The Birth Chart: Understanding the graph, how it works and why it’s an indispensable tool to understand yourself

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When I’ve started studying Astrology, I perfectly remember the confusion and the frustration that I felt the very first time I saw a Natal Chart.

Doctor Angiolucci, who was introducing me to Astrology, showed me the drawing of a Birth Chart and then he started: – “Do you see? Jupiter is in Leo and in the 8th House so it means that…”– and – “Do you see? The Sun is above the horizon so it means this…”– and – “Do you see? Mercury and Mars are in Square so it means that…” –

My face was like: “Ah, of course! Oh yes! Naturally!”, but inside my mind was like: – “Horizon?! Where do you see the horizon?? Strange symbols?? Numbers?? Lines?? Letters?? Colors?? Tables?? What a hell is this circle??!”– .

It seemed to me like watching an ancient egyptian papyrus.

So I stopped Angiolucci: – “Excuse me, I cannot understand what this drawing is, what’s that graphic? Why is it a circle? How it works? Why do I need that stuff to study Astrology?”–

Angiolucci answered: – “It is a scheme of the sky at the very moment of your birth, it’s obvious!” –

Me: – “Sorry Doc, IT ISN’T!”–

Now, don’t misunderstand me, Doctor Angiolucci was very good on Astrology, the point is that many experts very often talk to you like you are already a professional astrologer. They forgot how hard was at the beginning, and everything is completely new for a total beginner.

There are many people who are very interested to Astrology, but they never saw a Natal Chart, they don’t know how to obtain one, and above all, they don’t know how it works and why it is useful, and even when they obtain it, they feel completely frustrated and lost.

It’s easy for them feel despondent and then they abandon.

So, now we will see how to obtain a good graphic of your Natal Chart, and we will analyze every single piece of it, to understand how it works, its basic psychological meanings, why it is helpful to make the right psychological interpretations and why it’s a powerful tool for your personal growth.  

Well, every Art needs its proper instruments, and so it is for Astrological Art.

The essential instrument to correctly interpret your stars, is a graphic that represents the entire sky at the very moment of your birth; that graphic is called Natal Chart or Birth Chart.

It is a very important instrument, because your Birth Chart is like a detailed map of your psyche, so studying it deeply means understanding yourself better: every side of your personality, why you behave the way you behave, the way you love, the way you communicate, your attitudes, your virtues and your weak points.

It will help you to completely accept yourself and rise your confidence and your level of awareness.

But there is another good new: After the acceptance you can start to develop and improve yourself for the better, because your stars are not your “destiny”; Astrology doesn’t tell you about your “doom” as unfortunately it is the common view of it; the real Astrology is a practical psychological instrument to heal ourself and the others; it’s a tool to expand your vision of life.

Astrology is a roadmap to a better version of yourself.

So you can understand that is really fundamental having a good graphic of your Birth Chart to study it, very precise and very detailed.

In ancient times, the only way to obtain that graphic was to do it all by yourself, drawing circles and lines with a pencil, calculating every positions of the planets and stars your own through ephemerides, using compasses and protractor to mark every geometrical ratio (well, I think that on an advanced level it is important to use those tools, but it is not necessary now); but fortunately we live in the age of technology and, above all, we have the power of the internet.

You can find many Birth Chart calculator on the web, I tried a lot of them through the years, but in my opinion there is just one good Birth Chart Calculator on-line: Astro Dienst.

Here is the link:

That site is a point of reference for the most part of professional astrologers in the world, and it has the best Birth Chart Calculator on the web, full of details, precise, customizable, very user friendly, and it’s free; you can create 5 Natal Charts as a guest user or more than forty as a register user, again for free.

Choice is yours, anyway at this point it is enough to use it as a guest user, so let’s proceed.

At the home page of, move the cursor on “Free Horoscopes” button up on your left, then a window will appear.

At the section “Drawings & Calculation” click on “Natal Chart, Ascendant”, then proceed as a guest user and you will arrive at the data entry page.

Here are the indispensable data you need:

  • Your First Name
  • Your birth date (day, month, year)
  • Your gender
  • Your birth hour (hr, mins)
  • The Country where you are born
  • The Town where you are born

Just a note: The birth hour is essential for having a complete Natal Chart, but you don’t need to be absolutely precise.

For example, if you are not sure if you are born at 8:00 pm or 8:10 pm, that’s not a problem, 10 minutes are a good range of tolerance, the positions of planets and stars cannot change very much in 10 minutes. But if you are not sure between 8:00 pm and 8:20 pm, then yes, more than 15 minutes could be too much and the positions of planets, especially the fastest (Moon, Mercury, etc.), could change a lot.

So be sure to insert a birth hour as precise as you can.

It’s the same for the birth town. If you cannot find your exact birth town into the database, it is not a big problem, choose the closest town to your birth place, it will be enough.

Anyway, even if you don’t know your birth hour or your birth town, don’t worry, you can have your Birth Chart, but it will be incomplete, it will be without the Astrological Houses.

It is not a big trouble now, because you can see the positions of all your Planets in any case, so you will be able to make the basic and fundamental interpretations of them and then of the main parts of your own psyche.

Well, insert all the data, and after checked that all data is correct, push the “continue” button and so you obtain the graphic of your Natal Chart.

You could be a little bit disorientated seeing it, especially if you are a beginner, that is normal.

The Chart is full of strange symbols, signs, numbers, lines, shapes, graphics, etc, but you don’t have to feel discouraged, you need just a little bit of patience and step by step we will analyze the structure of the graphic Chart in every part that composes it, then very soon you will start to understand how it works and how it is a complete map of your psyche.

Let’s proceed to the explanations.

Understanding the graphic structure

The first thing to learn, it’s knowing every part that composing the Chart: Drawings, lines, sectors, tables, etc.

So here is an image to explain it:

And now we analyze those pieces more deeply:


no. 1 – Your data

There are all data inserted to create the Natal Chart, you can check if everything is right, and you can also have some interesting information like the coordinates of the birth town or the conversions of the birth time to “Universal Time” and “Sidereal Time”, this last one especially is important to calculate the real position of Planets and Astrological Houses, but it is not important now, because the site calculates everything automatically. Those data could be useful for a professional astrologer on an very advanced level of study.

Instead, there is another little information that might be very useful to know just near the birth date: Which day of the week you are born.

Everyone of the seven days that compose the week is consecrated to one of the Seven Traditional Planets.

It is pretty clear if you think about the names of the days, especially on latin derivative languages, but there are some tracks of this truth even in english (like monday, saturday and sunday).

The Sequence of the Days of the Week, is based on the “Chaldean Sequence”, a very ancient astrosophical sequence arrived to us through the babylonians and ancient egyptians (more than 3000 year ago). It is also the base for the Decans, but they are for an advanced level of study, it is not important now.

Knowing in which day of the week you are born is an information that could suggests something about your psyche, because the Planet of the day you are born will be a little bit “amplified” in your Natal Chart.

For example, if you are born on Thursday, the influence of Jupiter, in other words the part of your psyche that it represents (wisdom, expansion, etc.), will be a little bit amplified.

If you like numbers, we can say at least 15-20% more.

Here are the days of the week and their correspondences:


– Monday – lat. Lunae-die – The Day of the Moon

– Tuesday – lat. Mars-die – The Day of Mars

– Wednesday – lat. Mercurius-die – The Day of Mercury

– Thursday – lat. Iuppiter-die – The Day of Jupiter

– Friday – lat. Venus-die – The Day of Venus

– Saturday – lat. Saturnus-die – The Day of Saturn

– Sunday – lat. Solis-die – The Day of the Sun


Our current Gregorian Calendar is pretty accurate to calculate the succession of the days of the week, so we can use it as a secure parameter and in my experience on interpreting Birth Charts, the day of the week should  be considered.


no. 2 – Type of Chart

Here you can check the type of the chart, in this case a Natal Chart, but there are other types of charts, like the Sinastry Chart for example.

The Method says to you the style of the drawing, because there are many customizable styles for registered users, and it also says to you the calculation system used to calculate the positions of the Astrological Houses, in this case it’s “Placidus”.

There are many methods to calculate the Houses, actually someone very experimental, but there are just two main methods: Koch Method and Placidus Method. 

The last one, Placidus (from the name of the monk who developed it), became a sort of standard method through the centuries, because it considers the inclination of Earth’s axis, the Celestial Equator, the true zenith, and the complex trigonometric ratio between all the points, so it is the most accurate method to define the relations between the birth place and the sky.

The most part of professional astrologers use it, me too, and I can say even through experience that it’s reliable.

In fact, even use it as a default method, and I think this is perfect.

At the end, here you can also quickly check your Zodiac Sign (Sun Sign – “your Self”) and your Ascendant (Rising Sign –“your way to express your Self”).


no. 3 – Positions/Dignities Table

Here you can find the exact position of every Planet or Astrological Object with their very degrees on the Ecliptic (the apparent path of the Sun). It’ s very important to know that, especially to truly define the Aspects between Planets or Points, or even to understand better a Planet that is on a Cusp between Signs, because the circle drawing cannot help us in that situation.

For example, if on the drawing I see Mars in the Cusp between Sagittarius and Capricorn, I am not capable to define where actually it is through the drawing, so I can check the Positions Table and knowing that Mars is at 0 Cap 22’ 51’’ or in other words, in Capricorn at 0° 22’ 51”, so even if for less than 23’ , Mars is in Capricorn and this level of detail is really important to know in an interpretation of a Natal Chart because Mars in Capricorn is on Exaltation, and then the influence of Sagittarius on it will be very low.


no. 4 – Elements/Qualities Table

In this table you can quickly find in which Element and in which Quality, Planets and other Points are.

That is very useful to have a general vision of the dominant Element and dominant Quality of your Natal Chart.

Every Zodiac Sign belongs to an Element and possesses a Quality, so every Planet or Astrological Point acquires the characteristics of the Element and the Quality of the Zodiac Sign where they are placed.

On the left side of the table there are the Four Elements: Fire – Air – Earth – Water, they are even marked with colors to help having a good vision of the dominance: Red for Fire, Yellow for Air, Green for Earth and Blue for Water, and so every Zodiac Sign Symbol of the circle.

That’s important because the dominant Element could tell us about your dominant psychological temperament, in fact, to each one of the Four Elements corresponds one of the four psychological temperaments, but even many other psychological key concepts.

Here are some basic correspondences:

Fire –> Choleric temperament  –>   Intuition

Water   –> Phlegmatic temperament –>  Emotions

Air –> Sanguine temperament –>   Mind

Earth –> Melancholic temperament –> Senses

So, many Planets, and especially Sun of course, in the same Element suggests a dominance of that Element and then of that temperament.

On the top of the table you can find the Three Qualities: Cardinal – Fixed – Mutable, every Sign possesses one of those Qualities. A Quality is the main characteristic and tendency of a Zodiac Sign.

Here are some basic psychological associations:

Cardinal Wants to be a point of reference  – Balanced

FixedWants to remain the same – Rigid

MutableWants to change – Adaptable

As for the Elements, many Planets in the same Quality suggest a dominance of that Quality on the personality.


no. 5 – Aspects Table

On that table you can find any main Geometrical Aspects between every Planet or Astrological Point.

The Aspects are represented by conventional symbols, the blue and the green symbols are generally harmonic Aspects, red symbols are generally dynamic Aspects. I will talk better about them on some future article.

This table is really useful, because, at the begin, you are not able to define which kind of Aspect involves two Planets through the drawing only, so you can check here, for example, if a blue line that connect Mars and Sun stay for a Trine or a Sextile.


Well, now it is time for analyzing every part that compose the true core of the Chart, that visual instrument that permit you to have the better and complete vision of the big picture of your Sky, and then of your psyche: the drawing.


no. 6 – The Zodiac Circle or Wheel

The zodiac circle represents the Ecliptic.

The ecliptic is the apparent path of the Sun on the sky, created by Earth’s movement in his own orbit. We can consider the Ecliptic as the core of the entire astrological system, because every planet or point of the system has importance when it is related with it.

The ecliptic, so the Sun, passes through 12 constellations in one year, those special constellations which represent the 12 archetypes we call Zodiac Signs.

It’ s the same for all the other Planets, which follow the ecliptic always.

The Sun transits for almost 30 days (1 month) on each one of those constellations, so every zodiac sign occupies 30 degrees of the ecliptic (1 degree = almost 1 day), and you can see it easily on that circle drawing: we have the 12 symbols of the zodiac Signs and every symbol has divided in 3 sectors of 10 degrees, so 30 degrees totally, to make it more readable.


no. 7 – Planets and other Astrological Objects

All those symbols inside the zodiac circle represent the Planets or other Astrological Objects and Points, and all of them are positioned on a circle’s degree, so with the help of tables it is very simple to understand in which zodiac sign they are placed to easily understand their nature.

In Astrology we define “Planets” the 7 ancient traditional planets, Sun, Moon, Mercury, Venus, Mars, Jupiter and Saturn, plus the 3 trans-saturnian planets, Uranus, Neptune and Pluto.

Please note that the word “planet” is used with symbolic meaning (from the ancient greek “planetos” = “wanderer”), the different astronomical classification between Mars – planet, Moon – Satellite, or Sun – Star, has no importance in Astrology.

Astrological Objects or Points, are not planets, and sometimes they are not physical objects, but special points in the sky obtained through mathematical and geometric calculation.

An example of Astrological Object is Chiron, because it is not a planet but a comet, and an example of Astrological Point could be the Lunar Nodes or even the Houses, because there are no physical objects on those points.

As you can see, every planets, points or objects is represented by a symbol on the circle. It is fundamental knowing the symbols, because symbols and symbolisms are the true language of Astrological Art.

It could be a little bit frustrating at the beginning, but I guarantee to you that with the help of the tables on this free guide, with planet’s names and their symbols, after a few times you will start to memorize them and you will be able to recognize them at the first look.

By side every symbol you can find numbers, they are the degrees of the Ecliptic where the planet or object is placed.


no. 8 – Astrological Houses or Sectors

The inner circle is divided in 12 sectors and every sector has a progressive number. Those sectors are the 12 Astrological Houses that represent a specific area of your psyche that projects itself on a specific area of your life.

There are 4 House Points that are the core of the Cardinal Houses and represent the 4 cardinal points of your sky. They form two axes, one horizontal (AC-DC) and the other one vertical (MC-IC).

They are:

First House –> Ascendant (AC) –> the East –> the rising sign

Seventh House –> Descendant (DC) –> the West –> the falling sign

Tenth House –> Medio Coeli (MC) –> the South –> the highest point of the ecliptic

Fourth House –> Imum Coeli (IC) –> the North –> the lowest point of the ecliptic

Very often, the vertical axis will be diagonal, it’s normal because, as I said before, the Placidus system to calculate Houses considers many astronomical factors related to the birth place, as the inclination of the Earth’s axis or the elliptic orbit of our own Planet.


no. 9 – Aspects

At the centre of the circle there are many colored lines that connect some planets or point. Each one of those lines represents an Aspect, a geometrical relation that connects 2 or more Planets which are involved in some kind of interaction (harmonic, not harmonic or neutral).

On blue and green lines are harmonic aspects generally; red and black lines are dynamic aspects generally.

It could be useful for a beginner take a look at those lines to have a general vision of the main aspects, but on an advanced level of study of your natal chart, it is more useful leave those lines and start studying every planet and his aspects one by one, using more deep parameters and classifications to interpret them.


Well, now that you know every piece of the Chart, you can start to analyze it to find every psychological correspondence that will help you to know yourself better.

Studying how the circular drawing works and which astronomical concepts are behind it, it’s fundamental to fully understand what you are doing and, after that, beginning to understand the psychological meanings behind every part or piece of the graph.

So, as I said before, the circular graphic represents you and the entire sky at the very moment of your birth, it is like a 360° picture of your own birth sky.

At the center of the circle, you can see a point signed by a little cross. That point represents your birth place, or, to be very precise, that point represents you at the very moment of your birth.

In fact, many people think that Astrology is geocentric, but that is not completely exact: Astrology is anthropocentric.

Human Being, not the Earth, is the center of the system.

The AC–DC axis represents the horizon. The AC point is the East and the DC point is the West, that’s why the AC point is the Sunrise point and the DC point is the Sunset point.

The Zodiac Wheel apparent motion is clockwise as the Sun, because the Earth rotation is counterclockwise, so the AC point is the point of the rising zodiac sign, the Ascendant, and then the DC point is the point of the falling zodiac sign, the Descendant.

Every other Planets follows the ecliptic’s path, so even every Planet follows the same apparent motion of the Sun through the Zodiac Wheel.

The MC–IC axis represents the Zenith–Nadir axis; the Zenith (MC) is the highest point of the ecliptic and the south point, and the Nadir (IC) it is the lowest and the north point.

So you can easily understand that the half circle above the horizon (AC-DC axis) represents the day-part of the sky and the half circle below the horizon represents the night-part of the sky.

Here is a scheme of it:


Please note that I used a flat section of the Earth on the imagine above just to make that imagine much easy to understand. Of course, our Gaia (Earth) is a sphere like every other Planets.

Of course, that imagine shows a daytime birth as example. It’s the opposite for the nighttime birth (Nocturnal Hemicycle above the horizon, Diurnal Hemicycle below the horizon).

As we can see, the AC-DC axis divides the circle in 2 half-circles called:

The Southern Hemicycle – The Medio Coeli side, and The Northern Hemicycle – The Imum Coeli side.

And it’s the same for the MC-IC axis that divides the circle in other 2 half-circle called: The Eastern Hemicycle – The Ascendant side and The Western Hemicycle – The Descendant side.

Those informations are important because they give you some basics informations about your psyche; each one of the hemicycles represents a basic psychological tendency and could define a basic psychological type.

There are 4 psychological types: Abstract, Concrete, Active and Passive.

Each one of those types are represented by a hemicycle:

Southern Hemicycle:  Abstract.

Northern Hemicycle:  Concrete.

Eastern Hemicycle:   Active.

Western Hemicycle:  Passive.

Here is the graphic:


Many Planets, and especially Luminaries (Sun and Moon), on the same hemicycle suggests your main psychological tendency.

Here are the meanings of the 4 psychological tendencies:


  • Abstract type – Tends to be an idealist and dreamer. He might live without certainties.
  • Concrete type – Tends to be practical and pragmatic. He couldn’t live without certainties.
  • Active type – He thinks that he can influence the external context. He thinks that he can forge his own life.
  • Passive type – He tends to be influenced by the external context. He thinks that the external world forges his life.


Furthermore, the 4 hemicycles merge together and divide the sky circle even into 4 Quadrants, and they create the mixed types: Abstract–active, Abstract–passive, Concrete–active, Concrete–passive.

You can see all that on the imagine above.

Od course, all you need to do is to merge the 2 psychological meanings of the Quadrant to understand it.

Those psychological concepts will be more clear when you will understand the Zodiac Signs’s symbolism and especially the meanings of the Astrological Houses more deeply, because those Quadrants are connected with the Houses System.

You can find some fundamental informations about Astrological Houses in this article.

Well, now you know how the graph works, and you can understand why it is extremely useful to make the right psychological interpretations about the stars.

It makes you capable to have the whole vision of every single piece and how they merge together and interact each other.

Yes, it could be a little bit hard at the beginning looking at every piece at the same time and try to understand how everything is connected, but it’s normal: it is a job that you need to do level-by-level.

This is just the start point.


Now that you know how the drawing works, you’re ready to learn how your Stars tell you everything about your own personality. Get my free guide – Know Your Planets, Know Yourself • Astrology Fundamentals – and understand who you are.

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