© Mila Zinkova
San Francisco, California, United States of America
Latitude: 37° 45' 55'' N
Longitude: 122° 30' 44'' W
23 February 2016 1516 (Local Time)
Image P/S code: P.13.1.1.1
Image I.D.: 4658

On rare occasions, circular halos may appear that are not produced by the more common hexagonal prism ice crystals and they have radii that are not the “typical” 22° and 46°. Such rare circular halos of non-typical radius are produced by pyramidal ice crystals.
This picture from San Francisco, California, USA, shows a series of circular halos. The innermost halo has a radius of 9°. There is also an 18° halo together with halos of other radii.
Links in the image description will highlight features on the image. Mouse over the features for more detail.