Nov 02, 2010
— read in fullWeird world: Rainbows
How do you get an upside down rainbow? And where’s the pot of gold?!
Why does it happen?
Upside down rainbows, or ‘circumzenithal arcs’, to give them the proper name, are not caused by rain. Normal rainbows form when light refracts through raindrops, mist, or sometimes even sea spray. The upside down kind however, are caused by ice crystals in the air. They are more common in cold climates, but still fairly rare.
Did you know?
The ‘circumzenithal arc’ is not technically a rainbow, as rainbows have to be caused by rain. Despite its similar appearance, it is actually defined as a ‘halo’ of light.
Double rainbows
Double rainbows occur when the sunlight is reflected twice inside the raindrops. The second rainbow usually sits outside the first, and looks dimmer and more blurry than the original. Because of the angle of reflection, the second rainbow appears with the opposite colour scheme to the first – Vain In Battle Gave York Of Richard!
Click here to see a double rainbow
Supernumerary rainbows
It sounds complicated, but really a supernumerary rainbow is one with smaller repeating rainbows inside it. The smaller rainbows tend not to have the same colour patterns as a normal rainbow, and the colours are lighter.
Click here to see a supernumerary rainbow
Related links
Your shout!
Have you ever seen a weird rainbow? Share your thoughts by posting a comment using the link below.
i was wondering if between the double rainbows the dark rays are the rays lower then the visible light rays?
andy jordan 23-10-11
