1 Anaphylaxis is the most severe allergic reaction and is potentially life threatening. 2  Anaphylaxis is rare. The vast majority of people will never have an anaphylactic reaction.  Common triggers of an anaphylactic reaction include drugs, such as penicillin, insect stings, foods (peanuts, shellfish), X-ray dye, and latex.
A rainbow has depth to it, all along the radius refraction angle of 45 degrees. A halo around the moon on vaporous clouds has red and magenta on the outside, the yellow is minor, green and cyan are the inside colors. The lighter area is to the inside. A moon bow is magenta, white, green, and rare.
When light meets a water droplet, it is refracted at the boundary of air and water, and enters the droplet, where the light is dispersed into the seven colors. The rainbow effect occurs because the light is then reflected inside the droplet and finally refracted out again into the air.