2006. május 13., szombat

Doubled Halos?

This image was taken in Fukushima pref. in Japan, by Mr. Tasan (handle), May 5, 2006. There are two halos -- the lower one seems a 22 degree halo, but what is the upper one? I think it can be a 24 (or 23?) degree halo, a circular Lowitz arc or a 23 degree plate arc. What are your opinions?

3 megjegyzés:

  1. Interesting there I think by the looks of that diffuse arc I think its upper 23 degree plate arc.

  2. Yeah, looks like a upper 23 plate arc. Parry or Lowitz would be expected to be sharper. The halo below can be either 23 halo or 22 halo. Pyramid crystals usually have such a large tilt that 23 halo is produced below 23 plate arc. But here it looks like there is bit of a pooly developed tanget arc look in the halo below, so I think it's 22 stuff. Knowing sun elevation might give us more definitive answer.

  3. Sorry for lacking information about solar elevation etc.
    The elevation is about 40-degree or little bit less.
    At that time, he saw only those two arcs,
    but a parhelion and a circumzenithal arc was seen
    after an hour.