• The clouds appear every day, are widespread and are
highly variable on hourly to daily time scales.
• PMC brightness varies over horizontal scales of a
few kilometers, and because of the AIM high horizontal resolution,
we now know that over small regions the clouds are ten times
brighter than measured by previous space-based instruments.
• A previously suspected, but never before seen, population
of very small ice particles was measured that is believed
to be responsible for strong radar echoes from the summertime
• Mesospheric ice occurs in one continuous layer extending
from below the main peak at 83 km up to around 90 km.
• Mesospheric cloud structures, resolved for the first
time by the CIPS imager, exhibit complex features present
in normal tropospheric clouds.