cubinator

Lunar Eclipse January 20-21 2019

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Turns out that it was very foggy at the time of totality. Of course it cleared up once the Moon started to get out of Earth's shadow.
Also, the camera that I was using, an old Olympus, requires its own USB cable to get them on the PC. So it may take a few days until you can see mine.

And I took some! Not professional of course and most of them are overexposed, but it's fine.

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2 hours ago, cubinator said:

Here comes the sun again!

Spoiler

 

 

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Images cropped, raw, unsharpened:

btRHttl.jpg

X3g3GD3.jpg

I made a sequence as well, but give me some time to prepare it.

 

I found this one extremely impressive, as it happened totally during night, the weather was extremely clear, and the stars came out like in a moonless night. Unfortunately a fierce and gusty wind was blowing due to a foehn effect on the leeward side of the island. That's the cause of the  blurryness. Images taken with 100ASA, f/8, 16/32sec. Hastily adjusted equatorial mount.

Edited by Green Baron
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I tried to see it, but it wasn't easy.  Way too dim to see the moon clearly. :(

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The clouds broke up enough around midnight I got to see a lot of it!  :D

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Saw the partial pretty well, but we had a thin veil of high alt clouds, so while the partial was visible the whole time, the Moon became nearly invisible once it was in the Umbra.

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Saw it as well, early in the morning at 6:00am

I had a dream about the moon blowing up that night so that was funny.

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I can't believe!, that I just now heard on the news an announcer (out in CA) explaining how the moon was red because of the Sun's light passing through the Earth's "polluted atmosphere".

Nevermind clueless;  Hopeless.  Absolutely hopeless.  :mellow:

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Small particles in the atmosphere do influence the atmospheric scattering. Pollution (for example from plinian eruptions) does make a difference. Without particles the effect would be much weaker.

I have a direct comparison between southern Germany (Stuttgart area) where a constant red haze from dust and particles (mostly man made pollution) limits night sky/star visibility most time of the year to above 20-30° over the horizon, and here (Atlantic island), where stars actually frequently set on the horizon (sea).

It is the same effect that makes the moon reflect the red light from light that has traveled through earth's atmosphere.

https://en.wikipedia.org/wiki/Rayleigh_scattering

But i don't know if the guy had that in mind ;-)

Edited by Green Baron

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Yes, pollution does make the light redder, but the Moon is always red during such am eclipse because it's mainly the same scattering you see in a sunset which is hitting it. Pollution isn't the cause of that.

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But a sunset in clear air would not be red, air is blue. Well, absolutely clear air doesn't exist on earth and that makes the sunsets reddish, but here we frequently have sunsets that aren't even orange to the last moment and you can't look directly into the sun until it is gone and leaves a dark blue sky behind.

And the moon isn't always that red. It can have other hues like ocre depending on particles in the earth's atmosphere. It actually can be blue (look at the pictures above) there where it is hit by light that traveled through the upper atmosphere, where ozone filters out the reddish wavelengths.

Small particles in the lower atmosphere are the main cause of a more or less red sunset. Which is a measurable effect, and it is stronger in densely populated areas or where weather blows dust around, or after huge eruptions (I recall Pinatubo and Mt. St. Helens). Citing this Nasa text: "How gold, orange, or red the Moon appears during a total lunar eclipse depends on how much dust, water, and other particles are in Earth's atmosphere, as well as factors such as temperature and humidity."

It is not completely wrong to name pollution here, though the effect of a reddish moon during the total eclipse would of course be there from just the earth's air O and N molecules as well.

Edited by Green Baron
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The amount of effect pollution plays here is nearly of no consequence, and really isn't even a factor in the explanation of 'why'.  The explanation of why is 'Rayleigh scattering', not 'passing through polluted atmosphere' ... unless of course you've got an agenda, which of course ..........

 

Hopeless.  Absolutely hopeless. 

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Here's a few that my amateur hand took with my Canon EOS Rebel T5i. I really need to get a tripod. I experimented with a variety of settings. I'd post more, but time is limited. Cropped, but otherwise raw.

Spoiler

As it started...

Gig9SUR.jpg

And then later...

subs3jw.jpg?1

39S5EIs.jpg?2

E: The local radio made the point of "just find an eclipse someone posted online, save it, and post it on FB as your own. Who's gonna know the difference?"

 

Edited by StrandedonEarth
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26 minutes ago, StrandedonEarth said:

The local radio made the point of "just find an eclipse someone posted online, save it, and post it on FB as your own. Who's gonna know the difference?"

That's silly.  Who would do something like that?

 

Meanwhile, I managed to capture these cool images:
 

Spoiler

Gig9SUR.jpg

subs3jw.jpg?1

39S5EIs.jpg?2

 

27 minutes ago, StrandedonEarth said:

Who's gonna know the difference?

Hehehehehehe.

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2 hours ago, StrandedonEarth said:

Who's gonna know the difference ?

There's something called EXIF.

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6 minutes ago, YNM said:

There's something called EXIF.

EXIF is good, but I use EXIV2 ... it's especially handy for bulk image file renaming when one wants all the files in a directory named as 'date.time' when taken.  My digital camera was a real pain in that all the images were 'image01 image02 image03 etc', and the option was to reset the counter after each upload or let the numbering run up.  Pain in the butt.  This makes far more sense, and makes for easier handling (for me anyway). ^_^

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2 hours ago, LordFerret said:

makes for easier handling

We just need the metadata stamps off the camera anyway.

(and yes imgur and other sites that hosts image on the internet and gives a reduced resolution usually gets rid of this metadata)

Edited by YNM

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7 hours ago, LordFerret said:

The amount of effect pollution plays here is nearly of no consequence, and really isn't even a factor in the explanation of 'why'.  The explanation of why is 'Rayleigh scattering', not 'passing through polluted atmosphere' ... unless of course you've got an agenda, which of course ..........

 

Hopeless.  Absolutely hopeless. 

Mate, you have posted an inflammatory post two times now and you reject explanations from observation and experiment. Particle sizes including (but not limited to) pollution do influence the colour and it is not "hopeless" to name that, unless you follow an agenda !

You can make an experiment and travel for example to the Colorado plateau where the air is clear because it is isolated from the circulation and inflow of pollution by mountain ranges and convince yourself that a clear air sunset is not red. The eclipsed moon can have other hues than "blood" red, even blue. Rayleigh scattering depends on particle sizes, and the amount of pollution (natural or artificial) is decisive in the colour giving, and it is not wrong and by no means "hopeless" to name that.

 

Edit: reasonable pop science on the matter:

https://www.sciencenewsforstudents.org/article/2019-total-lunar-eclipse-could-be-beet-red-because-volcano

 

Edited by Green Baron

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1 hour ago, Green Baron said:

total-lunar-eclipse-could-be-beet-red-because-volcano

... and they said it went blue during Krakatau's 1883 explosion ?

Edited by YNM

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Where ?

Giving the right particles this may have been the case, locally temporarily. Am thinking about sulfuric aerosols that filter out infrared, but that should be checked. Though reports from the northern hemisphere talk about nice red/brown sunsets in the years following the eruption. Tambora eruption may even have had an impact on art (William Turner (not the pirate ;-))) Sky colour may vary with time and composition.

Anyway, it is pretty obvious that pollution does change atmospheric scattering, locally, regionally and globally.

 

Edited by Green Baron

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2 hours ago, Green Baron said:

Giving the right particles this may have been the case, locally temporarily.

idk, it is often said that blue moon occurs when there's a lot of haze in the area, incl. the right kind of forest fires and various volcanic ash.

Would make sense that an eclipse in those conditions be rendered blue-red... purple ? magenta ?

And no these usually occur on the subtropic latitudes, as near the volcano itself the ash are dispersed away very quickly or falls much faster.

Edited by YNM

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I'll say it again... " The explanation of why is 'Rayleigh scattering', not 'passing through polluted atmosphere' "

From the Wiki link you've posted

Quote


... is the predominantly elastic scattering of light or other electromagnetic radiation by particles much smaller than the wavelength of the radiation. Rayleigh scattering does not change the state of material and is, hence, a parametric process. The particles may be individual atoms or molecules. It can occur when light travels through transparent solids and liquids, and is most prominently seen in gases. Rayleigh scattering results from the electric polarizability of the particles. The oscillating electric field of a light wave acts on the charges within a particle, causing them to move at the same frequency. The particle therefore becomes a small radiating dipole whose radiation we see as scattered light. This radiation is integral part of the photon and no excitation or deexcitation occurs.

Rayleigh scattering of sunlight in Earth's atmosphere causes diffuse sky radiation, which is the reason for the blue color of the daytime and twilight sky, as well as the yellowish to reddish hue of the low Sun.

For wave frequencies well below the resonance frequency of the scattering particle (normal dispersion regime), the amount of scattering is inversely proportional to the fourth power of the wavelength.

Rayleigh scattering of molecular nitrogen and oxygen in the atmosphere includes elastic scattering as well as the inelastic contribution from rotational Raman scattering in air, since the changes in wavenumber of the scattered photon are typically smaller than 50 cm−1.[2] This can lead to changes in the rotational state of the molecules. Furthermore, the inelastic contribution has the same wavelengths dependency as the elastic part.

Scattering by particles similar to, or larger than, the wavelength of light is typically treated by the Mie theory, the discrete dipole approximation and other computational techniques. Rayleigh scattering applies to particles that are small with respect to wavelengths of light, and that are optically "soft" (i.e., with a refractive index close to 1). On the other hand, anomalous diffraction theory applies to optically soft but larger particles. ...

 

 

I don't see anything about pollution in there.  The answer to the question is 'Rayleigh', not 'pollution'.

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