Explanation:
What's happening over that town?
Close inspection shows these strange columns of light occur over bright lights, and so likely involve falling
ice crystals reflecting back these lights.
The reason why these pillars fan out at the top, however, is currently unknown --
readers of APOD might help figure this out by participating in an
online discussion.
The
above image and several similar images were taken with a standard digital camera in
Sigulda,
Latvia last month.
The air was
noted to be quite cold and indeed filled with small ice crystals, just the type known to create several awe-inspiring but well known
sky phenomena such as
light pillars,
sun pillars,
sun dogs, and
moon halos.
The cold and
snowy winter occurring this year in parts of Earth's northern hemisphere is giving
sky enthusiasts new and typically unexpected opportunities to see several of these unusual optical
atmospheric phenomena for themselves.
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