Understanding birth chart lines is a vital part of mastering astrological readings. This includes aspects, but also houses, degrees, and other crucial angles that can’t be ignored when interpreting a natal chart.
Push your knowledge of the craft further by learning about each type of line on your birth chart, the role it plays, and the meaning it holds for you.
1. Birth Chart House Lines
House lines, also referred to as house cusps, divide the chart into 12 pie-shaped pieces.
There are 12 houses in a birth chart and each represents a specific area of your life.
I think of the houses as the verbs of astrology because they describe things that you do.
The 2nd House, for instance, describes how you relate to, spend, make, or behave with your money and resources.
The houses are numbered in order, counter-clockwise, from 1 – 12 with the 1st House always found on the left side of your chart. It represents the eastern horizon at the exact moment of your birth.
House lines in your birth chart may or may not be equally spaced so the houses could be different sizes, as seen in the example chart below.
This will be dependent on which house system you are using, your birth city’s distance from the equator, and what time of year you were born in.
You can learn much more about houses in our in-depth article for beginners found here.
Before you go any further, we made you a Birth Chart Lines worksheet that goes along with this article, FREE when you sign up for our newsletter below!
Even though all house cusps are vitally important birth chart lines, there are a few that hold extra significance. These are referred to as angular houses.
The Ascendant (AC)
One very important birth chart line is the cusp, or boundary, of the 1st House which is also called the Ascendant in astrology and is considered one of the angular houses.
Along with your Sun and Moon, your Ascendant is considered part of the “Big 3” in astrology because it contributes so heavily toward how you experience life.
Some astrologers call this special angle the “mask you wear” because it describes how you interact with the world.
Dive deeper into the role your Ascendant plays in your chart and life in our article all about it found here.
The Descendant (DC)
Directly across from your Ascendant in your natal chart you will find your 7th House cusp and another significant angular house, your Descendant.
You can think of this angle as “who you are not” as it represents traits, desires, and motivations that you may not recognize in yourself.
Because you may feel as though this line describes characteristics that aren’t strong in your personality, these may be the exact things that you are naturally attracted to in other people as they may “balance you out.”
Some astrologers even go as far as to describe your Descendant as your soul mate.
What can you learn from the Descendant line in your chart? Find out in our in-depth article here.
The Nadir (Imum Coeli, IC)
Toward the bottom of your chart is another vital natal chart line and that is the Nadir, which is also the cusp of your 4th House. This line is also called your Imum Coeli.
This crucial, angular house in your birth chart represents the most private version of yourself.
It encompasses the ingrained thoughts you have about yourself, both good and bad, that you have probably held since childhood.
I have seen the Nadir described as your roots, your inner center, and the place where you hold the greatest dreams and worst nightmares for yourselves.
The sign and condition of your IC give hints as to what family baggage helped to form your sense of self and who you truly believe yourself to be.
The Midheaven (Medium Coeli, MC)
The cusp of the 10th House is also known as your Midheaven or Medium Coeli. The line for this angular house is found at the top of your chart and lies opposite of your Nadir.
The Nadir is the most personal point in your birth chart, but the Midheaven is your most public point.
This line represents your public image and reputation. This is different than the “mask” of the Ascendant that you show to the people you interact with day in and day out and describes your more general social standing.
Your Midheaven also indicates the kind of work that may bring you the most satisfaction. This line points toward the greatest goals you hold for yourself and what kind of career you may feel the most ambitious about.
2. Aspect Lines in Your Birth Chart
One type of birth chart line that you need to understand is aspect lines.
Aspects describe specific angles that are made between two different points on your natal chart. The size of the angle defines which type of aspect is made.
The chart above was made in the astrology software I use, TimePassages. All of the lines crisscrossing in the middle of the circle are aspects between two points.
Think of aspects as relationships between two points, such as two planets. Depending on the aspect, or size of the angle, these relationships can be friendly or stormy, although every type of aspect has its drawbacks and its potential for personal growth.
The blue lines in your birth chart symbolize soft aspects which are characterized as harmonious types of relationships.
Two main types of soft aspects are trines and sextiles and they depict relationships where there is rapport and support.
Soft aspects seem agreeable and the placements involved, such as two planets, may cooperate well, with one supporting and encouraging the goal and desires of the other.
Which soft aspects exist in your chart and how can they change the dynamics between your planets? Learn much more in our guide to soft aspects here.
Hard aspects are considered the most difficult types of aspects and these are often shown as red lines in your birth chart.
Two types of hard aspects are called squares and oppositions and they represent relationships that seem anywhere from tense to nearly impossible.
Of course, hard aspects aren’t necessarily “bad,” Where there is friction there is the spark to grow, and where there is agreement there can also be stagnation.
It just depends on how you work with what you have!
We also have an article dedicated to hard aspects which you can find by clicking here.
3. Degree Lines in a Natal Chart
One last vital birth chart line to understand is the degree line.
In Western Astrology, astrological charts are circular. And, as you learned in geometry class, circles are measured in degrees.
Birth charts are no different.
Just like every other circle, your birth chart can be divided into 360°.
These degrees are used in astrology to describe exact placements of anything from the planets to the nodes to the house lines themselves.
When you look at your birth chart, the degree lines are marked on the outer circle.
You can pinpoint anything on your birth chart by referencing the sign, and degree of that sign, it sits in.
Understanding how to read degree lines in your birth chart is crucial. Dive deeper in degrees in astrology in our article that teaches you everything you need to know, found here!
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