I was having sort of a difficult year that year

because people had this idea of the Mayan apocalypse.

We kept telling people that there was really no reason

to worry about anything.

There was nothing unusual astronomically happening.

Of course, (laughs) what almost happened

would have been really bad for me to deal with.

The sun was in a naturally active period that year.

Every 11 years or so, the sun becomes very active,

and then it gets quieter again.

But 2012 and 2013 were the peak of this natural cycle.

And so what happened actually is that

there was a colossal coronal mass ejection.

The thing, though, is it went off

on the other side of the sun from the earth.

And we had satellites out there in that other direction,

out in the solar system.

And they got knocked silly by this big burst

of charged particles from the sun.

And so we looked at that, and we were able to observe it

and see what had happened and track it and all of that.

We all kind of went, "whew." (laughs)

The source of these high-energy particles

and exactly how they get accelerated away from the sun

is what we're studying right now.

When I say high-energy particles,

I'm talking electrons and protons

and sometimes as large as the nucleus of a helium atom,

something like that.

And they get blasted through our solar system

at a million miles an hour in some cases.

And so we have this very high-energy wind.

It changes planets.

It's responsible for Mars losing its atmosphere over time

and becoming this cold, dead desert.

It's responsible for Venus becoming

this hellish thing that we know it.

It actually blasted away all of the lighter molecules,

like water, and it left Venus with an atmosphere

of carbon dioxide and sulfuric acid

and, ugh, yeah, really bad stuff.

The only reason the earth is not really affected by it much

is because we have a very strong magnetic field.

And so our molten metal core,

all that molten metal moving around inside the earth

generates a magnetic bottle around the earth.

And that protects us from the solar wind.

But someday, the sun will actually

pretty much blast away our atmosphere.

So planets change.

We have this early warning system

to see if there's something dangerous coming from the sun.

And we would have probably about a day's notice

as one of these big storms made its way through the sun.

The sun we think of as putting off lots of light,

and light travels at the speed of light,

which takes about eight minutes to get from the sun to us.

But this isn't light.

These are charged particles, protons and electrons.

And although they may be moving millions of miles an hour,

it still will take them about a day or more

to get to the earth.

So we will have some warning.

The solar wind normally

doesn't really have much danger to us

or the environment in space.

But just like weather implies,

when you're dealing with space weather,

sometimes there's a really big line

of thunderstorms coming through.

So in the case of the sun,

the sun sometimes has very, very violent storms.

And these are storms caused

by the chaotic, twisting magnetic field of the sun.

Some of the hot gas on the surface of the sun

actually gets accelerated so quickly

by these magnetic fields

that it just breaks off and takes off into space.

And in one moment, you could have trillions of tons

of fast, high-moving, charged material

coming out towards the Earth.

Now, that's not actually very dangerous to us biologically,

but what that can do is carry a huge amount

of electrical and magnetic energy.

All of a sudden, all these charged particles

hit the magnetic field of the Earth.

And it can actually dump electric current

right into our magnetic field.

In the case of all of our satellites

up above the atmosphere, they're very at risk.

So we can basically shut them down,

put them to sleep for a little while.

And of course, that energy burst will hit them,

and it may damage their detectors,

but at least most of the electronics are shut down

at the time, and we can recover them, hopefully.

And then there may even be plans

that are necessary to shut down parts of power grids

because I think the biggest danger of these things to us

is that when they actually hit the Earth's field,

you can have so much, again,

energy in that magnetic field of the earth

that it could fry our power grids.

Think about how bad it would be if all the power on earth

just went out because of one of these solar storms.

That could conceivably cause billions

or maybe even trillions of dollars of damage.

So there are people rehearsing these scenarios.

There are people trying to figure out

how we would shut things down,

how we would protect ourselves.

And then we have our fleet of satellites

trying to observe the sun all the time.

But yes, all around you,

there are people monitoring space weather

and getting ready for a big storm.

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