Who among us has not seen the arch of a rainbow during or after the rain? This phenomenon is caused by the refraction and reflection of sunlight in drops of water, very often makes passerby just to note to myself: «Oh, rainbow». But to get to stop any of us, exclaiming «Wow, what a rainbow!», and forget about everything in the world is capable of only a phenomenal spectacle, like kalogeropoulou arc, known as the «fire rainbow».
Witness is such an optical illusion during your jog on the trail at Pinnacle this week was Michael Jimenez, a photo of which was published in the NWS Bay Area Twitter.
A «Fire Rainbow» 🔥🌈 was captured over @PinnaclesNPS yesterday. The more scientific name is a circumhorizontal arc. For more details https://t.co/VYycZRvrAu #cawx #atmoshpericoptics 📸 M. Jimenez pic.twitter.com/FwkjZuthJe
— NWS Bay Area (@NWSBayArea) April 25, 2018
Fire rainbow the more surprising for the average man that it is possible to observe only in clear weather and in a certain latitude. The approximate range of manifestations of this phenomenon — from the equator to 55° North and South latitudes. With latitudes, residents of the United States are more fortunate than others: here, this type of rainbow — a very common summer phenomenon.
In spite of this, to witness firsthand the «burning» clouds can not every American, after all, for the manifestation of such illusions need a combination of several natural factors:
 the high location of the sun from 57.8 ° above the horizon;
 the presence in the sky of Cirrus clouds (they are light and are highly);
 the ice crystals that make up these clouds, should be placed with their faces parallel to the ground.
Difficult? Who knows, maybe this summer the stars will be favorable and you will become a witness of how the sun «lights» of the cloud.
