Resources
Guides to the zodiac itself: why sign dates move from year to year and what a cusp really is, how the four elements and three modalities organise the twelve signs, and why the tropical zodiac does not follow the constellations.
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Zodiac sign dates and cusps: why your sign can switch on the 19th–23rdWhy your zodiac sign can change on the 19th to 23rd, the real start-date spread of all twelve signs and how to settle a cusp birthday.7-minute read
Elements and modalities: the 4x3 grid that organises the twelve signsFour elements times three modalities gives the twelve signs once each: the grid, the arithmetic behind trines and squares, and the rulers.7-minute read
Tropical vs sidereal zodiac and Ophiuchus: did your sign change?Why the tropical zodiac sits about 24° from the stars, what sidereal astrologers do instead and why Ophiuchus is not a thirteenth sign.6-minute read