Rainbow. It is an arc of concentric bands of light in the colours of the spectrum. It is seen in the sky when the Sun is behind the observer and raindrops are in front. The separation of the colours is caused by the reflection and refraction of the sunlight in the water drops. The larger the drops,the brighter are the colours. A faint secondary rainbow is sometimes visible above the primary one. In the primary rainbow the Sun's rays experience only one reflection in the water drops,whereas the secondary rainbow is caused by those rays which undergo two reflections. This also causes the reverse order of the colours in the two rainbows | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / PEKKA PARVIAINEN |
Taille de l’image : | 3115 px × 4605 px |
Model Release : | Non requis |
Property Release : | Non requis |
Restrictions : | - |