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Well this is something that
really is a once-in-a-lifetime event for so many people. The Earth, the moon and the sun
are going to line up perfectly so that the moon actually blocks out the sun
that casts a shadow down on the Earth. And there's about a 70 mile path
that's going to go all the way across the United States. It's going to start in Portland, Oregon and actually end
in Charleston, South Carolina. And in that one little strip the sky
will go entirely dark. The moon will entirely cover up the sun.
But even if you're not in that strip you're going to see something called a partial solar eclipse.
So different levels of the sun will be blocked depending on where you are in the United States.
But everyone in the United States has a chance to view this and participate
in this wonderful natural event.
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Well if you're lucky enough to actually be in the path of totality, it's something that changes
your life. I've seen two total eclipses of the sun. And
the dark goes entirely dark, the moon covers up the sun and you're able to see
something called the solar corona which is the atmosphere of the sun. So you see these streaming
streamers of light coming away from the covered up sun. And that you can actually
see with your unaided eye. You can take off any sort of eye projection when it's totally
dark and look up at the sky. You see the stars come out. You see the planets Mercury
and Venus near the sun. And you actually see a 360 degree
sunset all the way around you. If you're not in the path of totality,
there really important thing is to get some good eye projection. So there are eclipse
glasses and you can actually find out where to get these and how to use them properly
on our website. NASA's put together a big website called eclipse2017.nasa.gov
And you can go there to find out how much
of the sun is going to be blocked out in your area. Where to get eclipse glasses
and also other ways to view the eclipse safely.
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Well the main thing that I really can't iterate enough is that
even a tiny little bit of the sun is still visible it can damage your eyes.
So unless the moon is entirely covering up the sun you either need
eclipse viewing glasses or you can do something relatively simple called a pinhole
camera. And with a pinhole camera all you need to do is punch a little hole
in a piece of cardboard or you can actually use something like a colander. You know a kitchen
implement that has little holes in it. You let the sunlight shine through that
and then you look down on the ground at the image that's being projected
Those little holes will actually focus the sunlight and you'll be able to see
a crescent shape. You'll be able to see the moon blocking out a good portion of the sun.
But do not ever look at the sun even if a little bit of the surface is uncovered.
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If even a little bit of the sun is not
blocked then the sky will be mainly bright, but you'll notice changes
There will be changes in the temperature. You'll be able to actually want animals change.
Birds will go back to their nests if it gets quite dark. You know one of the amazing
things is you can help us take information about this. NASA is going taking information
about changes in temperature, changes in cloud shapes. We have an app
called the GLOBE Observer. And if you just have a simple cheap thermometer
If you download this app, you can enter data about how the temperature is changing
and how clouds are changing and we're going to use that to do original science
research about how sunlight and the Earth's atmosphere interact.
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All of the energy that we use on this planet originally comes from the sun
and it may surprise you to know that something as simple as sunlight
is not perfectly understood. Our atmosphere absorbs sunlight
it reflects some. There are different levels of the atmosphere, different colors that are used.
So we actually have experiments set up to figure out how much sunlight actually reaches
the surface of the Earth. And we have an experiment going to the space station later this year
called TSIS which is going to measure the total amount of sunlight that the Earth receives.