey, tw. The moon is illuminated by the sun, not by the earth. The clarity of the atmoshphere affects the visibility of the moon from earth of course.
I have read nothing that suggests the conclusion that dirtier air is evidence of slowed global warming.
wolf Friday Sep 23 02:12 AM
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Originally Posted by xoxoxoBruce
I'd heard of the harvest moon and the hunters moon but never heard of a Goatse moon.
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Hobbs Friday Sep 23 02:41 AM
You're all wrong!!!! Everyone knows the moon is made of red cheese.
Jeeze!
Pie Friday Sep 23 08:55 AM
Mmmmm... Gouda!
Trilby Friday Sep 23 09:19 AM
I did not know what Goatse was. Thanks to Google, and xoxoxobruce, now, I do.
I learn something new every damn day.
glatt Friday Sep 23 09:34 AM
I'm sorry you had to find out what Goatse is. You didn't actually see him, did you?
seakdivers Friday Sep 23 02:06 PM
Oh my god. I didn't know what Goatse was either. I just went and looked it up.
I cannot unsee what I saw.
wolf Friday Sep 23 02:14 PM
We've all had that exact same wish.
And somehow, the power of the image is such that every time from here on out that someone so much as mentions it, you'll vomit in your throat a little bit. Every single time.
I feel your pain.
(N.B. the upside is that while the image swims to the fore of your consciousness when you see the name, it does not remain in the front of your head all the time. It doesn't stick there, like the Barney Song or The Chicken Dance Tune. Repression is a protective mechanism for the brain. The human brain is a miraculous machine. This proves it.)
glatt Friday Sep 23 02:35 PM
Such is the power of Goatse. It's actually quite amazing. You say things like, "I'm sorry you saw Goatse." other people say things like "I wish I could go back in time and not see Goatse." The message couldn't be more plain. YOU WILL BE SORRY IF YOU LOOK AT GOATSE.
And yet others will come, read those comments, be curious, and actively seek out Goatse. Goatse is a power that can't be stopped. Almost like a black hole. Once you have heard the mention of Goatse, you have crossed the event horizon, and nothing you can do will keep you from being sucked in.
Undertoad Friday Sep 23 03:05 PM
wikipedia is a good source of info if you don't want to just look at the thing
seakdivers Friday Sep 23 04:07 PM
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Originally Posted by glatt
Goatse is a power that can't be stopped. Almost like a black hole.
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It was more red than black...
LabRat Friday Sep 23 04:26 PM
Well, thank you for the wikipedia referance. I too had never heard of this, and thankfully will refrain from actualy seeing the image after reading the wikipedia background. I must assume that the picture isn't photoshopeed.
O. M. G.
wolf Saturday Sep 24 02:04 AM
You looked, didn't you. Everybody looks. It's like the tickle on the back of your neck that won't go away, but you can't find the spider that you're sure is causing it. You keep at it and at it and at it ...
"Don't look, Marion!!"
Happy Monkey Saturday Sep 24 08:48 AM
I would like to suggest that nobody looks up "tubgirl" either. Worse than goatse.
wolf Saturday Sep 24 11:56 AM
I didn't realize that had a name.
seakdivers Saturday Sep 24 11:56 AM
Too late.
God I hate being a curious person sometimes.
xoxoxoBruce Saturday Sep 24 02:31 PM
My bad.....I figured anybody thats been on the net more than a couple months would have run across Goatse at some point. Didn't realize there were so many innocents abroad. 
But, but, but.....I didn't post a link.
BigV Saturday Sep 24 05:21 PM
In this case, I will believe what I see on the internet and preserve my goatse-tubgirl virginity. Thanks guys.
mitheral Sunday Sep 25 02:42 AM
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Originally Posted by BigV
Must be my turn in the box...
Hey, tw. The moon is illuminated by the sun, not by the earth. The clarity of the atmoshphere affects the visibility of the moon from earth of course. I have read nothing that suggests the conclusion that dirtier air is evidence of slowed global warming. |
tw Tuesday Sep 27 12:40 AM
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Originally Posted by mitheral
I think tw is talking about illumination of the moon when it is in earths penumbra or during an eclipse when some to all of the light hitting the moon has been filtered thru the earth's atmosphere.
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xoxoxoBruce Tuesday Sep 27 01:41 AM
We've discussed it before.....also Earth's gravity bending light slightly.....but it was probably a while ago. May not have been in IOtD either. 
BigV Tuesday Sep 27 01:53 PM
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Originally Posted by tw
Correct. The moon would be completely dark. But sunlight passing through the earth's atmosphere is refracted.
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Originally Posted by tw
Lowest frequency light is bent most which is why the moon glows red.
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Originally Posted by tw
Intensity of that light measures atmosphere clarity. This intensity must be compensated for by adjustments in the moon's orbit (apogee and perigee, etc), variation in sun's intensity, how the light is measured, etc. These experiments have been ongoing for decades. I thought I had posted a description previously in The Cellar. Apparently not.
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The French astronomer A. Danjon proposed a useful five point scale for evaluating the visual appearance and brightness of the Moon during total lunar eclipses. 'L' values for various luminosities are defined as follows: L = 0 Very dark eclipse. Moon almost invisible, especially at mid-totality. L = 1 Dark Eclipse, gray or brownish in coloration. Details distinguishable only with difficulty. L = 2 Deep red or rust-colored eclipse. Very dark central shadow, while outer edge of umbra is relatively bright. L = 3 Brick-red eclipse. Umbral shadow usually has a bright or yellow rim. L = 4 Very bright copper-red or orange eclipse. Umbral shadow has a bluish, very bright rim. |
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| Research has suggested a substancial decrease in light absorbing materials in earths atmosphere. If air is dirtier, then global warming has occurred slower. |
BigV Tuesday Sep 27 01:54 PM
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Originally Posted by tw
Correct. The moon would be completely dark. But sunlight passing through the earth's atmosphere is refracted.
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Originally Posted by tw
Lowest frequency light is bent most which is why the moon glows red.
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Quote:
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Originally Posted by tw
Intensity of that light measures atmosphere clarity. This intensity must be compensated for by adjustments in the moon's orbit (apogee and perigee, etc), variation in sun's intensity, how the light is measured, etc. These experiments have been ongoing for decades. I thought I had posted a description previously in The Cellar. Apparently not.
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The French astronomer A. Danjon proposed a useful five point scale for evaluating the visual appearance and brightness of the Moon during total lunar eclipses. 'L' values for various luminosities are defined as follows: L = 0 Very dark eclipse. Moon almost invisible, especially at mid-totality. L = 1 Dark Eclipse, gray or brownish in coloration. Details distinguishable only with difficulty. L = 2 Deep red or rust-colored eclipse. Very dark central shadow, while outer edge of umbra is relatively bright. L = 3 Brick-red eclipse. Umbral shadow usually has a bright or yellow rim. L = 4 Very bright copper-red or orange eclipse. Umbral shadow has a bluish, very bright rim. |
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| Research has suggested a substancial decrease in light absorbing materials in earths atmosphere. If air is dirtier, then global warming has occurred slower. |
plthijinx Tuesday Sep 27 02:24 PM
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Originally Posted by wolf
You looked, didn't you. Everybody looks. It's like the tickle on the back of your neck that won't go away, but you can't find the spider that you're sure is causing it. You keep at it and at it and at it ...
"Don't look, Marion!!" |
Edit: damn you Wolf!
tw Wednesday Sep 28 05:59 PM
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Originally Posted by BigV
Not so. Although the redder frequencies of the visible portion of the spectrum of light are refracted more than the bluer frequencies, this has nothing to do with the percieved color of the moon in this example. The red of the moon and the blue of the sky are what they are for the same reason: scattering.
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My odometer is only good to a mile. So how do I measure the distance between two points to within a hundreth of a mile? It's called statistics. Take enough data to obtain an accurate reading. Other variables to this experiment are included when taking that data; only some I have listed. But these variables are taken into account when measurements over generations showed a decrease in the amount of light reaching the moon - through earth's atmosphere.
Your assumptions about clouds and crude measuring assume no knowledge of statistics and no use of instruments. These experiements (and others including a measurment of sun's intensity) have been ongoing for decades using calibrated instruments; meaning these 'course measurements' by science have resulted in accurate data.
Meanwhile the course measurements that Big V cited from Danjon Scale of Lunar Eclipse Brightness are how the laymen - without instruments - can ball park the same experiment. That citation also says
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| ... the [earth's] atmosphere refracts some of the Sun's rays into the shadow. Earth's atmosphere contains varying amounts of water (clouds, mist, precipitation) and solid particles (dust, organic debris, volcanic ash). This material filters and attenuates the sunlight before it's refracted into the umbra. For instance, large or frequent volcanic eruptions dumping huge quantities of ash into the atmosphere are often followed by very dark, red eclipses for several years. |
I thank you for confirming what I had posted. The illumination of the moon by light refracted in earth's atmosphere is one method to measure clarity or contamination of earth's atmosphere. Big V confirms how the experiment is performed- and how laymen without instruments can do the same experiment.
BigV Wednesday Sep 28 07:32 PM
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Originally Posted by tw
--I'll get back to this part in a minute, but first--
The accusation of "This sounds like nonsense. Do you care to explain it in more detail?" is posted in direct contradiction to BigV's own citation. Care to explain why you did not read your own citation before posting? --hack-- |
In your first post in this thread, which I quoted twice now, you made this statement:
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| Research has suggested a substancial decrease in light absorbing materials in earths atmosphere. If air is dirtier, then global warming has occurred slower. |
One point at a time...
BigV Wednesday Sep 28 08:38 PM
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Originally Posted by tw
Tell me where all this red 'scattered' light is at midnight? The moon is red because that is the red light refracted through the earth's atmosphere - the only source of light to illuminate the moon. Blue light does not bend sufficiently AND therefore does not illuminate the moon. The amount of red light that illuminates the moon is the amount of red light refracted through the earth's atmosphere.
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Those folks about six hours away in either direction see a rosy sunrise or a rosy sunset, weather conditions permitting. You yourself, and every other non blind or color blind person reading this post has had considerable first hand empirical evidence of this. Pay attention. Because the people near the terminator, the line between light and dark, have to see the sun or moon through so much more atmosphere, so much more blue light is scattered, and the proportion of light that does still get through without having been scattered is much higher in the redder frequencies. Roughly speaking, sunlight minus blue equals red.
Now, let's continue on to midnight. As an observer on the surface of the earth, the sunlight you're able to see at midnight would have to be reflected off of something. This is because the sunlight IS refracted. ALL sunlight. The variation, of how much more or less a given frequency of light is refracted is called dispersion. It only amounts to about 1% across the visible spectrum, and for our purposes, is irrelevant. From here:
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Refraction is slightly different for different colors of light. This variation of the refractive index with the wavelength or frequency of the light is called dispersion. Dispersion is a property of all transparent materials. The color of green flashes is due to the dispersion of air, which makes atmospheric refraction slightly different for different parts of the spectrum. The dispersion of air, like that of water, glass, clear plastics, and most other materials, is small: the refractivity (n - 1) varies by about 1% across the visible spectrum. Because dispersion is so small, it is negligible for many purposes. Only in special situations is the dispersion of air visible to the naked eye. |
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| Refraction in geometric optics is the change in direction of a wave due to a change in velocity. It happens when waves travel from a medium with a given refractive index to a medium with another. At the boundary between the media the wave changes direction; its wavelength increases or decreases but frequency remains constant. For example, a light ray will refract as it enters and leaves glass; understanding of this concept led to the invention of the refracting telescope. |
As the sunlight passes through and is refracted at the space/air boundary, it only CHANGES DIRECTION, NOT FREQUENCY. What goes in red comes out red, what goes in blue comes out blue. But there's the rub. The blue doesn't come out in our lunar eclipse model, it's scattered much much more by the ]dramatically longer slog through our atmosphere than the red is on its way from the sun, through the limb (second definition) of the earth, to the moon and back.
That, tw, is why the moon appears red during an eclipse. The blue frequencies are scattered more than the red frequencies. You only see what gets to your eyes. Or maybe you don't. But not through any fault of mine.
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Originally Posted by tw
My odometer is only good to a mile. So how do I measure the distance between two points to within a hundreth of a mile? It's called statistics. Take enough data to obtain an accurate reading. Other variables to this experiment are included when taking that data; only some I have listed. But these variables are taken into account when measurements over generations showed a decrease in the amount of light reaching the moon - through earth's atmosphere.
Your assumptions about clouds and crude measuring assume no knowledge of statistics and no use of instruments. These experiements (and others including a measurment of sun's intensity) have been ongoing for decades using calibrated instruments; meaning these 'course measurements' by science have resulted in accurate data. Meanwhile the course measurements that Big V cited from Danjon Scale of Lunar Eclipse Brightness are how the laymen - without instruments - can ball park the same experiment. That citation also says BigV's own citation confirms that lunar eclipses measure the clarity of earth's atmosphere. |
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Originally Posted by tw
--covered earlier--
I thank you for confirming what I had posted. The illumination of the moon by light refracted in earth's atmosphere is one method to measure clarity or contamination of earth's atmosphere. Big V confirms how the experiment is performed- and how laymen without instruments can do the same experiment. |
Clodfobble Wednesday Sep 28 09:36 PM
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Originally Posted by BigV
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I think a better wording of tw's statement would be: "Our atmosphere is getting cleaner, according to research. Since dirt particles in the air absorb light, less light is being absorbed, leaving more of it to fall upon the Earth. More light equals more heat, and more heat is sorta similar to the idea of global warming. Therefore, if we had left the dirt in the air, the planet would be warming more slowly than it is now that we're pulling all of this debris out of our atmosphere. This is ironic, because 'clean the air' and 'stop global warming' are two major goals of the environmentalists, and they are seemingly at odds. Ha, ha!"
As to the veracity of his statement, I have no fucking clue. Sounds pretty damn fishy to me. But I'm just the translator here.
tw Thursday Sep 29 02:28 AM
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Originally Posted by Clodfobble
I think a better wording of tw's statement would be: "Our atmosphere is getting cleaner, according to research. Since dirt particles in the air absorb light, less light is being absorbed, leaving more of it to fall upon the Earth. More light equals more heat, and more heat is sorta similar to the idea of global warming. Therefore, if we had left the dirt in the air, the planet would be warming more slowly than it is now that we're pulling all of this debris out of our atmosphere.
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Is more dirty air a good thing? Less light means less crops and less conversion of CO2 into O2. The short term benefits of a dirty atmosphere could have long term negative consequences for agriculture and result in more global warming gases in the long term.
Trilby Thursday Sep 29 07:34 AM
You guys are all pretty smart. I never, never, never think about this stuff (I know--leaving myself wide open for an insult-fest) but, seriously, I never do. Why do you all worry about this? Just enjoy the red moon. Maybe it's a sign of the endtimes or something. 
Happy Monkey Thursday Sep 29 09:28 AM
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Originally Posted by Brianna
You guys are all pretty smart. I never, never, never think about this stuff
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BigV Thursday Sep 29 01:48 PM
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Originally Posted by tw
How much red light illuminates the moon? Depends on clarity of earth's atmosphere. "Our atmosphere is getting dirtier , according to research.
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Originally Posted by tw
Since dirt particles in the air absorb light,
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Dirt in the air is a vanishingly small fraction of the light/heat absorbing components in our atmosphere. The largest contributor to absorbtion of light energy? Water vapor, followed by carbon dioxide and on down the line from there.
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Originally Posted by tw
less light falls upon the Earth. Therefore, if we leave dirt in the air, the planet would be warming quickly as it is currently warming ." IOW global warming problem may be more serious than earlier thought. A problem masked by a dirtier atmosphere. Even with less sunlight, global warming continues.
Is more dirty air a good thing? Less light means less crops and less conversion of CO2 into O2. The short term benefits of a dirty atmosphere could have long term negative consequences for agriculture and result in more global warming gases in the long term. |
You're out of your area of expertise, tw, and it shows. This kind of behavior reminds me of the misguided people who are clamoring for ID to be considered on par with evolution, "cause, it's just a theory, you don't really know. Nyah." Puh-lease.
mitheral Thursday Sep 29 02:05 PM
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Originally Posted by Brianna
You guys are all pretty smart. I never, never, never think about this stuff (I know--leaving myself wide open for an insult-fest) but, seriously, I never do. Why do you all worry about this? Just enjoy the red moon. Maybe it's a sign of the endtimes or something.
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Mitheral: Man the moon sure is bright tonight.
Friend of Mitheral: Did you know that the moon is 1 millionth the brightness of the sun?
M: Say what?
FoM: Ya, I read that a clear sky full moon reflects about 1/1,000,000 of the suns light to the surface of the earth.
M: Not that I don't believe you, what with you being the rocket scientist and all<1>, but let's take Bill Nye's advice to heart<2> and give this a test.
So the next night we head out to a sufficiently dark place away from the light pollution of town with 35mm gear and a stopwatch. A few quick calculations of F-stops and reciprocity failure time fudges and we start taking _long_ exposures of the surrounding scenery.
Five days later (we're not working for the government here so we didn't see any need to pay for 1hr processing) we had a half dozen pictures of what appeared at first glance to be fairly normal looking landscapes.
Until you noticed that the grass was all fuzzy soft looking like a new piece of fleece but fence posts and buildings were razor sharp. There wasn't even much of a colour cast as the moon is a pretty near perfect grey card. The ever so slightly off colours were probably a result of the 4+ minute exposure times. Kind of a '70s techincolour effect.
So yes the light reflected by the moon to earth is about 1 millionth the brightness of the sun.
<1> Sort of, though more a rocket scientist in training, he was an aerospace engineering student.
<2> One test is worth a thousand expert opinions.
mitheral Thursday Sep 29 02:22 PM
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Originally Posted by BigV
whatevah.
You're out of your area of expertise, tw, and it shows. This kind of behavior reminds me of the misguided people who are clamoring for ID to be considered on par with evolution, "cause, it's just a theory, you don't really know. Nyah." Puh-lease. |
Global Dimming which is the observed fact that the brightness of the sun at ground level declined about 5% between the 1950 and 1990. This dimming it's postulated was caused by particulate pollution which has been reduced due to measures like the Clean Air Act in the USA. Of concern is this dimming may have kept the earth cooler that it would otherwise have been during those decades meaning models predicting the effects of green house gasses on global warming may be underestimating their effect. As we continue to reduce particulate emmisions the sun should continue to brighten.
See also the BBC
On the upside this means that solar panels should get more effective.
This isn't intelligent design, just some people publishing an observed effect and others trying to use this knowledge to explain problems in global warming models.
xoxoxoBruce Thursday Sep 29 06:10 PM
When America used to make things and the coal fired smokestacks were belching great plumes of soot, the weather was definitely cooler on the ground. The soot may have been absorbing the heat from the sun and dissipating it around the world for a net increase in total heat, but locally it was cooler.
Billy Budapest Saturday Oct 8 08:09 PM
red moon
Maybe that red phenomenon is the spaceship that the Scientologists say is waiting on the other side of the moon to take us all away to Paradise?
lumberjim Sunday Oct 9 01:00 AM
ok, who let the Canadian in?!
tw Saturday Nov 12 10:15 PM
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Originally Posted by mitheral
I believe tw is talking about Global Dimming which is the observed fact that the brightness of the sun at ground level declined about 5% between the 1950 and 1990. This dimming it's postulated was caused by particulate pollution which has been reduced due to measures like the Clean Air Act in the USA.
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Water builds the heat in Europe The scientists say that rising temperatures caused by greenhouse gases are increasing humidity, which in turn amplifies the temperature rise. This is potentially a positive feedback mechanism which could increase the impact of greenhouse gases such as CO2. ... "We observed that between 1995 and 2002, the amount of longwave radiation coming downwards to the Earth in Europe increased significantly, whereas solar radiation did not," said study leader Rolf Philipona, from the World Radiation Center in Davos, Switzerland. Longwave radiation comes from molecules of gases such as carbon dioxide, methane, and water vapour which have absorbed solar radiation after it has hit the Earth's surface and been reflected back up through the atmosphere. "We wondered if this effect was simply because of a temperature increase at the surface - you would just get more radiation going up, and so more coming back down," Dr Philipona told the BBC News website. |
xoxoxoBruce Saturday Nov 12 10:24 PM
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| you would just get more radiation going up, and so more coming back down," Dr Philipona told the BBC News website. |
Anyway, everyone knows it's not the heat....it's the humidity.
Sundae Monday Nov 14 12:50 PM
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Originally Posted by wolf
You looked, didn't you. Everybody looks. It's like the tickle on the back of your neck that won't go away, but you can't find the spider that you're sure is causing it. You keep at it and at it and at it ...
"Don't look, Marion!!" |
Maybe I'm growing up.....
Or maybe I have seen enough arseholes today - either works for me.
glatt Tuesday Jan 10 12:28 PM
You all are going to think I have Goatse on the brain, especially after Wolf put one of my posts in the hall of fame thread.
Anyway, I just discovered (through Boing Boing) a flickr group of images of people's reactions after seeing goatse for the first time. It's very funny. Check the flickr group out. Hell, you can even join in. Surprise friends, and submit your own pictures to flickr.
Here's a funny one:
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