If you looked up at the sky on Monday [October 26] at midday and saw an unusual ring around the sun, it wasn’t a sign of life on other planets or something unearthly. Instead, it is a natural phenomenon which scientists call a 22 degree halo, mostly because the ring around the sun or moon has an approximate radius of 22-degrees.
It is a housewife’s tale that if you see the ring around the sun or moon, you can anticipate rainfall soon after. Judging by Tuesday’s gloomy weather, it might not be a fable after all.
What causes a sun halo?
It is created by the reflection, refraction and dispersion of light that flows through ice particles which are suspended in wispy cirrus or cirrostratus clouds. When the light travels through the ice-crystals, which are hexagon-shaped, they bend at an angle of 22-degrees thus creating a ring around the sun called a halo. If you see different colours within the halo, it is due to the prism-effect of light passing through the ice crystals.
