Tuesday, November 19, 2013

Earth's approaching shadow visible at twilight.


Via APOD, from central Australia, this serene 360 degree panorama follows a clear horizon as twilight began on May 28. At left, a bright western sky is still illuminated by the setting Sun. But sweeping right, toward a view centered on the countryside's dominating sandstone Ayers Rock, the sky takes on progressively darker hues and subtle colors. Behind  is the shadow of planet Earth itself, a dark blue arch rising in the east. Cast through the dense atmosphere and still close to the horizon, Earth's long shadow is bounded above by a pinkish glow or antitwilight arch. Known as the Belt of Venus, the lovely color of the antitwilight arch is due to backscattering of reddened light from the setting Sun.

I have never seen this.  Now I'm going to have to constantly look for the shadow.

2 comments:

  1. Never heard of this phenomenon, but I will now be constantly searching, too. Thanks. :-)

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    1. I think we'll need to find a spot where it's flat to the horizon to maximize our chances. The midwest plains states would seem to be near to perfect

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