31 May Kaleidoscope Effect
(GS PAPER- 3, SCIENCE AND TECHNOLOGY
SOURCE: HINDUSTAN TIMES)
Recently, people of Bangalore observed a bright rainbow ring around sun for a few seconds. This is a rare optical and atmospheric phenomenon known as Kaleidoscopic Effect which is also known as “22-degree circular halo”.
What is 22-degree circular Halo?
22-degree circular halo is observed around sun and occasionally around Moon. So, it is also called a moon ring or winter halo. This phenomenon occurs when rays from sun or moon get refracted through hexagonal ice crystals present in cirrus clouds.
Why is it called 22-degree circular halo?
Because, halo or ring forming around sun or moon has an apparent radius of 22 degrees.
Which cloud produce Circular Halos?
Circular halos are produced by cirrus clouds.
These clouds are thin, detached, hair-like clouds formed in atmosphere, at a height of 20,000 feet.
What is halo?
It is the brightest part, present at inner edge of circular disk, where there is no light inside the disk because, no light is refracted through smaller angles.