- Good evening, and welcome to UW Space Place.
This is one of our Tuesday evening public talks,
and tonight I'm very pleased
to introduce Dhanesh Krishnarao,
who is an advanced grad student
in the UW Astronomy Department,
and he'll tell you a little bit about his own research.
But tonight he's going to tell us about space weather.
Dhanesh comes to us from American University in DC.
He's originally from Philadelphia,
so he's going to get a PhD here in astronomy
from Wisconsin
and work on things much bigger than space weather.
But he'll mention that in a few minutes.
But the really intimate astronomy of space weather
is what we're going to hear about tonight,
so please welcome Dhanesh.
- Thanks, Jim. Hey, everyone. I'm Dhanesh, like Jim says.
I usually just go by DK, so you can just refer to me as DK.
What I'm going to be talking today about is space weather,
which relates to our sun and Earth
and is something that can affect our everyday lives,
but before I really get into that let me just introduce myself a little bit.
Who am I?
I'm DK from UW-Madison, a grad student here.
If you're on Twitter you can follow me @DK_and a_bit.
I also have this conveniently named domain name,
www.astronomy.dk.
It's a Danish website that I bought.
It currently just redirects to my Wisconsin page,
but eventually will be kind of a fun website about me.
So what I do in Madison is not space weather.
I study our galaxy.
I'm a grad student here, I study the interstellar medium
and gas in our galaxy.
So really, who am I to tell you guys about space weather,
and why am I going to talk about space weather?
It turns out in a past life, as an undergrad
when I was in the DC area,
I worked as a space weather forecaster at NASA
through an internship program for almost three years.
So I was at Goddard Space Flight Center,
trained to do space weather forecasting,
and I'm going to start off by showing you guys
this admittedly very cheesy video
that was made of me and of what I did
as an undergrad following space weather.
This was done of me as an intern.
I'll go ahead and start that now and just kind of let that play through.
(upbeat music)
When I was four we went on vacation to like Disney World,
but the main part of that that caught my attention
was we went to the Kennedy Space Center
and when I was there I instantly fell in love with space
and astronomy and wanted to be an astronaut.
My name is Dhanesh Krishnarao.
I usually go by DK here.
I'm a rising senior at American University,
studying physics and math.
This summer my research project I'm working on
is to develop a system where spacecraft operators
can look up specific space weather conditions
near their spacecraft.
Space weather is getting really important now,
especially since there's more and more dependencies
on satellites and technology.
Different space weather events can cause radio blackouts,
knock out GPS systems.
So I think what I'm doing is going to really help out
with making sure that the least damage is done.
The most exciting thing I've done this summer
is probably one of the days
when all of the other forecasters were busy.
At this time no one else was free
'cause they were all attending conferences,
but they decided to put me in charge for the day.
I think Goddard's a great place to be.
Everyone's very enthusiastic.
Since last summer, as soon as I got here,
I loved everything here.
One of the main thing I liked here a lot
was being able to play ultimate Frisbee
every Tuesday and Thursday with all the NASA employees.
Overall, I just love being at Goddard.
Everyone here is very nice
and it's been a great experience.
So like I said, a little cheesy, It's a little bit weird,
but it talks about a lot of things that I'm going to be covering today,
so what space weather is, why it's important,
how it can affect our everyday lives
and why I'm going to be talking about it
is because it took up a large portion of my life
before I got here, and I really grew attached to it
and think it's very interesting.
Okay, so to get started, to understand space weather
we really have to start with Earth, our home.
We live on Earth, it's our planet.
I hope we all love it, I do.
So what space weather is is just broadly defined
as any kind of process or processes that happen
in space that can affect Earth
or the near-Earth environment.
That includes in orbit around Earth.
It even can include different planets in our solar system
or our moon, and it can also affect our everyday lives
on the ground and cause different effects
that we can see on the ground, feel on the ground,
and affect our electronics on the ground.
So it can have huge effects to our everyday lives.
What actually causes these effects?
For this, we go back to our sun.
I like to just start off kind of,
I'm sure you're all aware that our sun is huge,
but it's really hard to appreciate, really,
how big the sun is.
I still don't know if I can understand
actually how big it is.
This image here, you might see a label for the Earth.
If your eyesight is very good, mine is not,
you might see a little dot
that is showing the Earth to scale there in the corner.
You should notice that you can almost hardly see that dot
because the Earth is so small compared to the sun.
If you're a numbers kind of person,
you can fit about 1.3 million Earths inside of our sun,
but that can only help me so much understand how big the sun is.
I hardly can even tell you what $1 million looks like,
so who am I to judge what a million Earths is?
The sun is huge.
Here's a little bit closer up view,
so you might actually be able to see Earth here in the bottom corner.
And you can see the sun is much bigger,
doesn't even fit on the screen.
And what you're seeing here is an eruption
off of the surface of the sun,
and these massive eruptions of the material
on the surface of the sun and through the atmosphere of the sun
are what gets released throughout the solar system
and can sometimes come zooming towards Earth
and impact us and cause these space weather events.
You can see that even one small explosion, small,
is actually quite huge and enormous,
especially when you compare it to the Earth.
So these are the kinds of phenomena
that cause space weather.
If I was to break down what space weather is
and everything you need to know about space weather
in one slide, it would be this.
Everything starts on the left
and progresses over to the right.
We start with our sun,
where we have all of the energy that we get,
but also every now and then
the sun can unleash an extra burst of energy
through explosions.
These explosions of the atmosphere
can slowly propagate through space,
through our solar system,
and impact different planets and satellites
that are spread throughout.
Every now and then the Earth might be in the way
and could get impacted by one of these events.
But luckily, at least in this image,
Earth is protected by this magical purple blue shield.
So it's not really magic, it's the Earth's magnetic field
that is working as a way to shield us
from a lot of the harmful effects, but it's not perfect.
There's still some harm that can happen,
but also some beautiful sights that can happen from it as well.
So if you have ever seen the northern lights,
aurora borealis, that is an effect of space weather.
So that is something that happens
when these large solar events impact Earth.
So what I'm going to do over the course of this talk
is kind of just break apart this image
one piece at a time, show you each step,
what's happening at each step, and then end by talking about
what we can do and how we actually can forecast
and try and predict these events and protect ourselves.
So starting with the sun,
like I said, everything starts when the sun
unleashes massive amounts of energy
and starts the solar storm.
The first warning sign and event that we see
is what we call a solar flare.
So in this animation, within that red circle,
you might notice that it gets really bright.
This is a solar flare happening,
which is really just an intense brightening
on the surface.
When this happens it releases a lot of energy,
a lot of X-rays,
really high-energy light that can be harmful to us.
And that, of course, travels at the speed of light,
reaches us in eight minutes, and is our first indication
of something potentially bigger to come.
You might notice in this animation,
it's a little bit hard to see, but you might notice if you look carefully
around where that brightening happens,
that you see some what looks like puffy material
exploding off of the surface as well.
So that is the next kind of step.
Here's just another solar flare.
By the way, all of these images are from different satellites,
which I'll be talking about a little later as well.
And the different colors are looking at different wavelengths of light,
and each different color is telling us
a different temperature of the sun,
a different temperature of the gas and material that we're looking at.
So here the brightening is happening around here
where it zooms in, and you might also notice
nearby shortly after it gets very bright,
you can see some kind of loops erupting off of the surface
and leaving the influence of the sun.
What is happening there
when you see those kinds of eruptions
is what we call a coronal mass ejection.
The atmosphere of our sun is called the corona,
so it's just a coronal mass ejection,
meaning part of the corona
is being ejected out into the solar system.
Here is one case of that happening.
You can see this loop of material
exploding off of the surface of the sun,
and this usually happens because the sun
has very powerful magnetic fields
that sometimes get really tangled up and wound up.
From time to time they can get so tangled up
that they break and release their energy outwards,
and with that, some of the material off the surface
and within the atmosphere of the sun
will also follow along and be ejected out.
This animation is actually from that same still image
I showed earlier, where Earth was a tiny dot in a corner.
So it kind of just shows you the scale
of these eruptions that can be happening.
The kind of energy associated
with a single explosion like this
is millions and millions of times more powerful
than any of the most powerful nuclear bombs
we've ever created on Earth.
These are happening roughly two to three times per day
on the sun during solar maximum,
and maybe just like once every day or so
during minimum times of solar activity.
So they're happening all the time,
they're just also happening everywhere throughout the sun,
so they're pointed in many different directions
and every now and then can be pointed towards Earth,
and that's when we have to be careful.
We can also look at these coronal mass ejections
a little bit more carefully if we zoom out.
What this image is doing,
here's another coronal mass ejection happening,
going off to the right-hand side.
The way this camera is working,
it's from a satellite image, so it's looking at the sun.
The sun is located at the center behind
of that white circle, and you can see around it
it's pretty dark and that's because literally
the way to look at the much fainter atmosphere of the sun
without actually seeing the rest of the sun
is to just block it out with a disc
held in front of the camera.
It's literally just a disc being held in front of the camera,
blocking out the really bright part of the sun,
essentially creating our own eclipse
so that we can see the faint corona around the sun
and try and actually see these coronal mass ejections,
or CMEs, and measure them over time.
That's what can allow us to predict
how quickly they're traveling
and see when they might impact Earth.
Once they reach Earth,
it typically takes about two to three days
for one of these eruptions to reach Earth
if it was pointed towards us.
It will impact Earth, but like I said,
we have this so-called magical blue shield.
It's our magnetic field.
Earth, luckily, is essentially just a giant magnet,
so the magnet is able to repel
these energetic charged particles
that are coming off of the sun
from this coronal mass ejection,
and repel them across us.
It ends up creating this deformed magnetic field shape
where you'll see in a minute it looks more like a bullet,
and that's what really protects us
from the harmful effects of the sun, but it isn't perfect.
Some of that energy can still leak through.
You'll notice that when the storm passes by
it's kind of compressing the magnetic field
so it changes the boundary that we're protected at
so different satellites may be more or less protected
during one of these events.
This kind of shows the sun and how the magnetic field
is being compressed.
The yellow fluffy area there
is supposed to be one of these coronal mass ejections
as it expands through the solar system and impacts Earth.
You can see the magnetic field trails off of the screen to the left
as it's being compressed and pushed backwards
as it's deflecting most of the impact away from us.
But like I said, it isn't perfect,
so when we have these strong events
and the magnetic field gets compressed,
is when we have aurora borealis or the northern lights.
I have not been lucky enough
to be able to see these myself, unfortunately.
I know a few tricks to try and see them,
but you can see them sometimes in Wisconsin.
Typically the more north you go the easier it is to see.
They call it the northern lights.
They also happen on the southern pole.
But they're called the northern lights
because since our magnetic field originates
from the poles, the north and south pole,
that's where a lot of the energy that can get through
will funnel back into Earth.
I'll end with an animation that shows that process
happening a little bit better, but essentially the poles
are where that energy will fall into,
and the stronger the storm,
the stronger the coronal mass ejection
that's impacting Earth,
the farther down it can push that energy on Earth.
If we're ever seeing aurora borealis or the northern lights
from Wisconsin, that means that it's being pushed down
pretty far south.
So what that's telling you is that we're experiencing
a pretty significant space weather event here on Earth.
So there's no reason to be scared
and be running to the emergency room,
but it is something to be aware of.
If that's happening,
people a little bit more north of here,
especially if it's somewhere like Alaska,
Norway, Scandinavia,
they could be experiencing some of the harmful effects
that I'll get to soon.
The more south you see these events,
the stronger the event,
the solar storm that's happening.
Like I said, I haven't been lucky enough to see one of these yet.
I would love to sometime.
One trick that I have learned that has not yet worked for me
because I haven't been dedicated enough is, if you're ever taking a red eye flight,
especially one that's long, like, say, from here to Europe,
if you're flying from here to Europe,
try and get a window seat on the left side of the plane
and just stare out the window once it's dark
for as long as you can.
If you can get your eyes settled enough to the dark
that is out there, looking towards the north pole,
you should really be able to see these all the time.
The stronger the storm the more south these lights come,
but essentially it's happening all the time.
We just can't see it because it's way up at the poles.
The sun always has the solar wind
that's like a weak push of material
off the atmosphere going out into the solar system,
and that's always impacting us and it's not really harmful,
but it's still causing these northern lights to happen
all of the time, essentially, just very weakly.
Almost any time you are flying, you should be able to see it
if you go close enough to the north pole
on one of those polar routes.
If you're dedicated enough to stare for long enough, you might get lucky to see it.
It also helps that you're at high altitude,
there's going to be no light pollution,
except from whatever's inside the plane.
I usually just fall asleep if I try and do that too much,
so you have to really be dedicated,
but I do know people who have done it
and successfully been able to see
some of these northern lights.
Keep that in mind if you're ever taking
a long flight sometime soon.
Okay, so like I said, though,
unfortunately, space weather isn't all pretty.
There are a lot of harmful effects that it can cause.
We'll start at the top here.
First and foremost, astronauts are in space.
They're not as much protected from our atmosphere,
from our magnetic fields, as we are down on Earth.
If we start off from that first event I was telling you,
a solar flare,
it emits strong, powerful radiation like x-rays,
and that travels to us at the speed of light.
We can't predict it, we just see it
and that's our first warning sign.
X-rays aren't good for us.
They can cause mutations in our DNA.
If you're an astronaut in space,
you're at risk for that extra radiation.
Here on the surface, our atmosphere
blocks out most of those x-rays
and it's not going to cause any harm for us.
But the farther and farther you get up in elevation,
the more chances there are for those x-rays
to reach through and impact us.
So if you're an astronaut, say, doing a space walk
and servicing the Hubble Space Telescope or anything,
and one of these solar flares happens
which we can't really predict,
you're at more risk for extra radiation absorbed
and it's just never a good thing.
Apart from that, the radiation and the intense flight
can also just damage satellites.
It can damage the solar panels on satellites
that are providing their power.
That's bad for us here on Earth
because those satellites are what give us our GPS signals,
our telecommunications.
A lot of our everyday electronics
rely on satellite technology,
and they could be harmed
just initially from the flare itself.
Most of the satellites, luckily, are going to be within
the protection of our magnetic field.
Those keep them generally protected.
That's also true for the astronauts.
That keeps them generally protected
from the biggest part of the impact.
Though, like I said, the stronger the storm,
the more it's going to compress that magnetic field,
and every now and then some of these satellites
might poke out beyond the influence of that magnetic field,
and that's going to leave them at greater risk for damage.
It can actually fry instruments on the satellites,
knock out them entirely,
and destroy satellites entirely
that we may need to heavily depend on.
And GPS satellites are especially vulnerable
because they are at really high altitudes above
so that they can always be stationary above us.
The farther up the satellites, the more at risk it can be.
Closer down to us,
so these events, when they're happening,
can cause currents in our atmosphere,
and that will interfere with our communications.
So if we have radio communications,
whether that's communicating with a satellite in space
or just radio communications here on the ground,
so your FM radios,
if you're trying to talk between a plane and ground control,
all of that can be affected and disrupted
by one of these events.
More kind of everyday life-threatening, I guess,
not life-threatening, but a bigger threat to us
is on the ground it can also cause currents
to flow through the ground without any source.
When these powerful events are happening,
it's a lot of chaotic magnetic fields,
which can induce currents
and damage electronics here on the ground.
Ultimately what it can do
is if you have a really strong storm,
it can cause blackouts across the entire country.
If you have a strong enough storm,
it really could knock out power from DC to California,
all throughout continental US.
And it's not just like your everyday power outage,
it goes out and will come back on.
What's causing the ground power outages
are actually the transformers being overloaded
and essentially frying.
You have to replace each and every one of those transformers,
which is not an easy task.
We don't really have that many spare transformers available.
It's just something that, if it were to happen today,
would cause ground power outages for weeks
or even a month,
and you can imagine how devastating that would be,
whether it's to your everyday lives.
I mean, government infrastructure would have to close down.
Hospitals need electricity for their patients.
These are some of the reasons
why space weather is so important
that we keep an eye on it, keep track of it,
and try and protect ourselves.
There are ways to keep ourselves protected.
If we see one of these events happening,
we can shut off a lot of our instruments,
a lot of our electricity.
If we do that ahead of time it can protect all of the transformers
and all of the instruments and electronics and computers we have
to try and keep them operational as much as possible
and limit our impact from the damage.
Okay.
Pretty recently, space weather's been picking up
a lot more attention, whether that's in the media,
within the government.
I worked at NASA doing space weather forecasting.
My task was to monitor daily real-time conditions
from satellites, and when something was happening,
so when I detected one of these coronal mass ejections,
I'd have to measure what was happening,
run a model to predict when it might impact Earth,
how severe that impact might be,
and then the important part was send out alerts.
Those alerts would go out to NASA
so that spacecraft operators
and our astronauts can be safe.
We also send out the alerts to the Air Force
and other private industries
that operate different spacecraft.
The Air Force especially is an interesting
forecaster of space weather.
They have their own independent team
that also monitors space weather 24/7.
The reason for that is because during the Cold War,
a giant solar storm almost caused a nuclear war.
And you might not think that makes much sense,
but some of the effects that a space weather event
here on Earth can cause
can be misinterpreted very easily.
It causes chaotic miscommunication,
changes in radio signals, ground power outages.
Things you might expect if maybe
you were getting attacked by someone.
In 1967 we really were very close
to falsely interpreting a space weather event
as the Russians launching nuclear weapons against us.
I mean it went as far as the president getting ready
to retaliate and strike back.
Luckily 1967 was when space weather was starting to develop
as a field, and the Air Force was already aware of it
and actually starting to monitor the sun.
They were able to quickly say, hang on a second,
take a step back, we think this isn't a nuclear war.
There actually was this big solar flare
that happened a couple days ago.
It could make sense that that
is what's causing this disruption.
It turned out to be the case, so we're still here.
We can thank the Air Force
and their space weather team for that.
But it shows just one of the ways why our government
is also very interested in space weather
and why it's such a valued program.
The internship I had was an NSF-funded internship.
The department I worked for is known
as the Community Coordinated Modeling Center.
It's really just a fancy name put together
to express that it's a larger community,
more than just NASA
that is supporting the activities that they do.
So it's funded by NASA.
There's actually White House grants
that directly go into it.
The Air Force and military and also private industries
that operate a lot of spacecraft
provide the funding for that specific subsection of NASA
to operate their space weather forecasting system.
Okay.
So what can we really do about space weather?
We know that it's happening, I showed you how some of the ways we see it happening,
but how can we actually do these forecasts?
How can I make these predictions
when I see these events happening,
and warn someone of the harm that could come?
If we think about how we do it on Earth,
what we need is data, we need to look at something
and get information,
and then we need a model, something that we can use
to predict what might happen in the future
based on the information we know
that we've seen or is currently happening.
So on Earth, we have weather forecasts.
You probably check it every day.
On Earth, we're lucky we have a lot of satellites
looking down on Earth, gathering a bunch of data,
a bunch of different wavelengths and types
and feeding into these models that are predicting
wind, pressure, all of these different readings
that we have here on Earth.
You probably have realized that the weather predictions
you get on a daily basis are not that great.
So, it's really difficult to do this,
and we have a lot of information to go off of
when we're looking at weather on the ground here on Earth.
You can imagine how difficult it might be
with space weather, where we have to predict
weather events happening on the sun
that, remember, is so ridiculously huge
you can't even imagine how big it is.
We have to rely on information we're getting
from images from spacecraft, which aren't that frequent,
and there's also only a limited number of spacecraft
that we have that are concentrated on looking at the sun.
So really, working with the minimalist amount of data
to try and inform our models
when we're doing these space weather predictions.
But it turns out we still do a pretty good job.
There's a lot of improvement that could be done,
which is why space weather's such an active area
of research today.
What do we have looking out at the sun?
Like I said, we really do rely on satellites
to get constant 24/7 monitoring of the sun.
What this is showing is
many different satellites in orbit around Earth.
You might notice there are some
that are doing standard Earth orbits,
some that are really elliptical,
some that look really, really funky.
There are often pairs of satellites
that seem to be traveling together.
A lot of those missions are either looking at the sun,
looking at Earth, or just kind of monitoring
the conditions in space around Earth.
Remember, space weather refers to processes in space
that affect Earth or the near-Earth environment.
A lot of these are going through what we call the magnetosphere,
which is that zone of influence of our magnetic field
that is protecting us, and getting real-time measurements
of how the magnetosphere is behaving,
how our magnetic field is actually interacting
with the solar wind and these coronal mass ejections
as they're impacting Earth
and seeing how it's being compressed.
There's also a couple satellites we have in orbit around the moon,
which are what's on the bottom of the screen now.
We have lots of different places to get data.
It looks like a lot here,
but if you think about how many we have
looking at Earth for our regular weather data,
it's very, very tiny.
One of my favorite satellites
is the Solar Dynamics Observatory, SDO.
A lot of the best-looking images and animations
I've been showing you guys of the sun come from SDO.
It's in orbit around Earth.
It's always stationed so that it is in communication
with one dedicated large radio dish
that's in, I believe, New Mexico.
It's always talking to Earth, always looking at the sun,
sending us pictures every roughly 30 minutes
at many different wavelengths.
And the reason it's my favorite is because
it's looking at the sun at so many different wavelengths.
This mosaic of images stitched together
is a picture of our sun,
but at a bunch of different filters,
looking through a bunch of different filters
at very specific colors and wavelengths of light.
And each different panel there, each different color,
is telling us a different piece of information.
It's letting us look at a different layer of the sun,
a different temperature of gas that's around the sun
and probe different events and mechanisms
that are happening.
Some of these wavelengths are really good
for seeing the solar flares happening
when it gets really bright
and giving our first predictions of what's going to happen.
A few of these wavelengths,
especially that orange-colored one,
are really good for seeing those coronal mass ejections
where you can see filaments actually rising
off of the surface and going out into space.
All of these are useful for a different purpose,
and you really do rely on SDO a lot
to do these space weather forecasts.
The nice side perk is that it's really high resolution.
It gets really good images of the sun, they look great.
Makes great posters.
Another really important mission for space weather
is what we call the STEREO mission,
believe it or not, STEREO is an acronym.
I don't actually know exactly what it stands for.
I believe the first S is stereo,
so it's an embedded acronym within itself.
You might notice that astronomers really like acronyms.
STEREO-A and STEREO-B here
stand for STEREO-Ahead and STEREO-Behind.
What this image is showing is the sun at the center,
Earth at the bottom,
and STEREO-B and STEREO-A up near the top.
The way these satellites were designed
is so that they are in orbit around the sun,
just like the Earth, but STEREO-A, STEREO-Ahead,
is going slightly faster than Earth in orbit.
It's slowly leading ahead of Earth
in its orbit around the sun.
And STEREO-B, STEREO-Behind,
is slowly lagging behind Earth
and going behind in the orbit.
Over time, they've reached towards the other side of the sun
and what they're doing is providing us
with a 3-D view of our sun.
It's letting us look at the sun from many different angles,
and instead of just looking at a single image
of a circle that we're seeing
that I've been showing you for most of the time,
this lets us construct a 3-D picture
of where on the surface of the sun
these explosions and flares are happening,
and that's how we can really get the information
to try and estimate if these solar flares
and these coronal mass ejections are going to be directed towards Earth,
if they're going to be directed towards a different planet,
if they're just going to miss Earth entirely.
It really is instrumental to be able
to let us make these predictions.
The center panel might look familiar here.
Before I showed it to highlight
a coronal mass ejection earlier in animated form.
SOHO is another spacecraft that we rely on heavily
for space weather forecasting.
SOHO is the only telescope we have
that's looking from Earth's perspective at the sun
with that disc blocking out and eclipsing the sun
so that we can see the faint corona.
It's a pretty old satellite, actually.
It's about 20 to 25 years old now.
There is a fear among the space weather forecasters
that if that satellite were to break or malfunction,
we really lose our first line of defense.
And we really this need kind of imagery
to be able to measure how fast these events are happening
and how fast the coronal mass ejections are traveling
so we can predict when we'll actually get impacted
if we're going to.
The left and right panel here
are from STEREO-B and STEREO-A,
a very similar setup of the camera,
where you're blocking out the main photosphere of the sun
and just seeing the faint atmosphere around it.
You can see if you kind of step through time
is how you create these movies
of these coronal mass ejections happening.
For each different panel,
the same coronal mass ejections.
You can see that it looks like they're pointed
in different directions in all of them,
and that's because all three of these satellites
are looking at the sun from a different angle.
Just like how our GPS satellites need three satellites
to triangulate a single position here on Earth,
here we have three satellites in space
to triangulate a single event,
a single explosion off the surface of the sun
and triangulate exactly what direction that is headed.
That's what lets us input the information we're seeing
from the corona into our models and make these predictions.
More recently,
you might have heard of the Parker Solar Probe.
This is a very recent satellite
that actually just launched on Sunday,
around 2:00 a.m. on Sunday from Cape Canaveral.
The kind of tagline for this mission
is that it's a mission to touch the sun.
And the reason we say that
is because it's giving us a new view of the corona
by going really close to the sun,
as close as we can really get without getting too close.
It's going to get up to four million miles
from the surface of the sun.
I mean, that sounds like it's not that close.
Are we really lying, saying we're going to touch the sun?
But remember, the atmosphere of the sun,
the corona of the sun, is pretty big, it's faint,
it's hard for us to actually see unless we block out a lot of the light,
and it extends pretty far.
So if we go back to one of these images
where we see one of these coronal mass ejections happening,
four million miles from the surface
is roughly around this red ring.
It still seems like it's pretty far,
but you can see how a coronal mass ejection
is easily very, very close, still at the initial stages
where we're making measurements of it happening
when it would directly come in contact with the satellite.
The Parker Solar Probe is really a groundbreaking mission
to give us insight into what the corona really is
and help us explain why these explosions are happening.
I've told you guys that they happen,
but I haven't really explained why they're happening,
other than just kind of mystically saying the magnetic field is causing them.
Really, the reason I'm doing that is because we don't have
a very good understanding of exactly what's causing them.
The corona is also very, very hot,
much hotter than the surface of the sun
that we can see with visible light.
We don't exactly know why it's as hot as it is,
so this mission is hopefully going to give us
a lot more information to be able to try
and understand and disentangle that information.
Once we have all of this information,
once we can make these measurements
of these coronal mass ejections,
look through them, see how everything is changing,
we can input them into different models.
This is the modeling interface
that NASA actively uses when they make their predictions.
There's a lot going on here,
but the really important things to pay attention to:
the sun is at the center of the image.
Earth is the yellow dots in the different panels.
What you're seeing as time goes by,
this is going through about 10 days' worth of time.
You might see these spiral features
going off of the sun in different directions.
That's being caused by just the ambient solar wind
that we see all the time.
They are often concentrated in these little jets
that correspond with coronal holes or sunspots
that you might be familiar with.
They usually aren't causing too much harm.
They're just kind of always there.
That's why we have these northern lights every night.
Just not very strong.
When a coronal mass ejection happens,
so what's happening, it just went through one.
You might notice a little eruption
happening off the sun there.
That is the input coronal mass ejection
based on the measurements that we can make
from the images we have,
and then it'll travel through the solar system.
This one happens to be directed towards Earth,
and in about two to three days
the model can tell us exactly when we might expect it
to impact us, and the model also has information
on the magnetic fields that are present near Earth,
near the sun, through the coronal mass ejection
when it's happening, and that all combined
is going to give us a prediction of how severe of an impact
we might have here on Earth.
This model feeds into what a lot of people might,
if you subscribe to those northern light alerts
that you can get, or space weather alerts you can get,
they come from the result of primarily this model.
NASA uses this model.
The official space weather broadcasting agency
that the government subscribes to is through NOAA,
the National Oceanic and Atmospheric Administration.
NOAA also uses this model.
One of the cool things about my internship
was that I worked independently of NOAA through NASA,
but we would often collaborate with NOAA,
compare our models, compare our results,
and that way the government has two very independent
sources of information that they can compare
where one set of eyes is doing one type of analysis,
another set of eyes is doing another type of analysis,
and we compare our results and they're usually very, very consistent.
NASA is focusing on internal things,
so keeping sure NASA missions are safe
and the satellites we care about are safe, whereas NOAA is really more concerned
about exactly what's happening on Earth
and keeping infrastructure on Earth
and the government more informed
for political reasons
and also everyday citizens.
And so I'm going to end
with one long, drawn out, slow animation.
It's essentially going to sum up everything I've talked about,
starting all the way from the center of our sun.
What's happening here is it's showing an animation
of how energy is being created in our sun,
and that's through fusion,
so it's when two protons or two hydrogen atoms
collide together, fuse together.
Eventually they'll form helium,
and in that process release a lot of energy.
And that's what's ultimately powering our sun
and providing its energy.
Slowly that energy is going to transport its way
through the sun, make its way to the surface.
Once it reaches closer to the surface,
the magnetic field of the sun will start to interact with it,
and that's when you'll start to have these loopy materials,
these filaments, puffing off of the surface,
heating up the atmosphere, the corona,
and causing from time to time these massive eruptions.
So it's going to walk through a few animations of eruptions,
as well as a few actual real-time movies
that were put together from SDO data.
This is still a computer simulation of the surface.
This is real data.
This is taken from the SDO spacecraft,
looking at parts of the sun and parts of that corona
erupting off because of those magnetic field lines
puffing out and breaking off of the surface.
Keep in mind how big these eruptions are.
Earth, if I were to put a little Earth dot there,
would just be a tiny speck.
And these are happening all of the time.
Here's a particularly massive eruption off the surface.
And now we can actually see as those eruptions
travel through space, they expand,
they get bigger, and they eventually turn
into these really ominous-looking blobs
traveling towards planets in these animations.
So here we have Earth as this pale blue dot,
and this ominous coronal mass ejection
slowly approaching it.
As you look at it from a different angle,
we can start to see how the magnetic field is there,
acting as a shield to redirect a lot of that impact.
But you'll notice once the solar storm approaches,
that magnetic field will start to get compressed.
It will get squeezed inwards a little bit.
You'll see it from a few different angles.
And this is how some of the energy
is going to fall into the poles,
and that energy is what's going to light up
and provide the northern lights.
So as that coronal mass ejection
passes through our magnetic field,
it's compressing the magnetic field
and in that tail end is where you might have
some of these magnetic field lines sparking together,
just like how they release energy on the surface of the sun.
They do the same thing near Earth
and then fall into the poles,
and that's what's energizing atoms in our atmosphere
and lighting up the northern lights
that you can see on both poles.
And that will conclude my talk.
(applause)