What is the hymn that gives the "exact" date of Sun going down the horizon? Now this is fun.Actually, RigVeda gives us the exact date when the sun went down the horizon. It was the fortieth of Sharadi. That is the fortieth day from the autumnal equinox or 10th in the eighth month. That would correspond to October 10, when the verse says Indra found Shambara, one of the demons of darkness, in his fort. RigVeda is exact history. That is why Martanda was considered to be unformed while seven others were fully formed.