The Pleiades: Humanity’s Oldest Story?

This time of year in the Northern Hemisphere is a wonderful time for stargazing, if you can deal with the temperatures. Colder temperatures mean the air is stiller, allowing for crystal clear nights, and several of the brightest stars in Earth’s sky are visible in the cold months. Also visible in the sky these days is an intriguing little cluster of stars which I consider to be the first of the winter sky to rise in the late autumn—the Pleiades, or the Seven Sisters.

What is this wee cluster? Where did it come from and what will become of it? And what might it have to do with humanity’s oldest surviving stories? Let’s meet the Sisters. 

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Where to Look

Finding the Pleiades in the sky is relatively simple, if it’s clear out and you don’t have a sky completely blasted out by light pollution. There are a couple of ways to find them. One is to just look for them. They appear as a tiny cluster of faint stars which I’ve heard described as looking like a Little Little Little Dipper. This is different from the sky all around them, which means that often the eye is drawn to them without any other aids. They’re visible rising in the east just at sunset and are up all night.

That said, the Pleiades do have a very handy pointer, though at the moment it’s not rising until later in the evening: Orion’s Belt. This line of stars is well-known because it’s easy to spot. Nowhere else in the sky will you find such a neat line of three bright stars, which means again that the eye tends to be drawn to it. If you’re not sure if you’ve spotted the Belt or not, look above and below it. The Belt will have two bright stars above it (Orion’s shoulders), and two below it (his knees). 

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Once you’ve spotted the Belt, you can use it to find the Pleiades. Follow the direction it points upward. Keep following it through the V-shape of stars that marks the head of Taurus the Bull (anchored at one end by a brighter star, Aldebaran) and it will take you right to the cluster of the Pleiades.

Looking at the cluster with your eyes, you will not be able to see seven stars, despite the name “Seven Sisters”. We’ll get to the why of this later, but for now it’s best to accept that you’ll probably only see six stars if you have good eyes and a dark sky. In fact, what you’ll see will look suspiciously like the Subaru logo, except it’s not actually suspicious at all because the car company is named for the Japanese name for this cluster and the company uses the cluster as its logo.

Of course, however many stars you can see with your eyes, the cluster is suspected to contain over a thousand stars. What we see with our eyes are just a few of the brightest. Slap a telescope or pair of binoculars on this baby and you’ll see what I mean.

An Open Cluster

So that’s how to find it. Now…what is it? A star cluster, obviously, but what the heck does that mean? It is specifically known as an open cluster, which means that all the stars in it were formed at roughly the same time from the same nebula. 

Stars tend to get born out of giant clouds of gas and dust in space called starbirth or star-forming nebulae. Basically the gases of the nebula collapse down into clumps which become the stars, meaning the stars are eating up the nebula by being formed. If a powerful telescope looks at the Pleiades, there are a few wisps of this parent nebula still visible, but mostly it’s gone.

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This all happened to the stars of the Pleiades relatively recently—they’re around 100 million years old. To a human that’s forever. To a star like the Sun, with a lifespan of about 10 billion years, all told, that’s the blink of an eye. To stars like those in the Pleiades? Well, for the bright ones we can easily see it’s probably most of their lifetimes. Stars that bright just don’t live very long, at least compared to stars like the Sun. They’re not likely to live long enough to see the cluster disperse. 

Most stars are born into clusters like this one. Our Sun was probably part of one once, in its earliest days, surrounded by its sibling stars that had all been born from the same parent nebula. But that was five billion years ago, and all those stars have scattered over the eons, the ones still alive anyway. And the same thing will happen to the Pleiades in time—models estimate another 250 million years or so before this cluster is thoroughly dispersed. By that point, the big bright stars we easily see now will have long since run out of fuel and died.

Storytelling

Quick: what do the Tuareg Berber people of north Africa, the Kiowa people of the North American Great Plains, the Wirangu people of southern Australia, the Ban Raji people of western Nepal, and the ancient Greeks of, well, Greece, have in common?

Bilaterally symmetric anatomy! And also a legend about this cluster of stars being seven young women. There are several other cultural groups whose legends refer to this being seven people or seven young men, but the idea of it being specifically seven young women is one that appears over and over again in different peoples from around the globe that had absolutely no contact with each other in antiquity.

That’s interesting to anthropologists. When specific mythologies seem to be shared across very widely distributed groups, one possible explanation is that the myth behind it all is a very old one. For instance the group of stars that we call Taurus the Bull, so very close to the Pleiades, has a very long history of being identified as a bull by many different ancient cultures in the vicinities of North Africa, Europe, and Western Asia. Not so widespread as the Kiowa and Wirangu, but still a hike back in the day.

We also happen to know that the idea of Taurus as a bull is a very old idea. This is thanks to the fact that some enterprising Stone Age individual painted a beautiful picture of a bull with the stars of Taurus’s head inside of it and the Pleiades on top of it on a cave wall in France 17,000 years ago. So here’s a case where we know the story of this group of stars being a bull is a very old one, and its age appears to mean it spread with migrating peoples to many areas of the ancient world that adopted and adapted the legend of the sky bull as their own. 

A Tale as Old as Time?

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So now let’s go back to the Pleiades and the idea of them being seven young women, often but not always sisters. There’s two very interesting things to take from this: the young women and the number seven.

The fact that so many widely separated cultures have viewed the Pleiades as young women on its own doesn’t necessarily imply an old origin. Seeing stars as people wasn’t weird. It’s interesting that so many folks saw the Pleiades as young women, but it doesn’t firmly suggest anything on its own.

What does is that all of these cultures see them as seven young women. Seven. While folks with incredible eyesight have been known to be able to spot numerous stars in the Pleiades, the average human can maybe spot six. And yet, so many cultures, including many of those who identify this cluster as young men instead of young women, specifically mention seven. Several legends even include stories explaining why one appears to be missing. 

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This widespread idea of seven stars being easily visible in the cluster, alongside the common identification as young women, has implications. That suggests age. There is no reason why people living in America, Africa, and Australia should all see the Pleiades as a cluster of seven unless that idea is old.

How old are we talking? Well, there was a time when seven stars would have been easily visible. The stars in the Pleiades are moving around, and two of the brightest have moved so close together that the human eye can’t really separate them anymore, but way back when they would have been distinguishable as two. 

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The last time the average human would have been able to easily see seven stars in the cluster would have been about 100,000 years ago. The exact date of human migration out of the continent of Africa is unknown, but a recent DNA study puts it sometime between 50,000-60,000 years ago.

It is possible—possible, mind you—that the reason that indigenous groups from Asia, America, Europe, and Australia all tell the tale of seven young women in the sky is because that tale began before humans entered any of those places. It may come from our earliest years as a species, when all Homo sapiens were still in Africa, with a far greater chance of sharing stories and beliefs. Those tales could then be carried through generations of migrants making their way to the farthest corners of the Earth. Along the way they would mutate, combine, split, and be forgotten. Except, maybe, for one idea which managed to carry through—seven young women in the sky.

Ancient Connections

There’s no way (that I’m aware of) to really prove or disprove this theory. And even if we could, it’s not likely to have any sort of effect on anyone’s day-to-day life. But it’s an idea that sticks with you and it’s one that I love—that there, in the sky, is a story that connects us back literally to the earliest of our human ancestors.

So the next late autumn or winter evening that you look up and spot the Pleiades, take a moment first and foremost to appreciate their beauty. Maybe spend a second admiring the incredible intricacies of the stellar lifecycle on display in the cluster. And, perhaps, if you’d like to, take a moment to imagine someone a hundred thousand years ago doing the exact same thing you’re doing: looking up and admiring the Seven Sisters.