Chapter V - The Planets And Cosmology

Seven chieftains of the planets have come unto the seven chieftains of the constellations, as the planet Mercury (Tir) unto Tishtar, the planet Mars (Warharan) unto Haptoring, the planet Jupiter (Ohrmazd) unto Vanand, the planet Venus (Anahid) unto Sataves, the planet Saturn (Kevan) unto the great one of the middle of the sky, Gochihr and the thievish (dujgun) Mushpar, provided with tails, unto the sun and moon and stars. The sun has attached Mushpar to its own radiance by mutual agreement, so that he may be less able to do harm (vinas).

Of Mount Alburz it is declared, that around the world and Mount Terak, which is the middle of the world, the revolution of the sun is like a moat around the world; it turns back in a circuit owing to the enclosure (var) of Mount Alburz around Terak. As it is said that it is the Terak of Alburz from behind which my sun and moon and stars return again. For there are a hundred and eighty apertures (rojin) in the east, and a hundred and eighty in the west, through Alburz; and the sun, every day, comes in through an aperture, and goes out through an aperture; and the whole connection and motion of the moon and constellations and planets is with it: every day it always illumines (or warms) three regions (karshwar) and a half, as is evident to the eyesight.

And twice in every year the day and night are equal, for on the original attack,

when it (the sun) went forth from its first degree (khurdak), the day and night were equal, it was the season of spring;
when it arrives at the first degree of Kalachang (Cancer) the time of day is greatest, it is the beginning of summer;
when it arrives at the sign (khurdak) Tarachuk (Libra) the day and night are equal, it is the beginning of autumn;
when it arrives at the sign Vahik (Capricorn) the night is a maximum, it is the beginning of winter;

and when it arrives at Varak (Aries) the night and day have again become equal, as when it went forth from Varak. So that when it comes back to Varak, in three hundred and sixty days and the five Gatha days, it goes in and comes out through one and the same aperture; the aperture is not mentioned, for if it had been mentioned the demons would have known the secret, and been able to introduce disaster.

From there where the sun comes on on the longest day to where it comes on on the shortest day is the east region Sawahi; from there where it comes on on the shortest day to where it goes off on the shortest day is the direction of the south regions Fradadhafshu and Widadhafshu; from there where it goes in on the shortest day to where it goes in on the longest day is the west region Arezahi; from there where it comes in on the longest day to there where it goes in on the longest day are the north regions Wourubareshti and Wourujareshti. When the sun comes on, it illumines (or warms) the regions of Sawahi, Fradadhafshu, Widadhafshu, and half of Xwaniratha; when it goes in on the dark side, it illumines the regions of Arezahi, Wourubareshti, Wourujareshti, and one half of Xwaniratha; when it is day here it is night there.