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

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    Eclipse Moon
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Discussion Overview

The discussion revolves around the observations and explanations regarding the lunar eclipse that occurred in January 2019, specifically why the Moon did not appear fully red during the event. Participants explore various factors that could influence the color and visibility of the Moon during the eclipse.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant notes seeing a thin crescent of white light during the eclipse, suggesting that the Moon should be fully within the umbra.
  • Another participant references a source discussing the blue band effect caused by the ozone layer refracting certain light frequencies, which may explain the observed crescent.
  • A participant shares their experience photographing the eclipse and expresses surprise at the asymmetry of the Moon's appearance, questioning whether atmospheric refraction is responsible.
  • There is a suggestion that the lack of significant stratospheric volcanic activity might contribute to the color of the Moon during the eclipse.
  • Some participants discuss the relationship between the position of the Moon within the umbra and the intensity of the red color, indicating that a more central position might yield a fuller red appearance.
  • One participant humorously mentions a meteor striking the Moon during the eclipse, adding an unexpected element to the event.

Areas of Agreement / Disagreement

Participants express various hypotheses regarding the color of the Moon during the eclipse, with no clear consensus on the primary reasons for the observed effects. Multiple competing views remain regarding the influence of atmospheric conditions and the Moon's position in the umbra.

Contextual Notes

Participants reference external sources and animations to illustrate their points, indicating that the discussion is informed by visual aids and additional literature. There is mention of potential limitations related to atmospheric conditions and the specifics of the eclipse's geometry.

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.
 
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@russ_watters has photographed that effect:
russ_watters said:
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

russ_watters said:
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...]
 
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jedishrfu said:
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.
 
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?
 
swampwiz said:
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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