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Credit & Copyright: Martin Ratcliffe
Explanation:
In this night scene from the early hours of November 14,
light from a last quarter Moon illuminates clouds above the
mountaintop domes of
Kitt Peak
National Observatory near Tucson, Arizona.
Bright Jupiter is just left of the overexposed lunar disk with
a streak of camera lens flare immediately to the right, but that's no
fireball meteor
exploding near the center of the picture.
Instead, from the roadside perspective
a stunningly bright
moondog
or paraselene stands directly over
Kitt Peaks's WIYN
telescope.
Analogous to a sundog or parhelion,
a paraselene is produced by
moonlight refracted through thin, hexagonal, plate-shaped ice crystals
in high cirrus clouds.
As determined by the crystal
geometry,
paraselenae (plural) are seen at
an angle of 22 degrees or more from the Moon.
Compared to the bright lunar disk they are more
often faint
and easier to spot when the Moon is low.
About 10 minutes after the photograph
even this bright moondog had faded from the night.
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Based on Astronomy Picture
Of the Day