Vishnupurana 2.8.p7

2.8.p7

The radiance of the sun, after its setting, is deposited in fire and hence fire is visible even at a greater distance in night. During day the rays of fire enter into the sun by virtue of which the sun becomes more brilliant. Elemental light and heat, proceeding respectively from the sun and fire and mixing with each other, prevail in diverse degrees both by day and night. When the sun prevails either in the northern or southern hemisphere day or night goes into waters according as they are attacked by darkness or light; it is for this reason that waters appear dark by day because night is within them and white by night because when the sun is set the light of the day enters therein.