Disclaimer: If you base a significant portion of your everyday decisions on information about your zodiac sign, stop reading, now. This investigation might cause severe repercussions in your world. We don’t want to be responsible for your emotional distress.
Okay, those of you who are still with us, let’s do a quick experiment.
Get a star tracking program like Stellarium, which is free to download, and look up the exact date of your birth, down to the year (the time of day is not important). Now, find the sun. What constellation is behind it? Is the constellation your zodiac sign? I thought not. For some of you, it will be, but for the rest of you, what you just learned by way of star charts from the date of your birth, is that you were born under the zodiac sign preceding the one you’ve grown up claiming as your own.
But why is this happening to me, you might well ask. Well, here’s the hard science that’s available to us now.
No such system of observation, hypothesis, and testing existed at the time of the invention of the Horoscope. There is something called axial precession. If you paid attention in school, you know the rotation of our planet happens along a line called the axis. But while earth spins along, the actual axis it rotates along shifts over time, in much the same way that a top starts to wobble as it spins. This effect changes the relative positions of the stars in our sky (known to astronomers as the celestial sphere). The rotation of our axis happens at a glacial pace, completing one rotation every 26,000 years. If you want to see this effect in progress, you can actually use Stellarium to see into the future. If you select the north star and jump a few thousand years ahead, you’ll notice that it begins to move out of the northern part of the sky, away from its fixed point.
Because the zodiac signs were determined thousands of years ago, axial precession has caused the dates during which the sun moves through the various constellations to change. So yeah, you’ve been deceived. It’s disconcerting, right? Even if you don’t put any stock in astrology, it’s no fun finding out that this common part of your identity, silly as it may seem, is a fabrication.
But that’s where it gets complicated. Even though the star signs are a bit of a ruse, there may actually be some truth to the idea that people born during certain times of the year have shared traits. Over the years, studies have found connections between birth month and everything from susceptibility to disease to future career path. Some of these connections are considered spurious, coincidental. But others actually seem to have some causality. One of them is height. A 1998 study by University of Vienna anthropologist Gerhard Weber found that people born during the month of April tend to be the tallest in the general population, whereas people born in October tend to be the shortest. This could have to do with exposure to sunlight in an infant’s prenatal and early postnatal life.
Given that information, the general traits of your star sign may be closer to the truth than you would think, even though the reasoning behind them is flawed.
Of course, horoscopes also rely heavily on what is known as the “Barnum Effect,” which demonstrates that people tend to believe the vague descriptions horoscopes offer because of their own positive bias. This effect was discovered by psychologist Bertram Forer, who gave his students a personality test as an experiment. When the students finished, he gave them their results, explaining that each description was unique and based on their specific answers. In reality, he gave each student the same description, letter for letter. The students were asked to rate the accuracy of the description on a scale of 0 (very poor) to 5 (excellent). On average, his students rated their results at 4.26.
Whether horoscopes derive their accuracy from the world we are born into or from our own willingness to believe them, modern science assures that they don’t have much to do with the alignment of the stars at the time of our births. That doesn’t mean that horoscopes can’t be enjoyable, or that you don’t really possess the traits associated with your sign, but if you’re getting ready to make a major life choice based on something you saw on the back of a pack of Bazooka bubble gum, you might want to give it some deeper thought.
- Does knowing your ‘real’ star sign change your opinion of horoscopes?
- If your ‘real’ star sign is different than before, do you identify more with the new one or the previous one?
- Are you, or do you know people who are, deeply emotionally invested in their star signs and daily horoscopes?