>> Stephanie Marcus:
Good morning,
and welcome to the final
talk of this season.
We're already looking
forward, of course, to 2019
and another wonderful
set of talks.
And maybe another
visit from Alex.
I'm Stephanie Marcus from
the Science, Technology,
and Business Division.
And our speaker has
been here three times.
That's more than anybody
in the series, ever.
And this will be th
14th year next year.
And three times in three years.
And he is our Mr. Sunshine.
He's the, [laughter].
Yes, oh no!
He spilled his water.
[Laughter]
>> Alex Young: Didn't
hit any ca-- .
Didn't hit any cables,
so we're good, okay.
Alright.
>> Stephanie Marcus: I
gotta get out of here.
[Laughter] So Alex
is the, what are you?
The Associate Director
for Science?
>> Alex Young: That's correct.
>> Stephanie Marcus:
Heliophysics division.
But more, probably more than
dealing with all the data coming
in from the various missions.
He loves to talk
about what he's doing.
He's a great communicator.
That's his passion.
And he and his wife
developed a website
which you might want
to check out.
It's called oursuntoday.org.
And it has everything solar.
>> Alex Young: The--
thesuntoday.org.
>> Stephanie Marcus: Oh, sorry.
>> Alex Young: That's okay.
>> Stephanie Marcus:
Thesuntoday.org
and I think I will leave.
And please welcome Alex Young.
[Applause]
>> Alex Young: Thank you.
Let me, let me, let
me refill the water.
>> Stephanie Marcus: Okay.
>> Alex Young: Now
no, no harm there.
So. I figured it
would have been me
if it was going to be anybody.
So. That's why I didn't want
to have too much more coffee.
I always start getting shaky.
So thank you.
It's really great to be here.
I, I love this forum.
Except for the fact that
I have to stand still
in front of the podium.
But otherwise, this is
really, really exciting.
And so I encourage you,
if you didn't get any NASA
goodies, to get some outside.
But also to look at the
books, the journals.
There's a little
bit of my stuff.
But this is really not
about my work so much.
Today we're going to talk
about heliophysics in general.
What is heliophysics?
And in particular,
we'll also talk
about the new mission,
Parker Solar Probe.
Which was launched in
August of this year.
And I'm not going to tell
you too much about it yet.
I will get to it.
But I want to give you a feel
for what heliophysics is.
Kind of my slant on it
and why it's important.
Not just for its own science.
But for all of the
science that NASA does.
It actually plays a very
unique role in NASA.
And because of that, I
actually want to start off
with some imagery
that personally,
for me I think is the
most powerful imagery
that NASA has ever taken.
Some of you may be
familiar with this.
But what you're looking
at is called the,
the Hubble Ultra-D field view.
And so there was a spot in
the sky where if you look up,
you don't really see any stars.
Okay? Even in the
blackest, in the, in the,
in the darkest areas,
there are no stars.
But scientists pointed
Hubble into that little,
small piece of the sky.
Not much more than
maybe this big around.
And stared at it for
a long, long time.
Many, many weeks.
And what they found was this.
Everything you see in
this image is a galaxy.
Not a star, but a galaxy.
So ten thousand galaxies can
be seen in this little tiny,
tiny swatch of the sky.
And to think about it.
Every single one of those
galaxies contains hundreds
of billions of stars.
So these galaxies are
kind of like the atoms
or the molecules
maybe, in our body.
But of the universe.
But the fundamental
part of these,
the fundamental particles, just
like the fundamental particles
that make up our bodies,
our subatomic particles.
The fundamental particles
here are in fact stars.
Billions and billions of stars.
Make up these billions
and billions of galaxies.
So ten thousand galaxies in this
little, tiny swatch of the sky.
If we look everywhere
over the whole sky.
We're talking hundreds
of billions of galaxies.
Each containing hundreds
of billions of stars.
And on top of that,
containing billions and billions
and billions of planets.
In each one of those galaxies.
More than the stars.
So just mind-boggling.
So the, this is to me one of
the most awe-inspiring images
that NASA has ever,
has ever recorded.
But the reason I focus
on this is because to get
down to the core
piece is the stars.
It's made up of these
fundamental building blocks.
And we have something
really special.
We have one in our
backyard that's very close.
And that we can see
in incredible detail.
And that's what I'm going
to talk about today.
Is our own star, the sun.
Now looking at it
from the ground,
we get beautiful
sunrises and sunsets.
But the sun itself is not that
interesting when we just look
at it from the ground.
Now, you've probably heard this,
especially during the
eclipse last year.
You should never look at
it with the naked eye.
Without proper filters,
proper protection.
Because it's in fact so bright.
And even if we were to say
look at it with a camera.
We just get this sort
of washed-out image.
Okay? Now, I can look at it
with a filter, the same kind
of solar-safe viewing glasses
that we had for the eclipse.
And even there, I really just
see kind of a yellow ball.
A simple, plain ball.
It's not very interesting.
Not very exciting.
Maybe we might see some
little spots on it.
Some black spots.
We call those sunspots.
When they're really big,
when the sun is active.
And the sun actually
has an activity cycle.
An activity season
of roughly 11 years.
And when it's most active,
you can in fact see
some of these sunspots.
When you look with the
solar viewing glasses,
you can see them
from the ground.
But there is one special
time from the ground
when we can see the sun
in all of its glory.
Or at least a lot of its glory.
And some of you maybe
were lucky enough.
Who saw the total solar
eclipse last year?
Now who saw totality?
Okay, wow.
That's a lot.
That's a good percentage of
those who saw the eclipse.
This is what we see
during that special time.
When the moon is the
same size in the sky.
The same apparent size,
and blocks the sun out.
Blocks that bright disk which is
in fact a million times brighter
than the outer part of
the sun's atmosphere.
And this is what's revealed.
All of that structure.
I so want to just
run over there and,
and sort of touch this
and talk about it.
But all of this structure
is real.
These are in fact magnetic
fields coming out of the sun.
the same magnetic
fields that you can feel
when you put a magnet
on your refrigerator.
That invisible force.
But in fact, coming
out of the sun,
the sun's very atmosphere
lights it up and traces
out these magnet fields.
These are coming out of
those sunspots, in fact.
Because those sunspots
we see are these regions
of intense magnetic field.
And this is what's
driving the sun.
But that brief moment during a
total solar eclipse we see this
kind of detail in structure.
And get a glimpse that the
sun is way more interesting
than maybe we thought.
But let's step outside
of the atmosphere.
Go up above and look at the
sun with telescopes from space.
And we can now see it
in even more detail.
In even more interesting light.
There's a lot of light
that doesn't make it
through the atmosphere.
Which is good for us.
X-rays, gamma rays, ultraviolet,
extreme ultraviolet.
Our atmosphere is actually
quite thick and protects us.
But we can't see the sun in
those wavelengths of light.
And it turns out that's where
it really gets interesting.
So let's look at
the sun from space.
In extreme ultraviolet.
This is what it looks like.
Now this is anything but
simple, and anything but boring.
You see there are these
flashes that are occurring here.
In fact, these bright
patches are
where the sunspots are, okay?
When I look at them in
more energetic light:
x-rays, ultraviolet.
They're actually
bright, they're not dark.
Because they're really hot,
and I'll talk more about that.
But you see there's a flash.
Which is a solar flare.
It's a sudden release of light.
Enough energy is
released in that flash.
To power the world
for 100,000 years.
Okay? And at the same time,
you see there's this
flicker across the surface.
That's in fact a wave traveling
millions of miles an hour.
There's a giant blast wave
when this flare happens.
And it's pushing material
away and out into space.
Billions of tons of material,
something we call a
corona mass ejection.
It's being pushed out
by the magnetic field.
And in fact is it just, is
just as energetic as the flare.
Because it's moving so
fast and so much stuff.
It actually has the
equivalent amount of energy.
And this flare, this
light and all
that material is
filling the solar system.
And they're even driving
these huge shockwaves
that accelerate particles
to close to speed of light.
And we get these
blasts of particles.
So all of this stuff
is traveling
through the solar system.
And it's happening to
some degree all the time.
Little tiny ones are
happening all the time.
And then every so often, we
have the bigger one like this.
But with these telescopes, I
can in fact look at the sun
at ten different
wavelengths of light.
So here is the sort of
simple sun we're used to.
Just the, the yellow ball.
You do see some sunspots.
Okay? Now if I can, oops.
Supposed to start a video.
And it's not starting.
There we go.
Okay. Now I'm taking
little slices
and showing actually
other wavelengths.
Starting with ultraviolet,
extreme ultraviolet.
All the way up into the
very edge of x-rays, okay?
I can take these
images simultaneously.
And you see that, see there's
where the sunspots are.
But now they're bright.
And you see as it moves around,
how much different the
different wavelengths of light.
How different the sun is.
And in fact, what you're seeing
in different wavelengths
of light.
As we go from the surface
which is about 6000 degrees
up to 10,000 degrees, 80,000
degrees, a million degrees,
up to about 10 million degrees.
So as we go up into
more energetic light.
We're in fact looking
at higher temperatures.
But also, as we're doing that,
we're also looking higher
up in the atmosphere.
So this is something
really weird.
As I go from the surface,
which is 6000 degrees.
And move up, it gets hotter.
That doesn't make any sense.
I mean, when I go up to a
campfire and stand up next
to the warm fire, and
walk away from it.
It gets cooler.
When I move away from the
heat source, it gets cooler.
That's what we're used to.
Well, that's not
what's happening here.
On the sun, as you go
higher in the atmosphere,
it goes higher in temperature.
So this is one mystery about the
sun that we're going to explore.
But what else is going on
that's kind of strange?
So here's another ultra--
extreme ultraviolet image.
You can see these are those
magnetic fields coming
out of the sunspots.
Again, they're normally
invisible,
but the sun's atmosphere
lights them up.
Okay? And all of this
material is heating.
And expanding away from the sun.
And in fact flows out into space
in what we call the solar wind.
So the sun's atmosphere
is getting hotter,
but it's also expanding away.
And is expanding super-fast.
Millions of miles an hour.
It's streaming away.
The solar wind is filling
the whole solar system.
It's carrying away
the magnetic field.
And it's interacting
with everything.
In fact, it creates a giant
bubble around the solar system.
I'll show you a cartoon of this.
So there's the solar
system, there's the sun.
And those particles
are streaming away
in that magnetic field.
And it creates a
protective bubble around us.
Protecting us from
interstellar space,
all the other stuff out there.
And that is the heliosphere.
So helio, for sun.
This is the sphere of
the sun's influence.
And heliophysics is the study of
the sun and the sun's influence
on everything in
the solar system.
Because in fact, all of this
stuff, this light, matter,
magnetic fields that are
streaming away from the sun.
Are interacting with
other planets.
With their atmospheres.
With the planet's
own magnetic fields.
With comets, asteroids.
Even the stuff and
people we put into space.
And so heliophysics is
the study of all of that.
And all of that interaction.
Now one of the aspects
of that is space weather.
And I'm not going to talk
a lot about space weather.
I actually gave a talk about
that a couple years ago.
But space weather is really all
of that exciting,
dynamic phenomena.
Those solar flares, those
coronal mass ejections.
And especially how do
they influence technology?
Because all of this
is electromagnetic.
And all of our technology,
our cell phones,
our satellites are
electromagnetic.
They're driven by
electricity and magnetism.
So all of this stuff
coming off the sun interacts
with our technology.
Now we're very protected
to a large extent here
on the, on the earth.
And it doesn't physically
impact us.
But it does impact satellites.
It can be, create a dangerous
environment for astronauts.
And in the most extreme case,
it can actually impact
our power grids.
So that's one thing
that's really important
about studying space weather.
When we get back
to the sun itself,
we want to understand
the fundamental things
about the sun.
So the first one being
why does it get hotter
as the atmosphere moves away?
And why does the solar
wind expand away?
And actually one of the
things it does is it
actually accelerates.
It gets faster as
it's moving away.
So that's another strange
mystery about the sun.
And then lastly, kind of
back to that space weather.
All of these huge explosions,
I'm going to show you real data
of what that looks like.
So there's one of those
explosions on the sun.
Material blasting away at
millions of miles an hour.
And if I zoom away
and look at the sun.
Blocking out the bright disc,
and kind of creating
an artificial eclipse,
this is what it looks
like from space.
So there you see that's that
material actually unwinding.
It almost looks like a
piece of string unwinding.
Because that's the magnetic
field in that material
which is all twisted up.
And it's unwinding
as it moves away.
So all of this, all of this
stuff from the sun, this energy.
Is filling the solar system
with energy and material.
And this is actually one
of the most beautiful
and obvious manifestations
of this.
It's the aurora.
So when I mentioned
that this material
and energy interacts
with a planet.
With its atmosphere
and its magnetic field,
when that helps in earth.
We get the Northern
and Southern Lights.
This is seen from
the, from the ISS.
This is actually over
the Indian Ocean.
So this is the Southern Lights.
But you see all of
those curtains.
Those are particles that
originated from the sun.
Interacting with the atmosphere.
And they're causing it
to get excited and glow.
We have oxygen and nitrogen
which gives us greens,
blues, and reds.
To create this aurora.
But this is just one of
the manifestations of all
of this stuff coming
off the sun.
Here is kind of what
it looks like.
If we could actually
see those particles.
We sit in this sea of
particles coming from the sun.
The solar wind and
then every so often,
there's one of these coronal
mass ejections which is like.
You can think of the solar wind
as sort of the background ocean.
And then these giant
waves on top of it.
Those are those coronal
mass ejections.
And that's what happens
when it passes by the earth.
In fact, here you see
the particles moving
around the earth.
Being kind of repelled
by it a little bit.
Because the earth
has a magnetic field.
And these particles interact or
are repelled by magnetic fields.
Some planets have magnetic
fields like the earth.
Some planets don't,
like Venus or Mars.
And so how they interact
is very different.
And very important
to understand.
Especially, for example, if we
want to someday move, go to Mars
and have people on
the planet's surface.
The environment is
very different.
But the big point here is
that space is not empty.
We often hear about the
idea of the vacuum of space.
With this sort of implication
that there's really
not much there.
But in fact, space is full
of all of these particles.
And electromagnetic fields
originating from the sun.
Interacting with all
the different objects.
And this is what
scientists found
out at the beginning
of the Space Age.
So 60 years ago, in fact, 1958.
Group of scientists led by
a man named James Van Allen,
launched Explorer I.
And that rocket traveled
through the outer parts
of the atmosphere.
Very, very high up.
Through something that was,
we had possibly some ideas
about called the
radiation belts.
And what we found out was
we flew Geiger counters
in space, basically.
And found out it
was full of stuff.
Full of radiation, a very
complicated environment.
So there's Van Allen.
And this was the
beginning of the Space Age.
The beginning of
space exploration.
And so what that group did
is they formed a, a team.
To put together a bucket list
of what are the big problems
we want to solve, okay?
And right about that same
time in 1958, this gentleman,
Eugene Parker, published
a paper.
Predicting the solar wind.
We didn't actually
know at that time
that the solar wind existed.
And he said it did,
theoretically.
He worked out what he said
are very simple equations.
I've looked at them.
They're not quite so simple.
But he's a really sharp guy.
[Laughter] But very
fundamental equations.
And just sort of worked it out,
and it just sort of fell out.
People didn't, a lot of
people didn't believe him.
He had trouble publishing
the papers.
But he stuck be what
he knew to be true.
And he published
this paper in 1958.
And then a couple years
later, sure enough,
some future missions showed.
That yes, solar wind exists.
And he predicted it in 1958.
And that was the
beginning of the Space Age.
And in some ways, the beginning
of modern heliophysics.
And in fact astrophysics.
One of the items on that
bucket list of things
that scientists wanted to
do was to go to the sun.
And we had other items,
like building a giant
telescope in space.
We have the Hubble.
That's an example of
the result of that.
And there's several other
things that were done.
So the last item that
hadn't been achieved
yet was sending a
spacecraft to the sun.
So why not?
Why hadn't they done that yet?
Okay? It's 60 years.
We've done a lot of
really cool stuff.
Why not? So this is
actually a little analogy by.
That I, that I, the project,
former project manager
for Parker Solar Probe,
Nicky Fox, likes to put up.
To kind of give you a comparison
of what was the leap
in technology needed?
To achieve this?
And some of you may
not even know what
that object is on the left.
[Laughter] Okay?
I think most of you do.
But surprisingly, there's
a few people that don't.
You don't know what it is?
[Inaudible] Okay, alright.
But that's a rotary phone, okay?
To an iPhone.
To an iPhone X, okay?
And the leap in technology
is almost indescribable.
Okay? I mean, just the iPhones
today are so much more powerful
than any computer that we had,
you know a few decades
ago, okay?
Which is kind of crazy.
So what are the challenges
that we had,
we had to get past
in order to do this?
In order to send a
spacecraft to the sun?
So I'm going to go
through a couple
of the technical challenges.
This is a mission that
has been thought about.
And versions of it have
existed for these 60 years.
So this is not something that
was just recently put together.
People have been
trying to develop plans
for this from the beginning.
I remember in graduate
school going to a conference.
To a version, to see a
version of solar probe,
as it's been called in the past.
And I've seen, I don't
know how many iterations.
They're, they're many tens of,
of substantial iterations
that have led to.
What eventually became
called Solar Probe Plus.
Before it was renamed, okay?
And the first part is heat.
Okay? And that's actually really
one of the key issues is heat.
Now you may think, "Well, yeah!
The sun is hot."
Okay? It's really hot, okay?
But it's actually a
little bit different
than what you might think.
So we talked about the sun's
outer atmosphere called
the corona.
That in fact gets to be
many millions of degrees.
But that's actually
not the issue.
And I want to explain
that because this is a
little bit of difference.
Between the idea of heat
and temperature, okay?
Temperature tells us how
fast things are moving.
So when I measure the
temperature in this room.
I'm actually getting a measure
of how fast the air
molecules are moving.
So when it's measures
as 65 degrees, that,
I can actually connect that.
With how fast the
molecules are moving.
And the molecules, well actually
there are not molecules.
But the atoms and the, the,
the subatomic particles
in the corona.
Because in fact it's so
hot that normal molecules
and atoms don't exist.
Everything breaks apart.
Because they're moving so fast.
They're in fact moving
the equivalent
of many millions of degrees.
That's really, really,
really fast.
Okay? But the difference
is in this room.
While it might not feel like it,
the atmosphere is very thick.
There are almost an
incountable number
of particles in a
space like this.
So if I think of a, a
box about this size.
There are trillions upon
trillions upon trillions upon
trillions of particles.
Some of you may even remember
things like Avogadro's number.
Ten to the 23's-- 6.02
times ten to the 23.
Okay. Times a lot, okay?
That's a big number, okay?
So there's a lot
of particles here.
And there's a lot of
particles to transfer heat
to my body so I can feel it.
But in the corona, in
an equivalent-size box,
there's a handful of particles.
Like I can count them.
Maybe five to ten
particles in a small box.
That's not very many particles.
And so even though
they're moving super-fast.
They have really
high temperature,
but it's very difficult
to transfer the heat.
Okay? And so the way heat is
transferred is transferred
by conduction.
Convection, like bubbling water.
You see material moving.
The other way is by radiation.
Okay? By radiating energy.
When that's normally not
a very efficient way to,
to transfer heat.
But actually here, the sun
is really, really bright.
And there's a lot of radiation.
A lot of light.
You can go outside on a sunny
day, and you can feel how,
how strong the sun is.
Well imagine if you're actually,
if it's 50 or more times that.
Okay? Because you're
so much closer to it.
So the front of the spacecraft
is getting so much radiation,
that's actually what's
heating it up.
So the first part is there's
a heat shield that has
to be very highly reflective
to reflect most of
the sunlight away.
So that's the first part.
But it's also made of a special
material, carbon composite,
foam and threading
that's about this thick.
And so the radiation imparts
enough heat to the front
of the spacecraft
that the temperature.
The physical temperature on
the front of that spacecraft is
about 2500 degrees, okay?
Which is pretty hot.
That's hotter than most
substances can exist here
on earth.
Behind that heat shield,
it's about 85 degrees, okay?
So that's the first part of the
technology that was developed.
Another one is the solar panels.
So you think, well solar panels?
It's great.
We can power the
thing by the sun.
We're really close.
We get a lot of energy.
That's awesome.
However, solar panels are
made of silicon material.
Have you ever put your iPhone
in the car, and it gets really,
really hot and turns off, okay?
Electronics don't like heat.
So solar panels don't like heat.
And in fact, they fold them
in when they're really
close to the sun.
But also there's a radiator
system that's cooling it.
And these engineers
are really clever.
They came up with a way
to cool using a radiator.
With just a gallon
of regular water.
But what they figured out is
the way to arrange all this
to make it very efficiently
take heat away.
So that's, that's
pretty amazing.
And in the last bit
that they did.
And this also seems kind of
simple, but in fact it's not.
Is the original ideas were hey.
We've got to get
close to the sun.
It's actually really difficult
to get close to the sun.
I mean, it's, it's pretty easy
to get straight into the sun.
But then your mission
is pretty short.
[Laughter] Okay?
I want to fly by the sun.
I want to fly through
the atmosphere.
I just don't want, I don't
want to just go straight to it.
Because them, I'm
over, it's over.
So the problem is, is that
when you leave the earth.
And this is where it's
really hard to stay still.
But the earth is
moving at many tens
of thousands of miles per hour.
As it's, as it's
orbiting the sun.
And so when I shoot
myself off the earth.
I only, I don't just
have motion forward,
but I have motion this way.
So I've got to slow that down
so that I don't overshoot.
Well, the original
idea was let's use one
of the giant planets,
like Jupiter, okay?
To use the gravitational
assist to slow us down.
And then work our way in
closer and closer to the sun.
But it actually takes a lot
of energy to get to Jupiter.
So you have to have a
huge rocket for that.
And a lot of the constraints
on how much material,
how much rocket fuel,
and all that.
Were really prohibitive to make
this mission cost-effective.
I mean, you can do anything
if you have enough money.
But you know it's not really
practical to spend billions
and billions and billions
of dollars on one thing.
Okay? So a very clever scientist
came up with the idea of hey,
let's use a smaller,
closer-in planet.
And he figured out how
to do it with Venus.
So we use Venus to
slow, excuse me.
To slow Parker down.
To get closer and closer.
And I'll show you what
that orbit looks like.
So I skipped this
image, but this is the,
that's actually the
special, unique radiator.
For the solar panels.
So I want to talk a little
bit about the distance scales.
Before I talk about the orbit.
Now we're 93 million mile--
on average, we're 93 million
miles away from the sun.
Okay? So how close
will we get, okay?
We're actually going to be
less than four million miles.
Now, that doesn't seem like
a really, really close.
But when you think
about it in terms
of being 93 million miles away.
Less than four million
miles is pretty close.
It's only a few percent,
the distance
between the earth and the sun.
But I have a nice little analogy
to put this in perspective,
okay?
So let's think about
a football field.
Think of the sun at one end of
the football field and the earth
at the other of the
football field.
Now, we're interested
in the corona.
There are those coronal
loops, for example.
And those come out to about
the 15 yard line from the sun.
Mercury is at about the 35.
Venus is over on
the, on earth's 28.
Okay? So there are
those coronal loops.
We want to, we want to
get close into those
to really measure
stuff from the sun.
We've sent a spacecraft
in the past helios.
And it got close.
Okay? Within the
orbit of Mercury.
But Parker Solar Probe -- .
>> It's in the red zone.
>> It's going to
the four-yard line.
Okay? That's really close.
That's really close.
So that's what we have
to do in order to get
to where we know this
interesting physics
is happening.
But we do know from the studies
that we've done remotely.
We've been looking at the
sun in incredible detail.
But from a distance.
With imaging.
And you can do a
lot from a distance.
But there's a point at
which you need to go
where the action is, okay?
So we think about
across the room.
I mean, I can use tools
to measure temperatures
across the room these days.
I can learn a lot by, let's say
there were curtains over there.
Saw the curtains were moving.
I could tell you something about
the airflow through the room.
But there's certain details
that I really can't figure
out unless I walk over to
the other side of the room.
And actually measure with
a thermometer right there.
And actually measure the,
the, the curtains in person.
To see which way
the wind is blowing.
And all the [inaudible]
that I need to do.
And so that's what's
happening here.
To understand why is the
atmosphere getting hotter?
What are the detailed
physics of that?
What is the phenomena
that's helping
to release all this energy
and create these solar flares?
These coronal mass ejections.
This really explosive phenomena,
driving space weather?
And just causing the
solar wind to expand away.
We know now there's a region
where all this is happening.
And it's happening right
where Parker is going to go.
And now we're going to
go there, in person.
And be able to physically
make measurements right there.
We're not just looking at things
from a distance, but we're going
to measure how fast
things are going.
Which direction they're moving.
The details about that
environment where all
of this interesting stuff
is happening on the sun.
Okay? So in preparation for
the mission, I'm just going
to show you some cool pictures.
There's a lot of fun stuff
that went on, you know when,
when NASA and NASA's
partners prepare a mission.
There's an insane
amount of testing done
on every individual part.
On the spacecraft itself.
And so these are some
examples of the various types
of environment testing
they were doing.
They packed it all up.
Sent it down to Kennedy
Space Center.
Then once they got there,
they actually put the
heat shield on at Kennedy.
That was something
that was very delicate.
They didn't want to
ship it together.
So this was all put
together in a large building.
Put on top of a rocket.
Put on top of the
biggest rocket we've got.
The biggest rocket
that NASA has, okay?
It's called a, a Delta Heavy.
And it also has a
special booster stage.
So you got this tiny little
thing next to the rocket.
It's not much bigger than a
small car on this giant rocket.
With these huge engines.
Because that's what we need to
get this into the orbit we want.
So we can start using Venus
to work our way in
closer to the sun.
So that was the original
launch window.
In fact, the launch
first, the launch,
when it first started
on August 11.
The first day everything
was seemingly going well.
They have this long checklist.
They've got to go through
everything, and even every item
in the checklist
actually has tens.
Or more things within
those items.
Got all the way down,
and there was a,
there was a little anomaly.
A signal that said
something wasn't quite right.
And the window is very short.
Because in fact, we had
less than an hour every day.
Because we're trying
to go to Venus.
And they were launching really
early in the the morning.
Because at that time,
Venus was the morning star.
We're going in that direction.
So we had very limited time
period where we could launch it
and get it going to Venus.
First day, didn't make
it to the checklist.
Had to recycle.
Next day, everything
went off flawlessly.
So what does that look like?
Unfortunately, I don't
think I have any sound.
Let me see.
But I just want you to
see what this looks like.
>> Ten, nine, eight,
seven, six, five, four,
three, two, one, zero.
Liftoff of the mighty
Delta IV Heavy Rocket
with NASA's Parker Solar Probe.
A daring mission to shed
light on the mysteries
of our closest star, the sun.
>> Alex Young: So
that was August 12.
It was an amazing day.
And so one of the things
that's really cool about this.
And I haven't talked
a lot about it.
But Eugene Parker.
So let me pause this for a sec.
So I want to step back
and talk about one
of the things that's
really unique about this.
Is when NASA launches a mission.
Typically, it has a name.
Solar Probe Plus, in this case.
And then once it's launched,
it's named after a person.
Okay? That's the typical thing.
Hubble, Chandra, all
these different missions.
But they're always people
that have, that are dead.
That are no longer alive.
This is the first time we've
actually named a mission
after someone who's still alive.
Eugene Parker is still alive.
He's 93 years old.
He's an Emeritus at
University of Chicago.
And he was at the launch.
So let me show you a little
bit more about the launch.
There he is.
>> Five, four.
>> [Woman screaming] Yes!
Wooooo!
[ Laughter ]
>> Wow! Go, baby, go!
[ Crowd Screaming ]
>> Alex Young: That's his
son, and that's his wife.
And that's the project
scientists.
[Laughter] Nicky Fox.
[ Applause ]
>> Here we come.
Wow.
>> Alex Young: So.
This is the culmination
of his life's work.
And I'm hoping he'll get
to see a lot of the data.
Because we're working our way.
We've launched.
And in fact, it's going to take
several years to get there.
We make 24 orbits
around the sun,
each time getting
closer and closer.
And during that time,
we actually pass
by Venus seven times to
give us the continued boost.
To sort of slow us
down and allow us
to get closer and closer.
And I'm going to show
you some, some animations
of what those orbits look like.
And I'll show you
where it is right now.
But the cool thing is
that we've passed Venus
on our first Venus flyby.
That happened in September.
And then we actually
passed by the sun.
So we've made our
first pass by the sun.
So it's a little bit
bright over here.
I'll show you some
other imagery.
You might not be able
to see it too much.
But the red, there's
the orbit, okay?
And there's Venus.
So you see, it doesn't encounter
Venus every time it makes one
of those orbits.
But every so often.
So let's, let's actually look
at here's what those look like.
So the closest approach
to the sun is called
perihelion as in sun, helio.
Okay? And there's the
first close approach
which happened starting
October 29.
So November fifth was when
it was at its closest,
on its first close approach.
And then you see there
was its first Venus flyby.
Now on its way to Venus,
one of the things it has.
And I'll talk a little bit more
about the different
instrumentation on there.
But one of the types of
instruments is a camera
that looks out to the sides.
So that when it's flying by the
sun, all the stuff coming out,
it can actually image it.
Visually see it.
So we tried out the camera.
What we call the first light.
So any time an instrument
gets data,
even if it's not
necessarily taking pictures.
We just call that first light.
But that comes from telescopes.
The first images they saw.
This is the first view
of the two cameras.
They have two fields of view.
That's the Milky Way.
But the point is to show you
how amazing that camera is.
You see all the detail.
Because it's going to be
able to look at these,
these relatively small things
streaming away from the sun.
It also took another picture.
That's the earth.
It's looking back at the earth.
So again, this is the first set
of orbits and so on August 29,
it became the closest
spacecraft to the sun ever.
And it's just got,
started its mission.
And it's become the
fastest spacecraft ever.
When it makes its
closest approach,
3.9 million miles on orbit 24.
It will be glowing, going close
to 450,000 miles per hour.
That is almost half a
million miles per hour.
And it's a, a substantial
fraction of the speed of light.
So it's an incredibly
fast mission--
incredibly fast spacecraft.
So another aspect of it.
Not only do we have
this unique technology.
So first spacecraft named after
someone who's still living.
It's already made these
incredible achievements.
But it's also the first
fully autonomous spacecraft.
Now why is that important?
Well, when it's close
to the sun,
it takes about eight
minutes for light to get
from the sun to the earth.
So it takes about eight
minutes for a signal,
for a radio signal
to get that far.
So when it's traveling by the
sun, that heat shield has got
to be pointed at the sun,
protecting the spacecraft.
Any slight motion where part
of the spacecraft is no longer
under the shadow of
that shield would.
It would burn up.
Pieces of it would
burn up very quickly.
Okay? Because such
a harsh environment.
So the spacecraft has to
constantly be adjusting itself.
And a human being
could never do that.
Because human being
couldn't do it very quick--
as quickly as needed,
necessary in the first place.
But we can't communicate
fast enough to a spacecraft.
So that spacecraft has to be
able to take care of herself.
So she is fully automatic,
automated.
And this is the first
time we've ever done this.
So there's a lot of really
exciting firsts here.
But more important, we
are going to our own star.
This is the only star in the
universe that is so close
that we can see it in detail.
We can understand it
in the fundamental
physics that's going on.
We can't do that with any
other star in the universe.
Our star is in fact a laboratory
that allows us to study physics.
That we could never
study anywhere else.
And we can apply what we
know and learn from our star
to all the other
stars in the universe.
It's actually critical.
You know many of
you may be aware
that we now have
discovered thousands
of planets outside
our solar system.
But in order to really
understand those planets,
and understand the
environments they live in.
We have to understand
the environment created
by their stars.
And we do that by
understanding our own star.
So the mission, Parker
Solar Probe,
is not just a mission
about the sun.
It's a mission about
the universe.
It is a key to understanding all
of those fundamental
building blocks.
The stars everywhere.
Where are we now?
So you can actually go
to the Parker website,
and you can look.
So it's kind of hard
to see, but you can see
where it is on every day.
This actually is today's date.
I downloaded this today.
And you can see it gets,
where it gets closest.
And you see it gets
closer and closer.
And as it gets down
towards orbit 24,
there's where it's
closest to the sun, okay?
That's going to happen in 2024.
Year 2024.
Happens to also be the year
of another total solar,
total solar eclipse
in the United States.
So everyone needs to go to that.
Absolutely.
I'm going to skip this.
I wanted to show you this
before I get to questions.
To give you some perspective
of what is the spacecraft
going to see?
Now, you'll see a
lot of animations
with the spacecraft flying by
the sun like it's right there.
And it's not actually
that close.
But over here, this
is the sun we see.
This would be the
sun in the sky.
Same size as the moon, roughly,
which is we would
call a half a degree.
That's how big the sun is in the
sky, and how big the moon is.
So if that's the sun
we see here from earth.
This is the sun that
Parker Solar Probe sees.
Okay? Twenty-eight times
that, 28 times farther across.
Okay? And it's incredibly
bright.
It's going to be flying through
those giant loops that you saw.
Through the region where
the sun's atmosphere is
to the super, super
high temperatures.
And all that activity
is coming from.
So this is an amazing
mission that is going
to provide fundamental
understanding
of our star, of other stars.
But also understanding
of the phenomena
that drives space weather.
That impacts you and I, that
impacts our daily lives.
And could potentially,
at some point,
impact the larger society.
If we don't continue to,
to study and understand it.
So this is a really, really,
really exciting mission.
And over the next few
years, we're going to have.
Starts off with two
flies past the, the sun.
I think next year is
three passes in the sun.
And then from every
year on to 2024,
there are four perihelions,
four flybys the sun,
getting closer and closer.
And every time, we'll be
gathering more and more data.
And eventually we'll
get to that final goal.
And we will continue
to stay there as long
as the spacecraft has fuel,
which should be several
more years.
We won't get any
closer but we'll stay
at that closest every
time we orbit.
We'll be at that
closest approach.
And we'll continue to get
new and exciting information.
And certainly, we
will learn things
that we never had any idea.
That we, we're going to find
puzzles and questions that we,
we have never foreseen.
Because that's one of the
exciting things about science.
Is actually what you don't know
and what you don't
expect to happen.
And I know that's going
to happen from this.
So I want to stop there.
And then if I've got
some time for questions.
But I hope you got a,
have a good feel for kind
of what heliophysics is about.
And the beginnings of how we're
coming into sort of a new age
of understanding
the environment.
The space we live in.
And how our star drives that.
Thank you.
>> Thank you very much.
[ Applause ]
>> Stephanie Marcus:
I understood that,
so that's maybe a first.
[Laughter] Thank you.
But aren't you getting
some data tomorrow?
The first data?
I thought I read that.
>> Alex Young: Yes.
We're, so we'll, the team,
the science team will be getting
some, some new data coming up.
And there will be a press
conference next week.
So next week is the American
Geophysical Union meeting.
Which this year will be in D.C..
It's an exciting.
So this is an exciting
year for a lot of reasons.
It's the 100th anniversary of
the American Geophysical Union.
It's going to be the
first data from Parker.
This is 60 years after the
beginning of the Space Age.
Sixty years after his
fundamental paper, and 60 years
after the founding of NASA.
So this is a really,
really, really exciting year.
And I'm not even
talking about Apollo.
Because we're also getting
some anniversaries of Apollo.
This year is the anniversary
of-- and we just had it.
The anniversary of Earth Rise.
The first time we
saw the earth rise
up over the moon from space.
And it gave us a perspective
of our planet in a way
that we've never had before.
We saw it as a planet.
We saw it outside of it.
And that is one of the,
the pivotal moments
about our perception
and perspective
of our place in the universe.
So it's a, it's a
really exciting year.
Lot of cool stuff.
So yeah, next week
we'll be seeing some,
some first results from Parker.
And I didn't go into
the details.
There's going to
be a lot of stuff
about the different instruments.
But there's a whole
suite of instruments.
I showed you the camera.
But there are instruments
measuring the temperatures
of particles.
High energy particles.
Kind of the background
particles.
All of the electromagnetic
fields in the environment.
All these different parts of
what that environment is like.
These whole suite of instruments
will be giving us lots
of different data to
tell us what it's like.
Not just visually, but with lots
of detailed fundamental
information.
Okay, so I've talked again.
Questions in the back?
>> So what is the probability
for failure of the mission?
And what are the most
probable failure outcomes,
outcomes, I guess?
>> Alex Young: So what is
the probability of failure?
And what are the most
probable outcomes?
Well, okay.
So this is getting
into something--
I am not a systems engineer.
Now I'm not going to, so I can't
give you any, any hard numbers.
I will, actually I have
some colleagues here
that maybe can back
me up on things.
You know a lot about missions,
so I'm looking at you, Lou.
But let me just say that
the simplest way to put it.
Is that these engineers
have gone
through every possible scenario
and situation that they can,
they can have any control over.
There are always things
that could happen.
You know there can be failures
in equipment and electronics.
But again, these things are
tested and tested and tested.
Over and over again.
And certified and especially,
they all have a legacy
of being used on, in a
lot of other missions.
And I will say a lot
of the technology that's
used on this spacecraft.
HAs been developed in
the planetary community.
Which has incredibly
harsh environments.
Especially around places
like Jupiter and Saturn.
Okay? Which in some ways are
even more harsh than the sun.
Not all of it.
The, the, the actual physical
light is much higher in the sun.
But the particle
environment, the radio,
the radiation environment
is really, really severe.
So it doesn't give
you a specific number.
But the chances are
incredibly slim.
Now, if something were to
happen, there are backups.
There are contingencies.
For spacecrafts to handle a
lot of different situations.
I have worked with
many different missions
where some instruments
have failed.
Or some instruments, part
of instruments have failed.
That doesn't mean the
whole mission is over.
It does change the
science goals.
But in every case that
I have worked with.
And I know this is, this
is true for most missions.
It does not stop us,
the substantial amount
of science that's
coming in from it.
Okay? It may limit some of
the, the higher-end goals.
But the overall goals
have always been achieved.
In these sorts of missions.
I don't know if you want
to, if you have any,
any additional things
you want to say, Lou.
>> Well, the space
radiation environment is the,
probably the key.
>> Alex Young: Yeah.
>> The electronics are
radiation hardened to enable
to withstand the particle,
particle radiation of space.
The other thing is that if,
if the pointing mechanisms,
if the gyroscopes were to fail.
And that each shield wasn't
to be just exactly in front
or between the instruments
and the sun.
That could be a problem,
but that's all,
that's equally unlikely.
>> Alex Young: Right,
but that's the,
that would be the
most critical thing.
Would be pointing being off.
And the instruments not being
behind that heat shield.
Now one thing I will
say about this.
There are some unknowns here.
We are going to a region
of the sun we have
never been to before.
It's also a region that we
can't see certain things.
There, there have been
discussions about populations
of small bodies and
things like that.
Very close to the sun that have,
that are speculated to exist.
But we can't see them.
Because it's literally
too bright.
We try to see them
during eclipses.
But we don't really
know the details
of that environment
around the sun.
Within the, the orbit
of Mercury.
So there could be
potential issues there.
So I, not quite as definitive an
answer as I'm sure you'd like.
But you know.
So you had a question,
sir, over-- ?
>> Yeah, when it reaches
its closest approach,
will that be its
stabilized orbit?
Or will it decline
more over time?
And what, what is [inaudible]?
>> Alex Young: Well, when it,
when it reaches that orbit,
it will stay in that orbit.
Even after the mission ends.
And it's no longer pointing.
It will start to
break up as a cloud.
But orbital dynamics.
That cloud of space
stuff will continue
to orbit the same orbit.
It will eventually deteriorate.
And actually it eventually gets,
become part of the
corona itself.
It'll sort of be absorbed by it.
I'm not exactly-- I
don't remember exactly
where the aphelion is.
I'd have to look on there.
It's roughly around
the distance of Venus.
Okay? If you look at the orbit,
you see it's roughly
the distance of Venus.
And then Venus is
moving much faster.
[ Inaudible ]
Yes, so it will keep pretty
much the same orbit that it has
on that last, closest approach.
It will continue there
while it has fuel.
And even after it runs out
and, and its pointing is off.
It'll stay in that
orbit basically.
Yeah. So there was a question
there, and then I'll go to you.
>> Voyager I and II, they
said that they'd kind
of pass the heliosphere-- .
[ Inaudible ]
What does that mean when
you talk about solar winds
and what impact would
that have on the-- ?
>> Alex Young: Well so, so yes.
So you mentioned
Voyager I and Voyager II.
So that's, that is actually
a, actually you bring
that up is really good.
That's another sort of
monumentist thing about--
monumental thing
about this year.
Voyager I we believe has
already left the, the,
the sphere of the
sun's influence.
And now we believe
Voyager II is close to,
if not already, left it.
You know, it's not, it's
not a definitive place.
But a region.
But that is basically where we
are outside of the influence,
the primary influence
of the sun.
And we start to see
the influence
of the interstellar medium and
changes in the cosmic rays.
So the, the universe is full
of these particles called
cosmic rays which are coming
from supernova, exploding stars.
The sun and the heliosphere
actually pushes those
particles away.
It sort of acts as
kind of a shield
to deflect some of
those particles.
When the sun is most active.
When the solar wind
is at its peak.
It's pushing more out.
And pushing more
of those particles
out of the solar system.
And then when the sun is
less active, there are more
of those particles getting in.
So we're seeing the changes as
it moves outside that boundary.
Is that, does that
answer your question?
[ Inaudible ]
[Inaudible] means like
what is the solar wind
that it's encountering or?
[ Inaudible ]
Alex Young: I guess
I'm not quite sure.
Not quite-- .
You mean, the solar wind
out at the boundaries?
Is that what you're
referring to?
[Inaudible response]
Well, that's just sort of.
>> Assume that the
source was the sun.
>> Alex Young: Yeah,
the source is the sun.
So this, this all of these
particles are continuing out.
From the sun.
And they eventually
start to slow down,
and they reach, reach
this boundary.
And that's kind of where
the solar wind is no,
is no longer substantial.
No longer has any influence.
So I'm not sure if
I'm answering.
>> Yeah, [inaudible]
>> Alex Young: Okay, alright.
Yes. [Inaudible] Oh, okay.
I'm sorry.
So yes, sir?
>> Someone kind of
answered my other question.
But I wanted to ask
how is Parker, I guess,
going to help us
understand why certain-- ?
[ Inaudible ]
>> Alex Young: So what,
so why is, so why is,
so how is Parker going to help
us understand why the solar wind
accelerates, I think?
So the solar wind, because
the atmosphere is heating
up and expanding.
The solar wind naturally
expands.
Okay? That, that's
just a natural part
of the atmosphere [inaudible].
But what's happening
is in this region,
where Parker is flying through.
It doesn't just expand
normally with what you expect.
Now the, the big mystery is why
is the atmosphere hotter, okay?
Once we know that it's
hotter, let's not worry
about answering that question.
The fact that the
atmosphere's hotter,
we know that it should
stream away.
Okay? That, that's
going to happen.
But what is weird
on top of that.
Is that not only does it stream
away with, with what we expect
from that, those
million-degree temperatures.
But it in fact accelerates.
So it's expanding from the sun.
And then it speeds up.
That's weird, okay?
And so that's the part where
what we do know from other types
of observations and theory.
Is there's something happening
with the magnetic
field of the sun, okay?
Something is happening in
the solar atmosphere due
to the magnetic field.
That is causing those
two things to happen.
But we don't really
understand the details.
So that is why Parker
being there, actually being
where this is happening.
Where this acceleration
is occurring is critical.
So being again as I said,
where the action is.
Parker will be making
fundamental measurements
which answer the questions.
We have ideas.
We have a set of
competing theories.
But what we need to
do is pin it down.
Okay? So it's not that
we don't have any clue.
That's not the case.
We have clues, but we need some
more pieces to that puzzle.
And we are certain that what
we're going to learn from Parker
from being where this
stuff is happening.
Actually, I'll get to
your question real quick.
An analogy, one analogy that,
that I that Nicky
Fox likes to use.
Is if something happens
upstream.
Like somebody drops a
pebble in the water,
and there's a ripple
coming down.
You're father downstream.
You see a ripple.
You see something happen.
But you don't really know
where exactly did it happen?
And what are the details?
What was the shape of the rock?
That made the ripples
and this sort of thing?
So going to where the
pebble's being dropped
into the stream is
telling us more
than just seeing the
resultant ripples down the way.
Is that, does that
kind of make sense?
I think that, that's
really the key
of what it's going
to provide for us.
Yes, sir?
>> First thing about the
timing of the mission,
like scheduling of it?
Did it matter at all where we
are in the [inaudible] cycle?
>> Alex Young: Okay, so
the timing of the mission,
does it matter at all where
we are in the sunspot cycle?
That's actually a
really good question.
The, the immediate answer is no.
Now yes, it matters because
we have to think very, very.
We know that all this radiation
on the spacecraft is actually
pushing the spacecraft, okay?
There's actually pressure
from the solar wind.
From the radiation.
So where we are in the solar
cycle means that we can make,
we have to make adjustments.
So it's sort of like
you're going outside,
you're riding your bike.
And it's windy.
And you know if the
wind is blowing this way
or the wind is blowing that way,
you have to adjust how
you're riding the bike
to make sure you don't
get blown over or you know
if you have to speed up.
So knowing that is important.
But overall, does it
matter that it's windy?
No, that's actually okay.
We just for the planning,
we would need
to take that into account.
But it's actually exciting.
We're going to be getting
to the closest approach
near solar maximum.
And that excites
scientists because having one
of these big eruptions go off
while we're there is really
going to be a beneficial thing.
It's actually going to provide
new and unique information.
Yeah. Yes, ma'am.
>> Are these images going
to be seen in ultraviolet,
extreme ultraviolet light?
[Inaudible]
>> Alex Young: So the, so are
these images going to be seen
in other wavelengths
besides visible?
This particular instrument that
I showed that is only visible.
So those are only visible
in light images, yeah.
They had to make
certain decisions
about what they were
going to put on board,
given the limitations.
You know stuff is
expensive to put into space.
And the heavier it is, the more
there is to, the more cost.
And so they just had to
make some science decisions.
And they decided
that ultraviolet,
extreme ultraviolet
images were not necessary
for what they wanted to do.
Yes, sir?
[ Inaudible ]
It's not passing the same points
because the sun was,
the sun is moving.
It actually rotates
faster at the poles
than it does above and below.
But there will be no same-- .
Well, first of all because it's
not a solid body, there's going
to be no features or structures.
That will, that will last
substantially in any one place.
So it's not really going to be
coming back to the same spot.
It's all going to
be kind of mixed up.
Now you can see large sunspots.
Come back around.
They'll change and they'll
be in similar proximity.
But it would just
be total coincidence
if you actually hit one.
I'd have to look at the
actual timing, but they're,
they're not really
in sync at all.
Yes, sir?
>> I don't really know how
to ask this because I'm not
as smart as you are about it.
But you were talking about
temperature and the number
of particles in a box of like
atmosphere versus out there.
So what I'm wondering is these,
these prominences that fly off
from the sun because
they're so hot.
What would be their temperature
like as they get to the earth?
As they pass the earth?
Are they still really hot?
Or do they lose a lot of heat or
whatever the energy is that-- .
>> Alex Young: That's actually
a really good question.
So, so when these structures,
these prominences and which,
which we call, we call
them coronal mass ejections
when they leave the sun.
Are they still hot
when they get here?
They are. Okay?
The structures actually
have magnetic fields,
their own magnetic fields.
That break away from the sun and
so when you see this big blob
of stuff from the sun, these
coronal mass ejections.
They actually have their own
internal magnetic field, okay?
So they have internal structure.
And they do still have
that internal structure
does keep this energy.
So internally some energy.
Is it as hot as it was
when it was on the sun?
No. But are those
temperatures still hotter
than sometimes the
ambient solar wind?
Yes. But the temperature
scales are much different.
But yeah, there is some
energy that's kept inside
of that, that structure.
But the other thing is that
structure has expanded.
Those things expand
very quickly.
Even when you saw that,
that video that I showed
of that thing un, unwinding.
By the time that thing had
unwinded of that image.
That actually was
several times the size
of the sun just in length.
So they actually
form these clouds
that fill the entire
inner solar system.
So the temperatures are
nowhere near the many millions
of degrees that you
see on, in the corona.
But they do, they do, there is
still a lot of energy there.
And they also contain
kinetic energy.
So anything that moves
has kinetic energy.
The more mass there is and
the faster something is going.
The more energy it has.
So given that these things
are so massive, so huge,
and they're traveling at many
millions of miles an hour.
They have a lot of
internal energy in them.
And we see that.
We actually physically
see the earth's atmosphere
and the earth's magnetic
field shake
when these things hit the earth.
In fact, that shaking is what is
ultimately creating the aurora.
One of the things that, a
fundamental thing is physics is
if you have a magnetic field.
And you move it very quickly, it
generates electrical currents.
That's actually the principle
behind a generator, for example.
Or a motor.
So when that coronal
mass ejection comes
and hits the earth's
magnetic field.
The earth's magnetic
field rings like a bell.
So that magnetic
field is moving.
And it generates currents
in the upper atmosphere.
And those drive the particles
which give us the aurora.
When those currents are really
strong and we actually have a,
a very strong solar storm.
It builds currents on the ground
and can knock out power grids.
That's the concern for
large space weather events.
So these things have a lot of
energy, a lot of energy, yeah.
Yes, sir?
>> Regarding the solar wind,
you had an illustration early
on that showed what appeared to
be something of a current flying
over the solar system.
Where it buffeted on
one side, but it's kind
of strung out on the other?
Is there, is the tour
solar system moving
through the universe?
Or is there an actual
external current.
And just a quick
unrelated question.
Was there any accommodation made
for keeping it from crashing
into the Elon Musk's Tesla?
[Laughter]
>> Alex Young: So, so I'll
start with your first question.
Was there any, second question.
Was there any accommodation
to keep from crashing
into Elon Musk's Tesla?
I'm sure there was because I
really don't think they wanted
to hit a, hit a car with a
billion-dollar spacecraft.
I don't' think they really
cared so much about the car.
I can, I can, I can say that.
Given that there are hundreds
and hundreds of people
that have spent their
lives working on this.
That would really,
really be bad.
So. And I've seen spacecraft
and had colleagues
whose spacecraft blew
up and things like that.
And that's not a,
not a pretty sight.
So, so you other question.
So he said I had an an--
an animation or a-- .
>> It showed, it showed
that the solar system
that the solar wind-- .
>> Alex Young: Oh,
the, the, okay.
So the animation that I had
about the, the heliosphere.
What is your question
about that?
>> Is there actually
an external current?
Or is that-- ?
>> Alex Young: Yes, so is
there an external current?
Okay. Let me, let me
find that quickly.
Do I have time, okay?
>> I'm just curious if it's
coming from a specific source.
>> Alex Young: No,
it's actually,
that's actually a
really good question.
So this one?
>> Yeah.
>> Alex Young: Okay.
Yeah. So, so what you're
seeing there is well what, the,
the movement of it is trying
to illustrate the change
in the solar cycle.
Okay? So the solar
cycle, you know.
The, the sun goes from low
activity to high activity,
back down to low activity
over eleven years.
And so what you're seeing
there is the breathing
of the solar system.
Breathing of the heliosphere.
When solar activity's high.
It's puffed out.
And when it's low, you
know it kind of pulls in.
And so that's what
that motion is.
But all this stuff.
This, this heliosphere
is traveling itself
through the interstellar medium.
So this is like a
ship in the water.
And the fact that this
stuff is pulled behind it,
it actually makes kind
of, it makes a wake.
Because that whole system is
traveling through the galaxy.
And so it's traveling through
this interstellar material.
But it's very, very, you
know this is very simplified.
It's actually much more
complicated than this.
It's not this even simple
spherical structure.
Because it's being dragged back.
And you see the same
thing with the earth.
The earth has a magnetic field.
And if it was just sitting
still, it would be kind
of a nice symmetric shape.
But in fact, the earth, because
it's moving around the sun.
Has this long teardrop
shape, the magnetic field
because it's being
stretched by the solar wind.
So planets and solar systems all
do this sort of similar thing.
As they're moving
through different material
in their environment.
Yes, ma'am?
>> Do you have any instruments
on board that records sound?
Like solar wind?
>> Alex Young: Do we
have any instruments
on board that record sound?
Well, in, in a way we do.
So you know sound is just
compression of the air.
And that's, or the compression
of water, compression of metal.
Any of those.
A compression of
material is a sound wave.
And for us, the compression
of the air is picked
up by our ears.
But there are waves
of these materials.
You know we're, we're traveling
through these materials.
And there are waves generated.
And we are measuring
those waves.
We do have instruments
which will measure them.
They could in fact be
turned into sounds.
And I know that they will.
People do something called
sonification, actually.
We're interested in
that in my group.
Taking data and turning it
into sounds that we can hear.
So it's sort of translating it.
So you're, so anything
that's travelling
through stuff that's moving
technically has its own kinds
of sound waves.
And we do, we will be measuring
waves as we travel through it.
>> Stephanie Marcus: I
guess we should stop.
>> Alex Young: Okay.
Okay, can, can I
answer one question?
>> Stephanie Marcus: Sure.
>> Alex Young: Dr.
Young, my name is Z-e-o-s.
And I have two short questions.
IN our galaxy, the
planets, nine or so.
Do all the planets have the
most [inaudible], say the north,
the most magnetic pole?
All of them are aligning the
same, say one, two, three four?
[ Inaudible ]
>> So are all the
magnetic poles of planets
and the sun align the same way?
Well not all the planets have
magnetic fields, for one.
And they're not all
aligned the same way.
The poles are also changing.
The sun's poles change
regularly over 22 years.
Its activity cycle
is eleven years.
But actually every eleven years,
the sun's pole moves, reverses.
And then moves back over
the next eleven years.
So 22 year is actually
the magnetic cycle.
And then the activity
cycle's embedded in that.
The earth, for example, has
a cycle that's not regular.
And its field moves over
tens of thousands of years.
And other planets
do similar things.
So they're all very different
and very complicated.
So the, so the basic
answer is no.
The magnetic fields
are not aligned.
>> And my, my last question.
[ Inaudible ]
>> Alex Young: Well, I will
say that the, the calendars,
the modern calendars are
the bane of our existence.
Because they've made our
lives so complicated.
Because of the fact that
the moon cycle's different.
The sun's cycles are different.
The star's cycles are different.
And some, you know
bozo somewhere decided
to pick a particular set.
A calendar set-- .
>> Exactly how long ago
did they change that?
>> Alex Young: I don't
know when, I don't know
when the Gregorian calendar
and all that came about.
When, when was that?
>> Well, we know that the, the
Romans assigned a certain length
of days to the, to the
months, for example.
So August has 31 days
because Augustus was -- .
>> Why they came up
with the number 12.
I don't understand that.
Why they tried to change that?
>> It's a solar calendar
versus a lunar calendar.
>> Alex Young: Yeah.
>> You're thinking
a lunar calendar.
And ours-- .
>> Alex Young: It's a solar,
it's a solar calendar.
I mean, it, it, but it is,
it is an incredible pain
because of all these
different systems of the,
the different periods
don't line up.
And they make things
very complicated.
And interesting so.
Thank you.
>> Stephanie Marcus:
Thank you, Dr. Young.
[ Applause ]