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So, what are zombie stars?

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This is kind of a nickname

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that we're giving the white dwarf
in this particular system.

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So you can think of a white dwarf
as a star

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that's
kind of reached the end of its life.

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So you can think about that
as it's like a zombie.

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And then what happens is it

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grabs
material from the secondary star nearby,

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and that goes on the surface
of the white dwarf.

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And then we have the explosion
within that material.

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And that's the nova outburst.

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You can think about the zombie being
reinvigorated and being much more active.

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And then after a while,
when it doesn't get to eat anything,

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it goes a lot quiet again.

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And then with this particular system,
in eight years, it

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will eat some more material
and become re-energized again.

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So when we think about,

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Taco Bell and the White Dwarf,
we give it the nickname of a zombie,

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So why are
we interested in this particular system?

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Well,
this is, only 3000 light years away,

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and the outburst
is going to be particularly bright.

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It's going to be comparative to Polaris,
which is, about about second magnitude.

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And so we're gonna be able to view it
very well, and we're gonna be able

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to do that now with a bunch of different, 
telescopes and facilities.

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So we haven't really, 
used before on this object.

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So originally, scientists thought that
this star was going to explode

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by September.

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Now, this is what we call a recurrent
nova system.

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So what I mean by
that is that it has to have an outburst.

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So that's when the material is ejected
from the surface,

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the white dwarf from that explosion.

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And then what would happen
is after all that matter was, you know,

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after that's been flung out,
it will grab more material

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from the secondary star

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and then build up again, and then I'll
have another eruption, another outburst,

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and that we'll see in the sky.

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Now, for this object.

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This happens every 80 years or so.

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So I believe the first record of this
happening was in 1217.

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And then the last outburst
that we saw here on earth was in 1946.

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And we kind of have seen as astronomers

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that this seems to have happened
every 80 years or so.

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And previously before the outburst,
we tended to see this kind of behavior

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where it's decreased in brightness
very slowly.

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And then once we started to see
that slight decrease in brightness.

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But a year or so later,
we saw the outburst, the big eruption.

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Now this decrease in brightness
started happening.

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Can't remember the top of my head,
but it seemed to indicate that

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the next eruption should happen,
before September of this year.

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Now we've already gone past September
and it hasn't happened yet.

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But that's because this is kind
of unpredictable science.

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You know, it might be
it will happen before the end of the year.

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It might actually happen next year.

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It's all really
an estimate. And it keeps us,

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second guessing what we see.

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So we'll see some trend,
but it might not happen.

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And if it doesn't happen by next year,
that also gives us some other

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interesting information
about the system as well.

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So either way, we'll find out
something really interesting

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about what's going on in the system,
whether we see an outburst

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in the next few months
or maybe later on next year.

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So this,

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Nova event happens about every 80 years.

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And it is only 3000 light years away from
us in the Northern Crown constellation.

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And because it's so close

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and because it gets so bright,
we can learn a lot from this system.

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But also most importantly is since 1946,
we actually have new facilities,

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which will observe x rays and gamma rays,

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and we can coordinate all of our
observations together on this object.

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So we're going to really understand
the physics

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of what's happening in the explosion.

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Get a better understanding of the dynamics
between the two stars, and learn

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about the composition
of the stars themselves.

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So how can you

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see this, new star when it does go nova?

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And what can you do to prepare?

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So essentially, this, Nova, this bright,
this new star is going to happen

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in the Northern Crown constellation or
Corona Borealis, and that's near Hercules.

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And the way in
which we'll be able to view it.

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Well, if you have, a dark night sky,
you'll see a,

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brighter star in that constellation,
and it's going to be

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comparatively bright to Polaris,
which is a second magnitude star.

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Additionally,
what you can do if you don't have dark Sky

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is you can also, you know, use various
apps on your phone like Sky view

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or to make sure you know what that,
where that region is

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and also when you found it,
know what it should look like.

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And then when it goes into the outburst,
you'll see that slightly brighter

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star in that region.

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You're not going to see a huge explosion
in space, obviously, but you will see

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a slight brightening of
a star in that constellation.

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So what am I most excited about?

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This event?

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This is something that I'm never going
to get to go see.

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And once it's, really
is every 80 years or so.

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And I think for this event,
because we're going to have so

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many facilities observing it,
we're going to learn so much more

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about what's happening
and the physics in the system.

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And I like to think of novae
as mini laboratories

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for other more, energetic events.

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So now we really help us to understand
the physics that are going on

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in these binary systems
and what we call accretion.

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So the way in which we grab material
from one star and put it onto another.

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They really help us
understand that process,

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and they can help us to understand it
on a bigger scale as well.

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So I'm really excited about
the new physics that we're going to learn

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with all these amazing
facilities that we now have.

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So will our star.

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Our sun ends up like this
system will have the same fate.

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The answer is no.

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All star is a, a star in isolation.

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And it doesn't have
that secondary companion

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from which you can steal material.

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So it could have a Nova event.

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So eventually
Asan is going to become a white dwarf,

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and it will spend the rest of his time
just cooling down.

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So the last time that this nova went into

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eruption was in 1946,
and we didn't some have

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some of the facilities
that we now have today with NASA.

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Essentially we can use facilities
like Fermi and Sby and James

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Webb and Hubble to do a multi wavelength,
campaign on this object.

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We can observe it in the visible.

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So what you view with your eyes,

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but we can observe it with gamma ray
detectors and x ray detectors.

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And this is really important to gain
a full understanding of the system itself.

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So the composition of things, the,
the accretion processes that's dragging

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material from one star on to another
and the explosion mechanism itself.

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so what is the difference between
a nova and a supernova?

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Well, a nova system.

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And that could happen multiple times

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because the system isn't destroyed
once the explosion happens.

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It's just an explosion on the surface
of the white dwarf in a supernova system.

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Well, the the system is destroyed.

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That white dwarf is destroyed
in the explosion.

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And you cannot have a recurrence
happen again.

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A supernova event is much more energetic.

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And a one time thing

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So why are

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nova important and what role do they play
in solar system development?

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Well, Nova are actually
quite frequent events in our galaxy.

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And another galaxies.

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And by observing them
we can get a lot of insight

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into other, other, energetic events.

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They also produce a lot of lithium, which
is really important for, our galaxy.

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And, you know, having what we call
heavier elements.

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So novae are frequent, bright.

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And we can also, observe them
from the ground in some cases,

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which makes them even more exciting.

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so what are scientists doing

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to observe the system
and getting prepared for its explosion?

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Well, there are several telescopes,
I believe, which are still observing.

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It's to check
when it will go into outburst.

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But typically we get a lot of information
from, the amateur astronomer communities

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who tend to focus on a region
in the night sky and then send out alerts

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the broader community to let us know
that this event has been happening.

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That's how, actually, a lot of novae
have been detected in the past.

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And so when one of those alerts
are sent out to the community,

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everybody else will jump on board and
start observing with their own facilities

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and with the space
based facilities as well.