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Hi, I'm John and this is
NASA Now for January 4, 2012.
Lately we have been
hearing a lot of talk
about solar storms
and solar flares.
So what's happening with our
sun and how does it affect us?
We'll find out later
in the program.
But first, here's what's
happening at NASA Now.
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Last year, NASA's Solar Dynamics
Observatory, commonly known
as SDO, provided stunning images
of major activity on the sun.
The images showed a
massive region on the sun
that scientists call
the benevolent monster.
This area is one of the most
active regions on the sun
and it produced huge
solar flares.
A solar flare is a burst
of electromagnetic energy
from the sun that
has the potential
to disrupt communications
and electrical systems
here on Earth.
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Ah, the sun!
It is a source of
life on our planet.
It can also provide a
bombardment of charged particles
and electromagnetic radiation
that has the capacity
to disrupt telecommunications
and power grids.
Here to dispel some
misconceptions
and give us a much
better understanding
of the sun is astrophysicist
Mitzi Adams
at the Marshall Space
Flight Center.
Hello Mitzi, how would
you describe our sun?
The sun is a star.
It's actually a middle-aged
star.
It's made of hydrogen and
a little bit of helium
and some other trace elements.
It's all gas, but it's gas
that's at a very special state
and it's gas that's
actually producing energy.
What fuels the sun?
In the interior of the sun,
energy is produce
by nuclear fusion.
This process takes part
of a hydrogen atom,
which is a proton, and fuses
another hydrogen atom together.
Does the sun have different
layers just like our own planet?
The sun has an interior
and the very middle
of the sun is called the core.
The core produces energy
from nuclear fusion.
Outside the core you have
a couple of more layers.
You have the radiative zone,
then you have the convective
zone and at that point,
you've reached what we call
the surface and we call
that layer the photosphere.
The chromosphere is above
that and the corona,
the crown of the
sun, is above that.
And in the photosphere,
we see sunspots.
In the chromosphere,
we can see prominences
and we can see flares and then
in the corona we see
coronal mass ejections.
You mentioned coronal mass
ejections, can you explain?
Coronal mass ejections are
associated with solar flares
and this is when material
actually escapes the
gravitational field of
the sun and is propelled
out into interplanetary space.
And this material, which is
made up of protons, electrons,
is traveling at very
high rates of speed.
And if that coronal mass
ejection is pointed towards the
Earth, we can have aurora,
we can have problems
with our GPS systems,
we can have problems
with airplanes needing to reduce
the altitude in which they fly.
Astronauts are asked not to
go outside the space station
and sometimes actual
satellites can be impacted.
Are coronal mass injections
connected to the solar cycle?
The sun has spots.
The spots disappear and
appear in a cycle of activity
that spans 11 years from minimum
to minimum or maximum to maximum
and so we are currently
coming out of the minimum
and we are moving into a
region on a graph that looks
like we're kind of
climbing a hill.
And at the top of that hill
is what we call the maximum
of the sunspots cycle.
During the maximum there
are many, many spots
and these spots are associated
with a magnetic field.
The magnetic field
can become twisted up,
kind of like a rubber band,
and when you get enough energy
in that rubber band it
will snap or it can snap.
That's called a solar flare.
How can we track what's
going on with the sun?
You can actually look at
spaceweather.com to find
out when this is
going to happen.
There are also space
weather alerts.
So that if you want to know
when a coronal mass
ejection has occurred
and will be directed
towards us, you'd be alerted
that it is happening and aurora
might even be going on too.
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Our expert has created
an activity just for you.
Check it out.
You and your classmates will
use actual images of the sun
to determine the number of
sunspots and their size.
Go the NASA Explorer
Schools Virtual Campus
and see what you can
find out about our sun.
Well that's it for NASA
Now, be sure to check
out our Facebook page.
See you then on NASA Now.
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NASA Now comes to you
from the Virtual Campus
at NASA Explorer Schools.
