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The Disappearing Star and The Oldest Story Ever Told - Video học tiếng Anh
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The Disappearing Star and The Oldest Story Ever Told
The Disappearing Star and The Oldest Story Ever Told
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Phụ đề (143)
0:00
This video is sponsored by Squarespace.
0:03
Are you familiar with the group of stars known as the Pleiades?
0:07
Maybe you’ve heard them referred to as the Seven Sisters.
0:10
They’re bright and easy to spot, and as such, they’re well known to people all over the world.
0:15
Cultures from the ancient Greeks to the Aboriginal Australians tell stories about them.
0:20
Often a story of seven women.
0:22
Quick problem, though.
0:23
Have a quick peek at the star cluster.
0:26
In fact, if it’s a clear night where you are, pause the video and pop outside – I’ll wait.
0:32
How many stars do you see?
0:35
…Six, huh?
0:35
So how did so many people around the world make up a seventh?
0:39
There may be an answer to that question.
0:40
An answer that, with a little astrophysics,
0:43
could lead us to one of the oldest stories humans have ever told.
0:48
[♪ INTRO]
0:51
The story of the Pleiades as seven women is remarkably widespread around the world.
0:56
In Greek mythology, the seven stars of the Pleiades are the
1:00
seven daughters of the Titan Atlas, who was chased by the hunter Orion.
1:04
The god Zeus scooped up the seven sisters and placed them in the sky as stars,
1:09
out of the reach of the nefarious Orion.
1:11
Hindu epics call them seven wives of wise men,
1:15
some Aboriginal Australian cultures call them the seven water girls,
1:20
and legends from the Western Mono of North America call them seven
1:24
wives who were thrown out of their homes for eating too many onions.
1:29
Which is harsh, but… Onion breath.
1:31
I get it.
1:32
The stories aren’t ubiquitous.
1:34
In Japan, for example, the cluster is referred to as having six stars.
1:39
You can even see this in the logo of Japanese car
1:42
maker Subaru, which might as well be the unofficial state car here in Montana.
1:47
Still, with so many cultures with such similar stories about such a specific,
1:52
incorrect number of stars,
1:54
one starts to wonder: is this a coincidence, or some remarkable common thread throughout humanity?
2:00
Aboriginal Australians and ancient Greeks, for example, had not been in
2:04
contact since their ancestors left Africa a minimum of sixty thousand years ago.
2:10
Yet they tell similar stories.
2:12
Does that mean they brought the same story out of Africa with them?
2:15
Could the story of the seven sisters be tens of thousands of years old?
2:19
That would make it one of the oldest stories we know about.
2:22
To find out, let’s look at the stars themselves.
2:25
With modern astronomy, we now know the Pleiades are part of an open star cluster,
2:30
that is, a grouping of stars all born around the same time from the same huge dust cloud.
2:35
With a telescope, we can see that the Pleiades actually have over a thousand stars.
2:40
But our ancestors in ancient times didn’t have telescopes,
2:43
so let’s focus on what we can see with our own eyes.
2:46
Unless you’ve got spectacular eyesight, you can probably see six stars.
2:51
And even if you can see more than six, it’s probably way more than seven!
2:56
Some of the Pleiades myths actually acknowledge this mystery,
2:59
with an explanation of how the seventh sister went missing.
3:02
The Greeks, for example, said that one of the
3:05
divine sisters went into hiding for the shame of marrying a mortal man.
3:09
And there are more cultures than just the Greeks that acknowledge the missing seventh sister.
3:14
The Nez Perce, a nation of Indigenous people from the region around Idaho and Oregon,
3:18
told that one sister fell in love with a mortal man.
3:22
When he died and she was grieving, she felt her sisters were ashamed,
3:25
so she hid herself behind a veil, leaving only six sisters visible in the sky.
3:31
I mean, basically the same story!
3:33
This brings us back to the beginning: what the heck is going on with that missing seventh star?
3:38
Why do all these people across time and space on Earth agree there’s a seventh star,
3:43
where did it go, and when did it disappear?
3:46
One group of researchers thinks they may have figured it out.
3:50
According to their calculations, if you track the motions of the stars,
3:54
you can see that a seventh bright star may have actually been visible 100,000
3:59
years ago — we’ll come back to that time frame in a minute.
4:02
Stars move across the night sky in a couple of ways.
4:05
They appear to us to be moving because Earth is spinning around
4:09
its axis and moving in its orbit around the Sun.
4:12
At the same time, stars are actually moving through space.
4:16
Astronomers record how much stars really move on the night sky, not including the motion
4:21
that we only see because of the spinny little vantage point on our homeworld.
4:25
This is known as a star’s proper motion, usually measured in tiny fractions of a degree per year.
4:31
The researchers thinking about the Pleiades used these measured proper motions to predict
4:36
where the stars of the Pleiades may have been hundreds of thousands of years ago.
4:41
With this method, the scientists found that two of the Pleiades — Atlas and Pleione — might have
4:47
been far enough apart that our eyes could see them as two separate stars back in the day.
4:52
They claim that now we only see six because they’re too close together
4:55
for our eyes to tell them apart without help from binoculars or a telescope.
5:00
One small problem.
5:02
This finding was presented in a chapter in a book, where you’re not required to
5:06
show your work in as much detail as you would be in a paper in a journal.
5:11
So we had to check it ourselves.
5:13
Yes, really.
5:14
We asked an astrophysicist to check this and she did the math.
5:18
Here it is.
5:19
What this shows is that yes, indeed, Atlas and Pleione used to be farther apart.
5:25
Maybe far enough to see them as two separate objects with the naked eye.
5:29
It’s an amazing idea, but there are a few issues that we’ll get to after this quick break.
5:36
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6:17
So. We have the claim from these authors that our ancestors would have been
6:22
able to see seven stars around 100,000 years ago.
6:26
That supports the idea that stories about the Pleiades have been around
6:29
since ancient humans were all bopping around together in Africa.
6:34
It’s a really cool idea, but we have to note a couple of possible
6:39
snags in the narrative these researchers present.
6:42
The stars in the Pleiades are quite young,
6:44
and young stars surrounded by dust can sometimes be variable in their brightness.
6:49
The “Atlas and Pleione on the move” idea doesn’t account for the fact that maybe
6:54
one of these could have been way brighter or fainter in the past.
6:58
And when we talk about hundred thousand year timescales there’s a lot more to
7:02
consider with how stars move that we didn’t really talk about.
7:05
For example, Earth’s orbit is even more complicated than the
7:10
spin around our axis and our orbit around the Sun.
7:13
The circularity of Earth’s orbit and the tilt and
7:16
wobble of Earth’s axis are subject to change over tens of thousands of years.
7:21
All of these things could contribute to Atlas and Pleione appearing in
7:25
slightly different places than our simple calculation from proper motion predicts.
7:30
Plus, even a tiny margin of error could matter a lot here — as far
7:34
as humans leaving Africa compared to the time scales of the universe.
7:39
And, quick note from when we were fact checking this script.
7:42
The authors of the piece say that the ancestors of the Aboriginal Australians left Africa
7:47
a hundred thousand years ago, but we aren’t completely sure where they got that number.
7:52
The scholarly consensus seems to be that although some humans left Africa much earlier,
7:57
the bulk of the migration was only around 60,000 years ago.
8:01
It still works if you imagine that the stars were visible a hundred thousand years ago and
8:06
people were still telling that story by the time the migration happened,
8:09
but still, just pointing that out.
8:11
The independent scholar Jon White also notes that some versions of the stories of the seven
8:16
sisters are actually more different from each other than they seem at first glance.
8:21
Like, the Aboriginal Australian stories focus a lot more on water and ritual than the Greek myth.
8:27
Plus, there are a whole bunch of other Pleiades stories we haven’t even mentioned!
8:31
Maōri mythology called them Matariki, and they represented the eyes of a god lost in battle.
8:38
Hawaiian mo’olelo tales say that a greedy nobleman hoarded food and stored it in the sky,
8:44
out of reach, until a little mouse came along and gnawed the ropes of
8:48
the net until the food fell back down to the people on the islands.
8:52
Those are only two examples, and there are plenty more – and I’d say
8:56
they’re both pretty different from seven sisters!
8:59
So, after considering all this, did this story of the Pleiades travel out of Africa with us?
9:05
Did people notice a star disappearing over time, and adjust the story to it?
9:10
It’s really hard to be sure, but this is a neat and at least somewhat scientifically backed idea.
9:15
Plus, it’s pretty incredible to think about humans telling stories about stars for so
9:20
many thousands and thousands of years that a star was able to move through the sky and disappear.
9:26
What an amazing way to preserve the history of the sky itself – and connect us all at the same time.
9:34
[♪ OUTRO]
