Or Sun reaching his Maximum Declination, Ravi Parama Kranti of 23 D 27 M ?
While reaching Karkyadi, Sun initiates Ramayana Masa, Kataka Masa, which calls for Morning and Evening Hymns of a high order.
It is called Ramayana Masa, because it invokes the Greatest of All Exemplars. Lord Rama !Lord Buddha & Lord Rama had everything to renounce, while Lord Jesus Christ had nothing to renounce.