As a teen, I loved reading my horoscope in gossip magazines. But still my friends and I knew it was nonsense. To us, it was a fun pastime for bored teenagers. So I was surprised when my hairdresser recently asked me my star sign. When I shared my opinions on astrology and horoscopes, she simply replied, “Typical Taurus.”
Astrology is currently experiencing a remarkable renaissance-Especially on social media, where posts about “Geminis”, “Leos” and “Virgos Rising” are everywhere. The trend may partly reflect how deeply people want to identify personality types and, in the process, gain some insight into an uncertain future. And perhaps surprisingly, many astrology posts come from people who consider themselves scientifically inclined.
how can that be? Today modern science and astrology stand in complete opposition to each other. There’s no evidence that your sign actually affects your daily life. Yet the origin of the horoscope is not entirely unscientific. It’s actually a story that begins with careful observation of the universe and the creation of a calendar system in the Middle East thousands of years ago.
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What exactly are the zodiac signs?
The zodiac signs, considered by many to be the foundation of modern astrology, are based on 12 constellations: Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius, Capricorn, Aquarius, and Pisces. These are by no means the only constellations visible in the night sky. In 1922 the International Astronomical Union (IAU) officially recognized 88 constellations, including constellations associated with the zodiac and other famous examples such as the Big Dipper.
Thousands of years before the IAU was founded, people in ancient Mesopotamia were contemplating the constellations. He gave special importance to those located in the apparent path of the Sun, also called the ecliptic.
Due to Mesopotamia’s geographical location, weather patterns here have historically been highly consistent. There is a rainy season and a dry season. Wind direction can also be predicted based on the time of year. And because certain constellations appeared in the night sky at different times of the year, people might believe there was a connection between the stars and these seasons.
This idea isn’t so great: after all, scientists today believe that the Sun and Moon actually influence earthly phenomena like weather and tides. But distant stars, as we’ll discuss later, are a different story.
At the end of the fifth century BC, Babylonian astronomers divided the ecliptic into 12 equal segments of 30 degrees each, corresponding to the 30 days of the 12 months of their calendar. In doing so, he developed the first known astronomical coordinate system. He assigned each section a constellation located in the night sky along the ecliptic at that time of year.
This is how astrology began. Zodiac signs and the superstitions associated with them spread from Mesopotamia to Greece and Rome and eventually became part of European tradition.
Times are changing—and so are the stars
Looking back, it doesn’t seem so far-fetched that people in ancient times or the Middle Ages believed that the constellations influenced us. I don’t understand how this belief continues to this day.
We now know a lot about astronomy, physics and celestial mechanics. For example, scientists have long understood that constellations are composed of objects that are sometimes far away and have no connection to each other except that they appear close together from our vantage point on Earth.
Furthermore, their distance from Earth is so great that they – unlike the Moon or the Sun – cannot really affect us or our planet. Stars light years away are giant fusion reactors that do not shape our personalities or life events.
If you are reading this article, I assume you do not believe in astrology. But if you find yourself talking to someone who is interested in horoscopes, here are three scientifically based points you can pick up:
Actually there are 13 zodiac signs. If you look at the constellations along the ecliptic, you will find not 12 but 13 of them during a year. Ophiuchus, the serpent bearer, was forgotten. Or rather, perhaps it was deliberately omitted from the list because it did not fit into the Babylonians’ 12-month system.
Not every zodiac sign corresponds to a month. While traveling along the ecliptic, the Sun passes through the boundaries of the zodiac signs for different periods of time. For example, the Sun passes through the boundaries of the Scorpius constellation for only six to seven days, while it takes 44 to 45 days to pass through the boundaries of the much larger Virgo constellation.
Zodiac signs keep changing with time. More precisely, the Earth’s axis of rotation makes a wobbly motion like a spinning top, a phenomenon known as precession. This movement changes which constellations are visible on the ecliptic at what time of year. Whereas in Babylonian time, the constellation Aries appeared on the ecliptic starting on March 21, today the constellation Pisces appears instead on that day.
Are you still determined to find your star sign?
A scientifically correct zodiac system Is present. In this, every constellation is situated in the ecliptic in modern times.
Amanda Montanez; Source: “Zodiac Signs and Constellations,” Jeremy B. By Tatum, in Journal of the Royal Society of CanadaVol. 103, number 3; June 2010 (data)
This is quite different from the system that is still used for astrology today. But don’t worry, scientific American Not going to print horoscopes based on the revised zodiac sign – except, perhaps, as a joke.
This article originally appeared in spectrum der wissenschaft And was reproduced with permission. It was translated from the original German version with the help of artificial intelligence and reviewed by our editors.
