Scientific history

Scientific history

Ibn al-Haytham's contemporary, the and polymath Ibn Sīnā (Avicenna; 980–1037), provided an alternative explanation, writing "that the bow is not formed in the dark cloud but rather in the very thin mist lying between the cloud and the sun or observer. The cloud, he thought, serves simply as the background of this thin substance, much as a quicksilver lining is placed upon the rear surface of the glass in a mirror. Ibn Sīnā would change the place not only of the bow, but also of the colour formation, holding the iridescence to be merely a subjective sensation in the eye.his explanation, however, was also incorrebn Sīnā's account accepts many of Aristotle's arguments on the rainbow

In (960–1279), a polymathic amed  (1031–1095) hypothesized—as a certain Sun Sikong (1015–1076) did before him—that rainbows were formed by a phenomenon of sunlight encountering droplets of rain in the airPaul Dong writes that Shen's explanation of the rainbow as a phenomenon of "is basically in accord with modern scientific principles.

The  and (Alhazen; 965–1039), attempted to provide a scientific explanation for the rainbow phenomenon. In his Maqala fi al-Hala wa Qaws Quzah (On the Rainbow and Halo), he "explained the formation of rainbow as an image, which forms at a concave mirror. If the rays of light coming from a farther light source reflect to any point on axis of the concave mirror, they form concentric circles in that point. When it is supposed that the sun as a farther light source, the eye of viewer as a point on the axis of mirror and a cloud as a reflecting surface, then it can be observed the concentric circles are forming on the axis.He was not able to verify this because his theory that "light from the sun is reflected by a cloud before reaching the eye" did not allow for a possible erification. This explanation was later repeated byand, though incorrect, provided the groundwork for the correct explanations later given by (1267–ca. 1319/1320) and  (c.1250–1310 Ibn al-Haytham supported the views that the rainbow is caused by reflection alone and that its colours are not real like object colours.