WEBVTT

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Welcome to Spotlight. I'm Colin Lauva
and I'm Alice Irazari. Spotlight uses a

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special English method of broadcasting. It
is easier for people to understand no matter

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where in the world they live.
A small craft flies through space. Stars

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shine bright in the darkness. Two
large space rocks or asteroids float in the

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distance. One asteroid slowly circles the
other. The spacecraft, called dark rockets

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towards the smaller asteroid. Dart goes
faster and faster. Soon it is traveling

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at over twenty two thousand kilometers an
hour. It crashes into the side of

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the asteroid. Dart blows apart.
A cloud of dust and metal flies up

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from the asteroid, and slowly this
smaller asteroid begins to change direction. On

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Earth, scientists watch the crash through
the Darts cameras. When the camera stops,

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they cheer, some hug each other. It is the first time humans

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have tried to move a natural object
in space, and it has worked.

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But the crash is much more important
than this experiment. A spacecraft like the

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Dart may one day save the planet
from destruction. Today's Spotlight is on the

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Darts project and the future of planetary
defense. Asteroids are not usually a danger

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to the Earth. Small asteroids enter
the Earth's atmosphere every day. Objects often

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hit the Earth, but they are
not large enough to do any damage or

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These asteroids fall in places where no
one lives. But asteroids come in many

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different sizes. Some are only a
meter across, some are larger than one

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kilometer. If an asteroid this big
were to hit the Earth, it would

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cause a lot of destruction. Eric
Christiansen is a scientist at the Catalina Sky

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Survey. He helps find asteroids and
other objects that could be dangerous. He

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spoke to the University of Arizona News
about these large asteroids. The force of

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an object that size would cause global
problems. It could cause plants and animals

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to die out. It would lift
a lot of dust and water into the

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atmosphere. The effect would be like
a nuclear winter. Less sunlight would reach

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the ground for several years. It
would change the global food supply. Even

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smaller asteroids are dangerous. In nineteen
hundred and eight, an asteroid fell over

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an area in Russia called Tunguska.
Instead of hitting the ground, it's exploded

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in the air. Still, the
asteroid did a lot of damage. It

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destroyed over two thousand square kilometers of
forest. Scientists suggest the explosion was as

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powerful as the biggest nuclear bombs ever
tested. Chuchen was a member of the

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Shanyagear tribe. He was in the
woods when the Tunguska asteroid fell. He

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spoke to I Am Souslav about his
experiences. The earth began to move and

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shake. The wind hit our house
and pushed it over. My body was

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pushed down by sticks, but my
head was fine. Then I saw a

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wonder. Trees were falling, the
branches were on fire. It became very

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bright. How can I say this? It was as if there were a

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second sun. My eyes were hurting. I even closed them. It was

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like what the Russians call lightning.
This explosion is known as the Tunguska event.

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It is the biggest asteroid to hit
the Earth in recent history, but

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the Tunguska asteroid was not extremely big. Scientists believe it was about sixty five

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meters across. Even events like Tunguska
do not happen very often, but it

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is important to protect against them.
Over the years, scientists have mapped many

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of the large asteroids. They know
where they are and they can guess where

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they are going, But scientists did
not know if they could change where an

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asteroid fell. They did not know
the best way to do it. One

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method scientists have discovered is called kinetic
impact. A kinetic impact would mean pushing

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an asteroid. Scientists would not have
to push its month. A small push

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in the right direction could make an
asteroid avoid Earth. The DART project was

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the world's first try at kinetic impact. It did not target an asteroid coming

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toward Earth. Instead, DART was
a test. In fact, the name

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DART itself stands for double Asteroid Redirection
Test. The rocket would fly toward a

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large asteroid called Didymus. Once it
came close, it would fly toward a

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smaller asteroid called Dimorphous. Dimorphous circle
or orbits around Didymus. It is the

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same way the Moon orbits the Earth. Then DART would crash into Dimorphous.

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Scientists hoped the crash would move the
asteroid they wanted to shorten its orbit.

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By studying the orbit, they could
see how much force DART had. Then

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they could use that information when trying
to push asteroids in the future. Ed

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lu Is, the director of the
Asteroid Institute, It is an organization that

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focuses on planetary defense. He spoke
to news organization NPR about the DARTS project's

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success. The point is this is
a great thing. Someday we are going

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to find an asteroid which has a
high chance of hitting the Earth. We

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are going to want to avoid it. We should have some experience first,

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we should know that this would work. DART was a project started by NASA,

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or the National Aeronautics and Space Administration. The United States provides the money

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for this government agency, but many
other countries came together to make the project

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possible. The Japanese Airspace Exploration Agency
helped, the Italian Space Agency helped monitor

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DART. In several years, the
European Space Agency will send a ship to

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Dimorphous. They will study what changes
DART made to the asteroid. Defending the

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planet is important. Asteroids are not
an immediate danger to Earth, but in

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a hundred years we may need this
technology. But planetary defense is a very

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large job. It requires many countries
to work together. Bill Nelson is the

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NASA administrator. He spoke in a
press release after the DART test. As

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a whole, DART represents a great
success for planetary defense. But it is

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also a project of coming together.
It helps all humanity. NASA studies space

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and our home planet, but we
are also working to protect that home.

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This involved many countries working together.
It turned made up science fiction stories into

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science facts, and it demonstrated one
way to protect Earth. Have you heard

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of the Dart project? Do you
think it is important? What else could

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people do to protect the Earth?
You can and leave a comment on our

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website or email us at Radio at
Radio English dot net. You can also

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comment on Facebook at Facebook dot com
slash Spotlight Radio. You can also get

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our programs delivered directly to your Android
or Apple device through our free official Spotlight

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English app. The writer of this
program was Dan Christman. The producer was

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Michio Ozaki. The voices you heard
were from the United Kingdom and the United

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States. All quotes were adapted for
this program and voiced by Spotlight. You

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can listen to this program again and
read it on the internet at www dot

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Radio English dot net. This program
is called dot We hope you can join

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us again for the next Spotlight program. Goodbye,