Venus Sign Calculator (plus Mars & Mercury Signs and Retrogrades)

How it works

Heliocentric orbit of the planet and of Earth from Keplerian elements (JPL, Standish) → solve Kepler's equation E − e·sin E = M → rotate into ecliptic coordinates · geocentric longitude λ = atan2(y_planet − y_Earth, x_planet − x_Earth), corrected for light time, precession to the date, aberration and nutation · sign = ⌊λ ÷ 30°⌋; retrograde when λ is decreasing

Your Venus sign is the zodiac sign Venus occupied, as seen from Earth, when you were born. Venus stays in a sign for about 4–5 weeks (up to 4 months when it turns retrograde), Mars for about 6–7 weeks and Mercury for 2–3 weeks, so the birth date is normally enough and the time only matters near a sign change. The calculator computes the planets' positions from NASA JPL orbital elements — within a few arc-minutes of professional ephemerides for 1800–2050. Astrologers link Venus to love and taste and Mars to drive; those meanings are entertainment, not science.

Worked example

For a birth on May 15, 1990 at 12:00 in Mexico City (UTC−6), Venus was at 13.11° of ecliptic longitude, 13°06′ Aries — a Venus in Aries, fire element, moving direct. Venus entered Aries on May 3, 1990 and left it on May 30, 1990. In the same chart the Sun is in Taurus, the Moon at 0°16′ Aquarius, Mercury in Taurus (retrograde) and Mars in Pisces.

Sources: NASA JPL — Approximate positions of the planets (Standish) · Meeus, Astronomical Algorithms (2nd ed.), ch. 33

Frequently asked questions