- A rainbow is a colored arc in the sky, occurring when the Sun's rays shine upon falling rain. Every rainbow is a full circle; the full circle of arc cannot be seen from the ground but may be
observed from an airplane. The center of the circle is always at a point in the sky opposite the Sun. The size of the visible portion of the rainbow depends on the altitude of the Sun.
A rainbow exhibits the colors of the spectrum--the inner part is always violet and the outer red. Occasionally a second, larger, dimmer arc is seen with the colors reversed, because of a double reflection within the drops.Links to more indepth pages about rainbows:
Rainbows
Rainbows.html
Rainbow InformationThe information about rainbows was found in:
1998 Grolier Multimedia Encyclopedia
Microsoft Encarta Encyclopedia 99