♈ Aries — ecliptic 0° to 30°

The birth-chart calculator treats 0° as the start of the tropical zodiac, not as a personality score. A Sun at 14.2° is still inside Aries. The next integer boundary, 30.0°, is the first degree of Taurus. That single cut is why a birthday on 19 April and a birthday on 20 April do not share a sun-sign page on this site: the longitude has crossed a 30° sector.

Mars is the ruler stored for Aries. Rulership is not a sky position. The sky table further down lists whichever planets are actually inside 0°–30° at the observation time, from Paris. Mars can rule Aries while sitting in another sign entirely. Cardinal fire is also exclusive: Leo is fixed fire and Sagittarius is mutable fire, so “fire sign” alone describes three different windows.

From the Aries center at 15° to the Libra center at 195°, the separation is 180°. The engine calls that an opposition and allows an orb of 8° when two planets are compared. Leo and Sagittarius fall at 120° (trine, orb 8°). Cancer and Capricorn fall at 90° (square, orb 8°). Gemini and Aquarius fall at 60° (sextile, orb 6°, the only major aspect in this engine with a 6° allowance). Pisces and Taurus are 30° away. Virgo and Scorpio are 150° away. Neither 30° nor 150° sits inside any orb the aspect table uses, so those pairs are not major aspects here. A sun sign still does not give the Ascendant: that angle needs a birth time because it moves about every two hours.