The dominant planet is triggering much interest with 12andus' users. Several users recognized themselves in the dominant planet descriptions and have asked me to tell more about it. Other users asked why the dominant planet displayed in 12andus is different from the one calculated on other astrological sites.

The dominant planet calculation is not an objective procedure. Each astrologer might consider different parameters and give different weight to such parameters, resulting in a different dominant planet, even though the differences shouldn't be too big.

The so-called sign astrology was created as entertainment by newspapers and there isn't much based on that, since the sign is only about the position of the Sun at birth. A natal chart is made by tens of elements interacting with each other. The sign is an oversimplification.

I feel that slowly the concept of "sign" will give space to the concept of dominant planets. Nowadays, everybody can have an Internet connection to know more about their natal chart. It will take probably a generation or 2, but this is the direction things are going in.

The main parameters we consider for calculating the strength of each planet is:

- The aspects with other planets and with the Ascendant or Medium Coeli. As more of the aspect is closer to the exact aspect, the strength of the aspect increases. Conjunctions are stronger than other aspects. Trine or opposition aspects come next, then squares or sextiles, and then minor aspects.

- We set the orbs according to a number of parameters: the planets (or Ascendant/Medium Coeli) involved, the type of aspect and the houses where the planets are. At 12andus we use wider orbs than average. We believe, as some astrologers do, that there's no such thing as an "orb" of influence. However, we calculate the power of an aspect proportionally to how close the orb is to the exact aspect. Even though an aspect with a very wide orb would be considered very weak (and thus will poorly contribute to the dominant planet calculation), we think it is worth to also mention the presence of a loose aspect.

- The sign where the planet is. Every planet feels more at home and expresses itself better in certain signs. Planets in domiciles or exaltation get more power. For instance, Mars' domicile is in Aries, Mercury's domicile is in Geminis, the Moon's exaltation is in Taurus and the Sun's exaltation is in Aries. When the planets happen to be in a sign which valorizes and expands their nature, then we give more value to the planet.

- The distance from the cusp of the house. As it gets closer to the cusp, the more powerful the planet gets. If the planet is in one angle house (1st, 4th, 7th or 10th house), the planet is more powerful.

- The house where the planet is located also gives it "points." For instance, Saturn would be more at home in the 10th house, Venus in the 7th house, Mars in the first house and so on.

- "Mutual receptions." This happens when a planet is in the domicile or exaltation of another planet and vice versa. As an example, Venus in Capricorn (home of Saturn) with Saturn in Pisces (where Venus is exalted), gives several more "points" both to Venus and Saturn.

Then we fine tune those parameters according to the subtle interactions between planets, aspects, signs and houses.

All in all, our dominant planet calculator can't be objective because there isn't a dominant planet procedure which is agreed upon among astrologers, but up until now, it is the best approximation we could envision.

Another astrology site might give different weight to some other parameters, or even not consider some of them. This will reflect in a different position of the planet in the score of the most important planets in the chart.

As much as the dominant planet is important, we should not forget that the co-dominant planet, the second most important planet, also shapes our chart and traits.

Register to 12andus to learn about your natal chart and your transits with free, in-depth personalized reports.

To discover your dominant planet, go to the Astro Reports section and click on the "Birth chart's answers" box. There are 3 boxes dedicated to your dominant planet with comprehensive interpretations.

See also:

What does your dominant planet say about you?

The Sun as the dominant planet: generosity, charisma, confidence

The Moon as the dominant planet: sensitivity, support, imagination

Mercury as the dominant planet: intuition, communication, restlessness and mutability

Venus as the dominant planet: love, harmony and arts

Mars as the dominant planet: action, passion and competition

Jupiter as the dominant planet: expansion, philosophy and generosity

Saturn as the dominant planet: discipline, responsibility, long term planning

Uranus as the dominant planet: freedom, originality and being unconventional

Neptune as the dominant planet: sensitivity, intuition, spirituality

Pluto as the dominant planet: power, sexuality, depth