▁water ▁prevents ▁light ▁from ▁being ▁devi ated ▁at ▁smaller ▁angles . ▁ ▁The ▁minimum ▁deviation ▁angle ▁for ▁the ▁primary ▁bow ▁is ▁ 1 3 7 . 5 ° . ▁Light ▁can ▁be ▁devi ated ▁up ▁to ▁ 1 8 0 ° , ▁causing ▁it ▁to ▁be ▁reflected ▁right ▁back ▁to ▁the ▁observer . ▁Light ▁which ▁is ▁devi ated ▁at ▁intermediate ▁angles ▁bright ens ▁the ▁inside ▁of ▁the ▁rain bow . ▁ ▁The ▁minimum ▁deviation ▁angle ▁for ▁the ▁secondary ▁bow ▁is ▁about ▁ 2 3 0 ° . ▁The ▁fact ▁that ▁this ▁angle ▁is ▁greater ▁than ▁ 1 8 0 ° ▁makes ▁the ▁secondary ▁bow ▁an ▁inside - out ▁version ▁of ▁the ▁primary . ▁Its ▁colors ▁are ▁revers ed , ▁and ▁light ▁which ▁is ▁devi ated ▁at ▁greater ▁angles ▁bright ens ▁the ▁sky ▁outside ▁the ▁bow . ▁ ▁Between ▁the ▁two ▁b ows ▁lies ▁an ▁area ▁of ▁un lit ▁sky ▁referred ▁to ▁as ▁Alexander ' s ▁band . ▁Light ▁which ▁is ▁reflected ▁by ▁ra ind ro ps ▁in ▁this ▁region ▁of ▁the ▁sky ▁cannot ▁reach ▁the ▁observer , ▁though ▁it ▁may ▁contribute ▁to ▁a ▁rain bow ▁seen ▁by ▁another ▁observer ▁elsewhere . ▁ ▁References ▁ ▁External ▁links ▁ ▁Category : At mos pher ic ▁optical ▁phen omena ▁ ▁de : Alex and ers ▁d unk les ▁Band ▁fr : Ar c - en - ci el # La ▁bande ▁som bre ▁d ' Alex and re <0x0A> </s> ▁George ▁P enne father ▁( 2 8 ▁September ▁ 1 8 6 4 ▁– ▁ 1