WEBVTT

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Welcome to Spotlight Advanced. I'm Colin
Lauva and I'm Alice Irasari. 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 float in

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

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

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

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

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

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direction. On Earth, scientists watch
the crash through the Darts cameras. When

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

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

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

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

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is on the Dart project and the
future of planetary defense. Asteroids are not

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usually a danger to the Earth.
Small asteroids enter the Earth's atmosphere every day.

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

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

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

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

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

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

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

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The force of an object that size
would cause global problems. It could

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

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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 global

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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 the

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

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

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the explosion was as powerful as the
biggest nuclear bombs ever tested. Cheuten was

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a member of the Shanyagear tribe,
was in the woods when the Tunguska asteroid

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fell. He spoke to I Am
Souslav about his experiences. The earth began

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

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

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

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

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there were a second sun. My
eyes were hurting. I even closed them.

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It was like what the Russians call
lightning. This explosion is known as

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the Tunguska event. It is the
biggest asteroid to hit the Earth in recent

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

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a sixty five meters across. Even
events like Tunguska do not happen very often,

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but it is important to protect against
them. Over the years, scientists

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have mapped many of the large asteroids. They know where they are and they

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can guess where they are going,
But scientists did not know if they could

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change where an asteroid fell. They
did not know the best way to do

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

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

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

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Dirt Project was the world's first try
at kinetic impact. It did not target

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an asteroid coming toward Earth. Instead, Dirt was a test. In fact,

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the name DART itself stands for double
Asteroid Redirection Test. The rocket would

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

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fly toward a smaller asteroid called Dimorphos. Dimorphous circles or orbits around Didamis.

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It is the same way the Moon
orbits the Earth. Then DART would crash

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into Dimorphos. Scientists hope the crash
would move the asteroid. They wanted to

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shorten its orbit. By studying the
orbit, they could see how much force

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DART had. Then they could use
that information when trying to push asteroids in

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the future. Ed lou Is,
the director of the Asteroid Institute. It

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

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about the Dart prices success. The
point is this is a great thing.

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Someday we are going to find an
asteroid which has a high chance of hitting

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the Earth. We are going to
want to avoid it. We should have

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some experience first, we should know
that this would look. DART was a

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project started by NASA, or the
National Aeronautics and Space Administration. The United

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States provides the money for this government
agency, but many other countries came together

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

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

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send a ship to Dimorphos. They
will study what changes DART made to the

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

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Earth, but in a one hundred
years we may need this technology. But

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

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

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

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

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

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

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

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Earth. Heard of the Dirt Project? Do you think it is important?

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What else could people do to protect
the Earth? You can leave a comment

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on our website or email us at
Radio at Radio English dot net. You

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can also comment on Facebook at Facebook
dot com slash Spotlight Radio. The writer

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of this program was Dan Christman.
The producer was Michyo Ozaki. The voices

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you heard were from the United Kingdom
and the United States. All quotes were

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adapted for this program and voiced by
Spotlight. You can listen to this program

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again and read it on the internet
at www dot Radio English dot net.

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This program is called dot You can
also get our programs delivered directly to your

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Android or Apple device through our free
official Spotlight English app. We hope you

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can join us again for the next
Spotlight program. Goodbye,