Constellations and zodiac signs

The astrological signs of the zodiac are probably known to everyone today. Also, many surely know some of the 88 astronomical constellations. But what is the difference between a constellation and a zodiac sign? How are they created, and is it true that the zodiac signs, as they are assigned to everyone today, are actually wrong?

The origin of the constellations and signs of the zodiac

Constellations were already used in ancient times to orient people for place and time. Sailors could determine their exact position with the help of nautical systems and the constellations. Ancient peoples also used them to determine the seasons, create calendars, and plan sowing and harvesting.

Throughout history, they have been changed and renamed. Ultimately, many constellations, as described in the books of the Greco-Roman astronomer Ptolemy have prevailed. As a result, 48 constellations in Western culture today bear names derived from Greek mythology. Examples include the constellation of Princess Andromeda and her mother Cassiopeia.

In 1930, the International Astronomical Union (IAU) finally published a list of the 88 constellations in the night sky that are still valid today.

The history of the zodiac signs also begins in ancient times, when people still believed that the sun ran in a circle around the earth. Strictly speaking, it starts in Mesopotamia (Greek: "land between rivers"), an area in present-day Iraq and eastern Syria.

At that time, the region was characterized by particularly foreseeable weather conditions in the corresponding seasons. Rain and sunny days could be predicted very well here. Since people at that time determined the seasons and thus the weather by the positions of the stars, these were eventually said to have a connection to earthly events. Accordingly, horoscopes and divinations were developed based on the stars, which were even considered scientific until the 17th century.

Today, the role of the zodiac signs is significant for astrological interpretations, such as the character traits of a living being or the predictions in a horoscope.

The differences in size and position

The constellations were defined by dividing the night sky into areas containing conspicuous groups of stars. As a result, the constellations have different sizes, and the sun takes different amounts of time to pass through the constellations. For example, the sun takes about seven days to pass through the constellation Scorpius, which has an area of 497°, while it takes about 45 days to pass through the constellation Virgo, which has an area of 1,294°.

However, it seems only from the earth that the stars would belong together. Physically they have no connection. Often they are even very far away from each other. The effect by which the stars of a constellation seem to be close together is called projection effect.

The signs of the zodiac were created by dividing the ecliptic (the apparent path of the sun within a year) into 12 equal areas of 30° each. Accordingly, each of the 12 signs of the zodiac is exactly the same size, and the sun needs about 30 days, roughly one month, to pass through it.

The different definition of the constellations and the zodiac signs leads to the fact that constellations with the same name have completely different sizes. For example, the astronomical constellation Leo has an area of about 947°, but the astrological interpretation is based on a size of 30°.

Is it true that the zodiac signs we assign to everyone today are actually wrong?

To put it briefly, yes! About 86% of people actually have a different zodiac sign than they thought. Because since the zodiac signs were created thousands of years ago, the course of the sun has changed through the individual zodiac signs.

An explanation for this is the phenomenon of the axial precession of the earth, thus the wobbling movement. As a result, the zodiac signs of today are shifted by about a month. Today's Aries, for example, is actually a Pisces.