High-altitude pyramid column arcs and kaleidoscope sky （6 May，China）

 Every year from March to May seems to be the pyramid column arcs' season for China. In the 2024 season, the most eye-catching display occured on 6 May, ChangSha, HuNan Province. At altitude of about 71.3°, the Pyramid column arcs, PC and Wegener crossed each other, bringing a spectacular picture of the sky.

(张晖)ZHANG Hui's stack image through a stack of 112 photos spanning 10 minutes. BGR and USM processes make arcs clearer.

Below are the results of a preliminary simulation using ZHANG Jia Jie 's program.

Well, now we are already looking forward to the second half of the year. Unlike March to May, June to August seems to be the peak time for pyramid plate arcs and 28° arcs for China. Please wish us luck.

JI Yun