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If you spend any time studying space, you’re bound to find some strange stuff;
that’s one of the best parts about astronomy.
But every now and then, even the most experienced scientists
find something that makes them scratch their heads.
Like Przybylski’s Star.
We’ve been studying it since the 1960s,
but we still can’t seem to figure out what the thing is made of.
And according to one study, that might be because it contains elements or isotopes
scientists have never seen before.
Move over, Tabby’s Star, because this might be the weirdest star in the universe.
Przybylski’s Star is about 370 light-years away,
and it’s named after the Polish astronomer who first studied it.
Przybylski published his first paper about the object in 1961,
based on spectroscopy observations.
This is a common method that links the type of light a star emits
to the elements it contains, among other things.
And right away, he knew the observations of this star weren’t normal.
For one, based on its spectrum, the star seemed to have barely any iron in it, which was weird.
Most stars survive by fusing lighter elements into heavier ones,
and iron is one of the most common results.
On the other hand, this star also seemed to be chock full of lanthanides,
even heavier elements like holmium and europium,
which normally aren’t as abundant in stars.
At the time, Przybylski suggested this star must be pretty far along in its lifespan
to have produced so many heavy elements.
But today, we know the story is a little more complicated than that. Isn’t it always?
Thanks to lots of scientists and telescope hours,
we now know that Przybylski’s Star is actually part of a special class called
Ap stars, or A-type peculiar stars.
Regular A-type stars are usually hot and have no magnetic fields.
But Ap stars have cool surfaces, strong magnetic fields, and really long rotation periods.
For some reason, these stars also tend to have lots of lanthanides, but not much iron.
So in that respect, Przybylski’s Star isn’t as odd as we first thought.
But that doesn’t mean it’s normal, either.
According to a few papers, there’s evidence that this star
also contains atoms that have no business being there at all.
Specifically, ones like promethium and plutonium.
These elements and their isotopes, or versions with a different number of neutrons,
have relatively short half-lives.
This is the time it takes for half of the atoms in a radioactive substance
to decay into something else.
Promethium, for example, has a half-life of less than 20 years.
And plutonium has a half-life of some 24,000 years at most,
which is still barely any time at all for a star.
That means that, unless they’re new additions or are being replenished somehow,
they should have all completely decayed by the time humans and telescopes showed up.
So far, there are a few possible explanations for this.
Some astronomers have suggested that these atoms could have come from a recent supernova,
or from ongoing reactions catalyzed by a nearby neutron star.
But the evidence for these ideas isn’t that strong.
You also can’t have an astronomy mystery without some alien hypotheses.
But, uh, if you have any peer-reviewed papers about that, you can let us know.
Still, there’s one other possible explanation that doesn’t involve First Contact.
And if it’s true, it would change the textbooks, and not just the astronomy ones.
In 2017, in the journal Physical Review A, three researchers suggested that
Przybylski’s Star might actually contain super heavy elements or isotopes
we haven’t even discovered yet.
And, over time, these super heavy atoms could decay into the short-lived isotopes we’ve observed.
Specifically, they proposed that the atoms could be versions of three elements:
flerovium, unbihexium, or unbinilium.
We’ve made really tiny quantities of flerovium in the lab before,
like, around 100 atoms total, but we’ve never seen it in nature.
And although we think unbihexium and unbinilium should exist based on what we know about chemistry,
we haven’t observed them yet.
So if this hypothesis is true, it would mean that studying Przybylski’s Star
would let us see these atoms in the wild, or at all, for the first time!
There’s even a chance that the isotopes in the star would be part of the
island of stability, a hypothetical group of heavy, extra stable elements
that scientists have been trying to track down.
That would make this star not only important for astronomy,
but for chemistry and physics on Earth, too.
Now, it is worth mentioning that the team didn’t have any new explanation for how
those heavy atoms would’ve gotten there.
And there’s still a chance we misread the data, and that Przybylski’s Star
doesn’t really contain short-lived isotopes.
After all, the spectrum for this star, like the one Przybylski first used to study it,
is difficult to read.
Normally, spectra have a few fairly clear-cut lines that scientists can link to different elements.
But for this star, those lines are kind of all over the place.
So there’s an ongoing debate about what’s going on, because something weird is
definitely happening to produce that messy spectrum.
One helpful next step would be to take more measurements and hope they’re clearer.
But there’s a lot of other stuff to study, too, so most people aren’t actively looking into it.
In the meantime, researchers will keep trying to solve this mystery with what they have.
And maybe one day, they’ll get to name some new elements because of it.
Thanks for watching this episode of SciShow Space!
If you’d like to learn more about how stars have transformed the universe,
you can watch our episode about the very first stars.
Because without their influence, you wouldn’t be here.
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