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Randomly oriented ordinary crystals can also make some
other halos in addition to 22 and 46 rings. According to
simulations the most intensive feature seems to be a
light concentration at antisolar point. This subanthelion
is brightest with cubic crystals. It is formed by two
internal reflections. With slightly plate-like crystals
also raypath of 4 internal reflections seems to light the
antisolar point. Subanthelion is obtained also with poorly
oriented columns (tilts >20 degrees).
Around antisolar point appears a broad "22 ring" and outside
"22 ring" there is a "Alexanders band". Intensities of these
features vary with the crystal aspect ratio.
These halos, especially subanthelion, may be observable from
the aeroplane (or from high tower during ice fog) when there
are strong 22 and 46 rings. If there is no 46 ring then
subanthelion is not likely to appear, since both halos need
well formed basal faces of crystals. In general, the crystals
must be in a good shape to make subanthelion. Glory and Heiligenschein
also light the antisolar point which might give some
identification problems. In plane it is good check the other
side for 22 and 46 rings.
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