WEBVTT

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

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

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

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Stars shine bright in the darkness.
Two large space rocks or asteroids, floats

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

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Dart, rockets towards the smaller asteroid. Dart goes faster and faster. Soon

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it is traveling at over twenty two
two thousand kilometers an hour. It crashes

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into the side of the asteroid.
Dart blows apart. A cloud of dust

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and metal flies up from the asteroid, and slowly this smaller asteroid begins to

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change direction. On Earth, scientists
watch the crash through the Dart's cameras.

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When the camera stops, they cheer, some hug each other. It is

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the first time humans have tried to
move a natural object in space, and

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it has worked. But the crash
is much more important than this experiment.

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A spacecraft like the Dart may one
day save the planet from destruction. Today's

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spotlight is on the Dart Project and
the future of planetary defense. Asteroids are

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not usually a danger to the Earth. Small asteroids enter the Earth's atmosphere every

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day. Objects often hit the Earth, but they are not large enough to

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do any damage. Or These asteroids
fall in places where no one lives.

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But asteroids come in many different sizes. Some are only a meter across,

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some are larger than one kilometer.
If an asteroid this big were to hit

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the Earth, it would cause a
lot of destruction. Eric Christiansen is a

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scientist at the Catalina Sky Survey.
He helps find asteroids and other objects that

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could be dangerous. He spoke to
the University of Arizona News about these large

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asteroids. The force of an object
that size would cause global problem. It

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could cause plants and animals to die
out. It would lift a lot of

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dust and water into the atmosphere.
The effect would be like a nuclear winter.

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Less sunlight would reach the ground for
several years. It would change the

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global food supply. Even smaller asteroids
are dangerous. In nineteen hundred and eight,

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an asteroid fell over an area in
Russia called Tunguska. Instead of hitting

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the ground, it exploded in the
air. Still, the asteroid did a

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lot of damage. It destroyed over
two thousand square kilometers of forest. Scientists

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suggest the explosion was as powerful as
the biggest nuclear bombs ever tested. Chuchen

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was a member of the Shania Gear
tribe, was in the woods when the

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Tunguska asteroid fell. He spoke to
I Am Souslav about his experiences. The

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earth began to move and shake.
The wind hit our house and pushed it

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over. My body was pushed down
by sticks, but my head was fine.

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Then I saw a wonder. Trees
were falling, the branches were on

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fire. It became very bright.
How can I say this? It was

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as if there were a second son. My eyes were hurting. I even

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closed them. It was like what
the Russians call lightning. This explosion is

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known as the Tunguska event. It
is the biggest asteroid to hit the Earth

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in recent history, but the Tunguska
asteroid was not extremely big. Scientists believe

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it was a about sixty five meters
across. Even events like Tunguska do not

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happen very often, but it is
important to protect against them. Over the

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years, scientists have mapped many of
the large asteroids they know where they are

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and they can guess where they are
going. But scientists did not know if

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they could change where an asteroid fell. They did not know the best way

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to do it. One method scientists
have discovered is called kinetic impact. A

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kinetic impact would mean pushing an asteroid. Scientists would not have to push it

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much. A small push in the
right direction could make an asteroid avoid Earth.

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The Dirt Project was the world's first
try at kinetic impact. It did

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not target an asteroid coming toward Earth. Instead, DART was a test.

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In fact, the name DART itself
stands for double Asteroid Redirection Test. The

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

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it would fly toward a smaller asteroid
called Dimorphous. Dimorphous circles or orbits around

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Didymus. It is the same way
the Moon orbits the Earth. Then DART

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would crash into Dimorphous. Scientists hope
that crash would move the asteroid. They

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wanted to shorten its orbit. By
studying the orbit, they could see how

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much force DART had. Then they
could use that information when trying to push

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asteroids in the future. Ed lu
Is, the director of the Asteroid Institute.

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It is an organization that focuses on
planetary defense. He spoke to news

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organization NPR about the darts Jek's success. The point is this is a great

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thing. Someday we are going to
find an asteroid which has a high chance

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of hitting the Earth. We are
going to want to avoid it. We

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should have some experience first, we
should know that this would work. DART

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was a project started by NASA,
or the National Aeronautics and Space Administration.

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The United States provides the money for
this government agency, but many other countries

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came together to make the project possible. The Japanese Aerospace Exploration Agency helped,

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the Italian Space Agency helped monitor DART. In several years, the European Space

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Agency will send a ship to Dimorphus. They will study what changes DART made

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to the asteroid. Defending the planet
is important. Asteroids are not an immediate

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danger to Earth, but in a
hundred years we may need this technology.

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But planetary defense is a very large
job. It requires many countries to work

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together. Bill Nelson is the NASA
administrator. He spoke in a press release

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after the DART test. As a
whole, DART represents a great success for

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planetary defense, but it is also
a project of coming together. It helps

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all humanity. NASA studies space and
our home planet, but we are also

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working to protect that home. This
involved many countries working together. It turned

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made up science fiction stories into science
facts, and it demonstrated one way to

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protect Earth. Have you heard of
the Dart project? Do you think it

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is important? What else could people
do to protect the Earth? You can

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leave a comment on our website or
email us at Radio at Radio English dot

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

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The writer of this program was Dan
Christman. The producer was Michio Ozaki.

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The voices you heard were from the
United Kingdom and the United States.

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

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to this program again and read it
on the internet at www dot Radio English

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dot net. This program is called
Dart. You can also get our programs

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delivered directly to your Android or Apple
device through our free official Spotlight English app.

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We hope you can join us again
for the next Spotlight program. Goodbye, m