The natal chart or cosmogram is the basis of any horoscope. This is a graphic representation of the ecliptic that shows the position of the planets at the time of a person's birth. Errors made when constructing a natal chart can give a version of the horoscope, which will be the absolute opposite of its correct interpretation. How to build a natal chart?

## It is necessary

- • drawing accessories, paper, calculator;
- • tables: ephemeris, houses of Placis, coordinates of cities and time corrections, logarithms, corrections for sidereal time from solar

## Instructions

### Step 1

In order to build a natal chart, we find out where and when a person was born (exact coordinates and time). The meaning of the cusps (i.e. the tops of the houses of the horoscope) is found in accordance with the local sidereal time (MST) of birth.

The algorithm for calculating the MLV is as follows:

• You need to find out the time zone to which the place of birth belongs. This can be done using tables of city coordinates. Next, we find out, from the time correction tables, the difference between standard time and Greenwich, as well as whether there was an adjustment for daylight saving time. The hourly difference from GMT can be positive or negative. It is necessary to subtract this difference from the time of birth, taking into account the sign before the amendment. We also take into account the correction for summer time, for the east longitude we subtract 1 hour, for the west longitude we add. We get GMT (Greenwich Mean Time).

• Since GMT is the same for the whole belt, you need to find it for the place of birth. The longitude of the place of birth is taken and multiplied by 4 minutes. If the received number exceeds 60 minutes, then we translate it into hours, minutes and seconds. Now you need to adjust the time of birth of a person by the amount of this correction. For eastern longitude, the correction is added, and for western longitude, it is subtracted. We get the real time of the place of birth (RWM).

• Sidereal time in Greenwich, at midnight or noon (depending on the originator), is taken from the second column "Ephemeris" called "Sid Time". Further, the local sidereal time (LST) is calculated, the formula of which has the form: PBM + Sid Time + correction "from solar time to sidereal".

• A correction to correct the difference between sidereal time and solar time can be taken from a special table. The value we are looking for will be located at the intersection of the column (GMT hours) and the line (GMT minutes). The correction is given in the form of minutes and seconds separated by a space. First, we bring it to the correct form (for example, 00 h 02 min 12 sec.), And then we substitute it into the above formula for calculating the MZV. If the local sidereal time (MST) is more than 24 hours, then you need to subtract 24.

### Step 2

After the time data has been received, you can proceed directly to the construction of the natal chart. We draw a circle on paper using a compass or a round protractor, and divide it into 12 sectors containing 30 degrees each. This will be the zodiac circle. Traditionally, the signs of the zodiac are indicated counterclockwise, starting with Aries.

Now you need to break the natal chart into houses. There are also 12 of them in the horoscope, but they do not always coincide with the signs of the zodiac. The cusps are found using the Placis House Tables. This handbook contains tables in the upper left corner of which the MLV is indicated, and the Lat column indicates the geographic latitudes of the place of birth. We find a table with the time and latitude data we need. At the intersection of the Lat row and the columns with the Asc points (Ascendant) and the vertices of the houses (11, 12, 2, 3), we find the data we need. We find the zenith point (MC) in the center of the topmost row of the table, next to the local sidereal time (MVZ). The Ascendant is the top of the first house. MC is the top of the 10th house. From the Placis table, six cusps can be recognized, and the rest of the vertices are easy to find out, because their houses will begin in the same degree, but in the opposite sign of the zodiac. The natal chart will be divided into twelve astrological houses.

### Step 3

The construction of the natal chart will be completed when there is a cosmogram. The positions of the planets are taken from the ephemeris table, so they need to be adjusted according to the time of birth. Logarithms and logarithmic tables are used here.

The algorithm for calculating the position of the planets is as follows:

• Find the difference between the initial positions of each planet on the day following the birthday and on the birthday;

• Next, we calculate the logarithm of the difference found above, and the logarithm of the time of birth according to Greenwich Mean Time.

• Then you need to add these two logarithms and calculate the logarithm of the result of this sum, that is, convert the sum of the logarithms to degrees.

• If we add the initial position of the planet at the time of birth and the degrees of the sum of the logarithms obtained in the previous paragraph, then we get the position of the planet at the moment of birth of a person.

• Similarly to the above method, the position of each planet is calculated and then marked on the natal chart.