Your natal chart (or any astrology chart) consists of placements and aspects. This page is an introduction to chart reading that will help you learn how to determine what your chart means. It also covers the difference between modern and Hellenistic astrology.

What are placements?

A placement is a planet or other chart point in a sign (Aries, Taurus, etc) and house (1st-12th). A placement sounds like this: "My Venus is in Cancer in the 8th house". The meaning of a placement is determined by synthesizing the symbolic meanings of each component together into a cohesive interpretation.

Do I need my birth time to know my placements?

You can determine certain things about your placements without a birth time, but not your rising sign, house placements, and often the moon sign will not be certain without a birth time.

To learn what signs most of your planets are in, usually the birth date is sufficient. The exceptions are if a planet is very close to a sign boundary (at 0 or 29 degrees). The Moon moves quickly and it changes signs every few days so being born in the morning or evening could mean a different moon sign.

Houses are based on the Earth’s daily rotation so they change every 2 hours. This means you must have an accurate birth time, to know your correct rising sign and houses.

What is a “rising sign”?

Your rising sign or Ascendant is the exact degree of the sign that was on the eastern horizon when you were born. The sign that is rising changes every two hours, which is why you need your time of birth to determine your rising sign.

The signs are each 30 degree segments on a circle that is formed by the path of the Sun through the sky (called the ecliptic). The whole wheel turns as the Earth spins, and each part of it rises just like the Sun does every morning.

If this is confusing, think of it this way: you know from looking at horoscopes that the Sun is in every sign for about a month. Think of what sign the Sun is in currently. Wherever the Sun is in the sky right at this moment— that’s where that sign is as well.

What are aspects?

An aspect is a geometric relationship between two planets or points on your chart. Different degree angles have different names. (0°=conjunction; 90°=square; 180°=opposition, etc) An aspect sounds like this: "My Venus is square my Moon" or "Venus is square Mars in my chart".

What are orbs?

Each aspect has an orb, which is a measure of how close the aspect is to exact. For example, if a square (normally 90°) is 93°, it has an orb of 3°. "Orb" can also refer to the maximum amount of variance from the exact angle that an astrologer allows for an aspect to have before they no longer consider it valid. For example, for a square, they may use a 10° orb, which means an angle that is anywhere between 80° and 100° would be considered a valid square.

Different schools of astrology have different opinions about orbs, and different software have different defaults that you can usually change. Major aspects like conjunctions, squares, and oppositions will have larger orbs, while minor aspects like sextiles or inconjuncts would have smaller orbs. Some people also allow larger orbs for the Sun and Moon.

How do you interpret symbols?

Once you know your placements and aspects, you can simply Google any of them like "Natal Mercury in Taurus" and get many descriptions. However, these descriptions can feel vague or generic, because they have to resonate with a lot of people.

Each description is based on synthesizing the symbolic meaning of the planet, sign, and/or house and describing different ways the various energies could combine. But that doesn’t mean they will combine in that exact way in your life. In other words, a generic interpretation may not describe your experience, as it cannot take into account the context of your life.

Astrology is more like dream interpretation than weather prediction

Astrology is a symbolic system, not a literal one. Each symbol represents a multitude of meanings, and combining them into something that makes sense is an art more than a science.

As an analogy, you can look up, “What does dreaming about a spider mean?”, and get generic interpretations, but to know how the spider symbolism relates to your life requires knowing about your life and putting the two together.

The magic of natal astrology happens in the space between you and the chart, when you apply the symbolic meanings of astrological symbols to understand yourself and how your life has unfolded.

Doing this level of interpretation for strangers takes a lot of study and practice to do well. However, I think everyone can benefit by learning about their own chart.

How do you learn astrology?

Learning astrology on a deeper level can be difficult, and everyone feels overwhelmed at first. That doesn’t mean you can’t learn it. It just means this is a 2000 year old system that has a huge amount of detail to it—and not everyone agrees on all the details.

I recommend starting with mastering the basics: the major Planets, the Signs, and the Houses. I also created a printable PDF of the houses. These are the bedrock of all astrological interpretation.

Putting together the meaning of a planet, sign, and house can be pretty daunting, but there are a few shortcuts that you should be aware of that make it easier.

Astrology has underlying patterns to it

Each sign has an element and mode. By memorizing these, you can quickly understand certain characteristics of a sign. For example, knowing Virgo is a mutable earth sign tells you that they are practical (earth), and adaptable (mutable). From that, you can understand why Virgo is so oriented toward problem-solving. When mutability meets water (in Pisces), the emotional and sensitive nature of water creates a dreamy and intuitive sign that blurs boundaries between reality and fantasy.

What are Planetary Rulers?

Each planet rules one or more signs. In the original Hellenistic astrological system, the rulership was as follows:

Modern planets have complicated this

Starting in the 1700s, we discovered many more objects in our solar system besides the visible planets that astrology was based on. These have been incorporated into modern astrology in various ways.

Most astrologers acknowledge a resonance between Uranus and Aquarius, Neptune and Pisces, and Pluto and Scorpio. There is disagreement about if they should be ruling those signs, because rulership is central to the original symmetry of the astrological system which did not involve these outer planets.

• Some astrologers only use traditional rulers as shown above.
• Some astrologers replace the traditional rulers for these three signs, using Uranus as the ruler of Aquarius, Neptune as the ruler of Pisces, and Pluto as the ruler of Scorpio.
• Some use them as "co-rulers" alongside the traditional rulers.

The argument for modern rulers

These new planets do show a striking similarity to these signs. (Although, it is also true that the meaning of these signs has started to drift toward the planetary meanings due to conflation.)

The argument against replacing traditional rulers with modern ones

The signs were originally seen as being "temples of the Gods". Venus being in a sign ruled by Mars said something about the relationship of Venus and Mars in your chart: Venus is in the domain of Mars and has to follow his rules but also has access to his resources. This affected whatever aspect (or not) that was made between them (this impact is called "reception") and created a "host and guest" dynamic. Removing traditional rulers also breaks planetary dignities (fall, detriment, exaltation, domicile), which are core to interpreting the condition of a planet in your chart.

My take

When I first started learning astrology, I used modern rulers as they are widespread. I assumed “new must be better” and thought there must be a good reason the older rulers were replaced. I also just didn’t understand how the system of rulers and dignity worked and it felt confusing.

When I started studying the original (Hellenistic) astrology, my feeling started to change. I understood why it was designed this way, and now I only use traditional rulers. Using modern rulers fundamentally breaks astrology as it was used for thousands of years, and it is simply not necessary. We can incorporate new astrological bodies without changing the rulership scheme of the original planets.

What is the “12-letter Alphabet”?

This refers to how modern astrology often associates each house with a sign and its ruler. This is a popular way of learning the house meanings, and is codified in some systems (like Evolutionary Astrology).

However—house meanings did not originally come from sign meanings

This is another part of modern astrology that doesn’t make as much sense when you realize how astrology developed. While this pattern is common nowadays, houses and signs did not originally have anything to do with each other.

• Signs meanings derived from the planets that ruled them, and the ratio of light and dark during the time of year the Sun was in that sign.
• The house meanings derived from the Whole-Sign aspect that house made to the first house, the position each house had relative to the closest angular house (1st, 4th, 7th, 10th), and which planet found its Joy there.

Which house system should I use?

Modern astrology usually uses Placidus, a quadrant-based house system. Hellenistic astrology uses Whole Sign Houses.

Quadrant-Based Houses

Quadrant house systems first divide the chart into 4 quadrants with the Ascendant, IC, Descendent, and Midheaven as the cusps of the 1st, 4th, 6th, and 10th houses. From there, different systems subdivide the remaining houses using different calculations.

Placidus is the most common modern house system, and is often the default in astrological software. Porphery is used by the Jeffrey Wolf Greene school of Evolutionary Astrology.

Whole Sign Houses

Hellenistic astrology used Whole Sign Houses, where each house corresponds to the entirety of a sign. This is very simple and straightforward, and many people prefer it after they have used it for awhile.

In Whole Sign Houses, the Ascendant is always in the first house, and therefore the Descendant is always in the 7th, but they do not form the cusps. The cusps are always at 0 degrees of each sign. The Midheaven can show up anywhere from the 8th to the 11th house, although the 9th and 10th are most common. The IC is opposite and can be in the 2nd-5th house.