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.
Sunlight contains all colors (seen in the famous rainbow, or with a prisma), and for each angle there's one color which interferes constructively, while the others do less so. Therefore each point on the puddle seems to have a certain color. And it shifts when you move your head.