Rainbow

A Rainbow is not an object and cannot be physically approached.A rainbow is a phenomenon that is caused by reflection, refraction and dispersions of light in water droplets resulting in a  spectrometer  of light appearing in the sky.Rainbows can be full circles. 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.It comes from an optical illusion caused by any water droplets viewed from a certain angle relative to a light source. Rainbows can be observed whenever there are water drops in the air and sunlight shining from behind the observer at a low altitude angle. Because of this, rainbows are usually seen in the western sky during the morning and in the eastern sky during the early evening.VIBGYOR IS the form to remember colours of RAINBOW