From what it is, to why it's so bizarre, join as we explore Mira, the strangest star in
the universe.
In the universe above, there are many, MANY kinds of stars.
there are ones that shine brighter than any other out there, and there are some that are
so dim that you won't be able to see them unless you're very close to them.
Some stars become black holes, and some become Neutron Stars that are arguably SCARIER than
black holes.
Regardless though, there's no doubt that stars make up a large part of our universe, which
is why when it comes to the star known as Mira, it's a strange one.
Why is it so strange compared to all the other stars in the sky and the universe beyond?
Because it is technically a falling star.
Which I'm sure gives you all sorts of imagery, but it's not exactly what you think, and yet,
it is kind of what you would expect.
Let's start with the basics, shall we?
Mira as it is known is a star that is 700 times larger than the diameter of our own
sun.
Which makes it quite sizeable when you consider that our sun is 865,370 miles in diameter.
That's not a small star, which makes Mira very massive in comparison.
As for when we found this very unusual star, that would be 134 BC via the astronomer known
as Hipparchus.
This was backed up by various other Chinese astronomers in their own journals, and obviously
today we can confirm that it is a star that is in our sky.
But that's only the beginning of the story.
Because when it comes to its weirdness, a very random encounter led to that bit of information
being discovered.
David Fabricius was the one who made this unique discovery.
But he wasn't looking for the star, rather, he was looking at Mercury.
On August 13th, 1596, he was observing Mercury, and trying to gather the distance between
it and a star that he had noticed in the sky that was in a nearby constellation.
The reason for this desire was quite simple, he had never noticed this star before, and
when he tried to look for it in the maps of the stars that had been made by 1596, there
was no trace of it.
Now, on some level this is to be expected, after all, the earliest days of astronomy
weren't known for their accuracy.
Rather, they were known for wild speculation, incorrect analysis, and often times not realizing
that something was right there when they thought it was something else.
Uranus for example was first thought to not be a planet, but something else entirely.
And as such, it didn't get to planet status until a little while after its discovery.
Anyway, getting back to Mira, the reason that Fabricius was so fascinated by it was that
it appeared to be a rather interesting bright star with a magnitude of 3.
But, as he kept watching it, by the end of August (a mere two weeks or so after first
discovery), he noticed that the intensity of the star had actually grown to magnitude
2.
Which made it not just a very bright star, but one that was the brightest in the constellation
it was in.
Which shouldn't have been possible based on what we know on stars and their movements
and abilities.
Right?
And it only got weirder as the months went on, because in September, it didn't get bigger
and brighter, instead, it shrank and got dimmer.
Then, by October, the entire star had vanished from the sky.
Perplexed, Fabricius decided to not try and find the star as he felt it wasn't worth the
effort for what was "clearly" not a new star.
But then, 13 years later, on February 5th, 1609...the star came back, and Fabricius was
there to see it once again.
And he wasn't the only one to notice, because a few years prior, Jonathan Bayer had noticed
the star in the sky and put it in his famous Star Atlas.
But because he wasn't with Fabricius in the decade prior, he didn't understand the importance
of the star or what it could mean for astronomy as a whole.
Between these two scientists, the world would soon know about Mira, and for many decades
to come scientists and astronomers would look up at it and try to figure out what was going
on with it.
Especially since it was now a magnitude 4 star.
This perplexing star in the sky got so much attention that it was eventually named Mira
because it's the Latin word for "Amazing".
Which is an apt description for the star given all that it can do, and the mysterious nature
that it brought to the skies of Earth.
Before we continue to dive into what Mira is, and why it's so strange, be sure to like
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If you're still not fully grasping what makes Mira so special, allow me to be a little more
basic in its description.
During the vast majority of the year, the star Mira is so dim that you can't see it
without a very good microscope and knowing where to look.
Ok?
But, as Fabricius and others noted, at certain times of the year, not only does it shine
brighter, it becomes the brightest star in the Cetus constellation.
Which isn't something you'd expect from a star that isn't transforming into the next
phase of its life.
And, just as weirdly, it'll go from being the brightest thing around to being dim once
more.
This cycle is one that continues on and off with both reliability, and yet, irregularity.
Scientists can't always determine when it'll go bright or dim, but they can count on it
to follow its cycle.
Thus, it is what we know as a Variable Star.
That "variable" in this case is its brightness if you couldn't tell.
Over the course of 332 days give or take, the brightness of the star will go from its
most dim, to 3 and a half times brighter.
For a star, that's an incredible change in regards to its brightness.
In context, at its dimmest, it's known to be Magnitude 10, which means it's a star that
is basically invisible in terms of brightness.
But then, at its peak, it reaches Magnitude 2, which made it the brightest of the constellation
that it was in.
Now usually, you'd expect some kind of pattern to this dimming and shining, but outside of
it going up and down in terms of brightness, there isn't any pattern.
In short, the star is unstable in its brightness, and that's why scientists can't simply determine
where this brightness comes from at points or how long it's going to stay alight or be
invisible to the exact date and time.
And at some points, the brightness of the star doesn't go fully bright or fully dark.
During one cycle, it went from Magnitude 10 to Magnitude 2, the full ends of the scale.
But in another, it only went from Magnitude 9 to Magnitude 5 before dimming once again.
There is no serious pattern to this, nor rhyme or reason as to why it goes up and down inconsistently.
However, there are those who believe they know a reason why we are able to perceive
that brightness change.
You see, when a star changes in brightness, or pulsates, it doesn't just change in intensity
of its shine, but also, in its temperature.
Think of it like a flashlight.
If you hold it far away from your hand, you're not going to feel the heat from its light,
but if you get closer to it, and thus the light is more intense (in this context) your
hand will feel the effects of the heat.
It's the same principle here.
And as we all know, heat and temperature affect everything around you.
In the case of Mira, it affects the atmosphere, and it's believed that when it's at its maximum
magnitude, the atmosphere around the star becomes a lot clearer and thinner.
And as a result, the intensity of Mira's star is conveyed.
Or at least, that's one theory that some believe is happening with the star.
But believe it or not, there is still much more to discuss with the star.
Because in 1919, a new discovery was found.
Mainly in that there isn't just one star called Mira, there is a satellite star called Mira
B that circles that main star, and unlike Mira, it's a White Dwarf star.
Why does this matter?
Because this particular White Dwarf star is FEEDING off of Mira, and that means it's having
a direct affect on the star.
But, there's a twist in the tale here.
You see, you'd think that this feeding would be noticed, or that the star would've been
caught a lot earlier by Fabricius or Bayer or someone else, right?
Except, it wasn't, and for good reason.
The reason it hadn't be discovered until 1919 was because Mira B only orbits its parent
star once every 400 years.
So that means that since Fabricius "found" the star all the way back in 1596, that it
hasn't had a full rotation around Mira.
What's more, the distance between Mira and Mira B is much greater than the distance between
Earth and our Sun.
The distance between the Earth and the sun is 93 million miles.
which has now been classified as 1AU or "astronomical unit".
The distance between Mira and Mira B is 70 Au.
Yeah, it's 70 times LONGER than the distance between the Earth and the sun.
However, despite the distance, Mira B does take after its "parent" in many aspects.
Including the fact that it too sees rises and falls in the intensity of its magnitude
or shine.
However, unlike Mira, we know why this is the case.
In short, because the White Dwarf is sucking mass away from the star, it has an accretion
disk around it that it has to interact with.
The inconsistent levels of mass that it gets allows the star to shift in magnitude.
However, also unlike Mira, the intensity of said shifts is much small.
At its dimmest, the star gets to about Magnitude 12, while at its brightest it only goes to
about 9.5 Which no doubt is a reason that scientists didn't notice it earlier.
Because Mira shines MUCH brighter than Mira B by several intensities, so of course astronomers
would notice that one first.
And would you believe it?
There is STILL more to talk about with this star.
In 2003, a very special satellite known as the Galex was set to observe Mira, and when
it did, it noticed something very unexpected.
Mainly, there is a trail of mass being left behind by the star.
Which because of its orbit and movement throughout the galaxy it's in, makes it appear like a
comets tail.
To be clear, this is NOT the mass that is being absorbed by Mira B. It's something else
entirely.
Would you like to know the length of that "tail"?
That would be 13 light years.
If you need a little context as to how long that is, I'll help you out.
If you were to draw a line from our sun to the closest star that is next to it, you'd
reach Alpha Centauri in about 4.2 light years.
And it would take humanity with our current technology about 165,000 years to reach that
star.
So now, times that by 3, and you can see that this "tail" is a very long piece of mass.
One of the other reasons that this is unexpected is that it deals in direct contrast to how
the other stars behave.
Most stars follow the galactic rotation of the system it's in.
Which usually means a spiral pattern.
But for Mira, it doesn't do that.
Instead, it shoots through space at 130 kilometers per second.
Because of that speed and the intensity of which it's shooting through space, the "tail"
of gasses isn't one to follow the gravity of the galaxy, but rather, be shot back right
behind the star.
Oh, and the mass it's dispersing?
If you take 10 years of it, you get about the mass of the Earth.
And it's believed that to make this particular length of a tail it took about 30,000 years.
Which no doubt makes many wonder why it started to disperse the mass around then.
So truly Mira is something special, and yet, it is part of a club.
For while it is one star that is unique in many aspects, it's a Variable Star, and there
have been tens of thousands of Variable Stars found all over the universe.
And because we know what to look for in regards to them now, we can search for them and find
them wherever we look.
And we have, more are found every year.
None of them are quite like Mira, but that's ok, because stars like this one need to be
alone to be truly special.
And if there was a true lesson to be learned from this, it would be thus, the stars that
fill up our skies and universe are still a mystery to us in many ways.
We're still learning how they form, how they transform, the effects that they have on planets,
and apparently, even how they shine.
It's easy to think of stars as simple "balls of light", but the truth is far more complex
and wondrous.
Which is why finding ones like Mira truly test our knowledge of them, and create a burning
desire to see what really makes them tick.
Thanks for watching everyone!
What did you think of this look at the star known as Mira, and why it is indeed the strangest
star in the universe today?
Can you believe that such a star exists with such properties?
Do you think that other stars like this exist out there somewhere?
Let me know in the comments below, be sure to subscribe, and I'll see you next time on
the channel!