Explanation of the zodiac in astrology

The zodiac is determined by the position of the Sun in the sky compared to 12 constellations and is closely related to astrology.

Zodiac, or 12 signs are listed in the horoscope, associated with the movement of the Earth in the sky. Since the Earth revolves around the Sun on a flat surface, we will see the Sun appear and move in front of different constellations for a year, according to Earth Sky.

Just as the Moon appears at a slightly different position in the sky over each night, the Sun's position compared to distant background stars gradually moves eastward from day to day. For example, if this month the Sun is in the constellation Gemini position, the next month it will be in the position of the Cancer constellation.

Specific dates are listed in the Western horoscope to identify when the Sun appeared in a zodiac. For example, from March 21 to April 19 is Aries. Currently, the zodiac when you are born does not necessarily coincide with the constellation name that the Sun is passing.

12 zodiac signs associated with the movement of the Earth in the sky.(Photo: Wordpress).

To understand why the constellations are no longer suitable for the corresponding zodiac, we need to know more about how the Earth moves . The Earth rotates and its North pole does not always point to the same direction. Like the spinning, Earth also swayed, making the North pole move into a circle in the Heavenly Bridge. This shaking is quite slow with a 26,000-year cycle, making the Earth not actually complete an orbit within a year. After about 2,000 years, the Sun will be in a completely different constellation position at the same time.

On the summer solstice in June 2,000 years ago, the Sun was almost in the middle of the constellation Gemini and Cancer. But in the summer solstice in 2016, the Sun is in the position between the constellation Gemini and Taurus. In 4609, the Sun will leave the constellation Taurus to go to the constellation Aries in the solstice.

The zodiac coincides with the corresponding constellation that the Sun goes through determined 2,000 years ago. But in the middle of the 21st century, the slow shaking of the Earth's rotating axis caused the low-point, winter solstice and spring equinox, the feces to be moved about 30 degrees to the west compared to the constellations. Currently, zodiac signs and constellations are about a month apart. In about 2,000 years, they will be about two months apart.

Zodiac constellations do not have the same size and shape. Most of them appear in ancient Babylonian texts and were introduced by Ptolemy, a Greek astronomer who lived in the 2nd century.

In 1930, the International Astronomical Society demarcated modern constellations with all 13 constellations located along the Sun's path. The constellation not listed in the western horoscope is the Ophiuchus (Ophiuchus) between the constellation Sagittarius and the Scorpion.