Midrash su Salmi 147:17

The aperture which is in the midst of the firmament is named M'zarim and (the sun) does not go forth or set therein except once in its great cycle; (thereon) it goes through it as on the day when it was created. At night the sun is in the west. At the Teḳuphah of Tishri and at the Teḳuphah of Ṭebeth the sun goes on its course in the south quarter and in the waters of the Ocean (which are) between the ends of the heavens and the ends of the earth where it is submerged. For the night is long and the way is long until (the sun) reaches the aperture which is in the east, (even) the aperture through which it desires to go forth, as it is said, "It goeth toward the south, and turneth about unto the north" (Eccles. 1:6). It goes to the south at the Teḳuphah of Tishri and at the Teḳuphah of Ṭebeth, and turns to the north at the Teḳuphah of Nisan and at the Teḳuphah of Tammuz. It goes on its course for six months in the south quarter, and for six months in the north quarter, and owing to its circuits the sun returns to the aperture which is in the east. The sun has three letters of (God's) Name written upon his heart, and the angels lead him; such || as lead him by day do not lead him by night, and such as lead him by night do not lead him by day. The sun rides in a chariot and rises, crowned as a bridegroom, as it is said, "Which is as a bridegroom coming out of his chamber, and rejoiceth as a strong man to run his course" (Ps. 19:5). The sun's rays and face, which are turned downwards (to the earth), are of hail; and were it not for the hail which quenches the flames of fire the world would be consumed by fire, as it is said, "And there is nothing hid from the heat thereof" (Ps. 19:6). In winter (the sun) turns the upper (half of) his face downwards, and were it not for the fire which warms the face of hail the world could not endure because of the ice (cold), as it is said, "Who can stand before his cold?" (Ps. 147:17). These are the ends of the ways of the sun.