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- thin Altostratus
- major part of the layer is sufficiently thin to reveal the position of the sun (no Halo )

graphic

graphic

graphic
note in this picture also some Stratocumulus below Cm 1


graphic

from the top downward:
photo by B. Muehr
photo by Kruegler
photo by R.K. Pilsbury (Crown copyright)
photo by Kruegler