

Even if an observer sees another observer who seems "under" or "at the end of" a rainbow, the second observer will see a different rainbow-farther off-at the same angle as seen by the first observer. Indeed, it is impossible for an observer to see a rainbow from water droplets at any angle other than the customary one of 42 degrees from the direction opposite the light source. Thus, a rainbow is not an object and cannot be physically approached. Image of the end of a rainbow at Jasper National ParkĪ rainbow is not located at a specific distance from the observer, but comes from an optical illusion caused by any water droplets viewed from a certain angle relative to a light source. This is caused by the light being reflected twice on the inside of the droplet before leaving it. In a double rainbow, a second arc is seen outside the primary arc, and has the order of its colours reversed, with red on the inner side of the arc. This rainbow is caused by light being refracted when entering a droplet of water, then reflected inside on the back of the droplet and refracted again when leaving it. In a primary rainbow, the arc shows red on the outer part and violet on the inner side. However, the observer normally sees only an arc formed by illuminated droplets above the ground, and centered on a line from the Sun to the observer's eye. Rainbows caused by sunlight always appear in the section of sky directly opposite the Sun. It takes the form of a multicoloured circular arc. The shadow of the photographer's head on the bottom marks the centre of the rainbow circle ( antisolar point).Ī rainbow is a meteorological phenomenon that is caused by reflection, refraction and dispersion of light in water droplets resulting in a spectrum of light appearing in the sky. Double rainbow and supernumerary rainbows on the inside of the primary arc.
