Find the actual date when the Sun moves in a Zodiac constellation

On the calendar chart below, the tropical (western) astrology star-sign dates are indicated on the rim, on a purple base, next to the months. The star positions of the Zodiac constellations are illustrated on the chart's centre. The Zodiac constellation positions are plotted using precise astronomy data. On the pink base, the names of the Zodiac constellations are aligned with the actual position of the constellations. Notice the astrology calendar star-sign dates, in purple, are as much as a month out of alignment with where the actual constellations are located, indicated on the pink rim.

On the calendar chart below, refer to the Zodiac names on the pink rim to find when and where the Sun moves in a Zodiac Constellation. From a selected date, trace towards the centre, to where the ecliptic and the dateline cross a constellation area.

To find where the Sun was when you were born and will be every year on your birthday, trace from your birth-date on the calendar towards the ecliptic. The constellation that the Sun is on your birthday indicates your actual star sign.