Part of a double rainbow seen here in Singapore after the heavy rain had stopped. The primary rainbow is the lower one with distinct colours while the fainter rainbow is the secondary one. If one look closely , the colour sequence of the secondary rainbow is opposite to that of the primary rainbow. Red colour is on on the inside and violet on the outside When light reflects twice off the back of raindrops, it leads to the secondary rainbow. The second reflection causes the reversal of the order of the colours in the rainbow.