B Why didn't the Moon go fully red for this eclipse?

  • Thread starter swampwiz
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(For reference, I am around coordinates ( +30 , -90 ), and this is the January 2019 lunar eclipse.)

I am typing this at supposedly mid-eclipse, and yet I see a thin crescent of white (ash?) along one side. It seems that the Moon should be well within the umbra at this point.
 

DrClaude

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@russ_watters has photographed that effect:
This is going better than I had hoped. I'm fighting a crazy 35mph wind, but still taking photos up to 1 second exposure. Here's the latest first pass processed.

View attachment 237632
Yes, it was taken right about maximum.

I was surprised to see the asymmetry. So what causes it? Is it due to atmospheric refraction bending a bit of sunlight around Earth?

[Edit; hmm, well I guess the red is too...]
 

russ_watters

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In this link, there’s a paragraph on the blue band that some folks will see due to the ozone layer refracting certain frequencies of light and that might explain what you’re seeing.

https://www.timeanddate.com/eclipse/why-does-moon-look-red-lunar-eclipse.html
They also have an animation which shows just how off center the Moon is in the Umbra;
https://www.timeanddate.com/eclipse/lunar/2019-january-21

@swampwiz thanks for starting this thread; This effect surprised me and I asked about it in my thread, not noticing you already had.
 
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Perhaps the current lack of significant stratospheric volcanic stuff ??

FWIW, I'd rather have a 'pink' Blood Moon than a Pinatubo...
 
So basically the blue band is the outer part of the umbra, and to get the full red, there must be a more central eclipse?
 

davenn

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So basically the blue band is the outer part of the umbra, and to get the full red, there must be a more central eclipse?

yes
 
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