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Finding the location of the sun in the zodiac

Finding the location of the sun in relation to the fixed stars is the key to solving problems related to time later on. Throughout the year, the sun slowly moves along the ecliptic through the constellations of the zodiac. Each constellation is divided into thirty degrees. Since their are twelve constellations of the zodiac, the ecliptic is divided into three hundred and sixty degrees. This allows us to determine the position of the sun to within at least one degree with respect to the stars. The back of the astrolabe will help us determine where the sun is. Simply line up the alilade with the date on the calendar scale. Whatever position is indicated on the zodiac scale by the edge of the alilade is the current position of the sun. This information will allow us to locate the sun on the ecliptic scale of the rete.

Example: Where is the sun on the 2nd of August? Using the back of the astrolabe, line up the alilade so that its inner edge rests against the 2nd of August on the calendar scale (see below). On the zodiac scale, the edge of the alilade lies on the 10th degree of Leo (notice that each constellation is divided into thirty degrees.) Thus we say that the sun is in the 10th degree of Leo on the 2nd of August. Now we are able to locate the sun on the ecliptic circle of the rete for problems involving the sun. You can repeat this procedure for any date of the year. Try it for your birthday to confirm your astrological "sign."