Though light pillars are often caused by artificial light, sun pillars, as in the above picture, occur when sunlight reflects off the facets of millions of flat ice crystals in very cold air.

• 虽然光柱往往是人工光源造成，如上述图片，当阳光在极冷的空气中从侧面通过数以百万计的单位冰晶反射便形成了太阳光柱。