Welcome to Spotlight Advanced. I'm Colin Lauva and I'm Alice Irasari. Spotlight uses
a special English method of broadcasting. It is easier for people to understand no
matter where in the world they live. A small craft flies through space.
Stars shine bright in the darkness. Two large space rocks or asteroids float in
the distance. One asteroid slowly circles the other. The spacecraft, called Dart,
rockets towards the smaller asteroid. Dart goes faster and faster. Soon it
is traveling at over twenty two two thousand kilometers an hour. It crashes into
the side of the asteroid. Dart blows apart. A cloud of dust and
metal flies up from the asteroid, and slowly this smaller asteroid begins to change
direction. On Earth, scientists watch the crash through the Darts cameras. When
the camera stops, they cheer, some hug each other. It is the
first time humans have tried to move a natural object in space, and it
has worked. But the crash is much more important than this experiment. A
spacecraft like the Dart may one day save the planet from destruction. Today's Spotlight
is on the Dart project and the future of planetary defense. Asteroids are not
usually a danger to the Earth. Small asteroids enter the Earth's atmosphere every day.
Objects often hit the Earth, but they are not large enough to do
any damage. Or These asteroids fall in places where no one lives. But
asteroids come in many different sizes. Some are only a meter across, some
are larger than one kilometer. If an asteroid this big were to hit the
Earth, it would cause a lot of destruction. Eric Christiansen is a scientist
at the Catalina Sky Survey. He helps find asteroids and other objects that could
be dangerous. He spoke to the University of Arizona News about these large asteroids.
The force of an object that size would cause global problems. It could
cause plants and animals to die out. It would lift a lot of dust
and water into the atmosphere. The effect would be like a nuclear winter.
Less sunlight would reach the ground for several years. It would change the global
food supply. Even smaller asteroids are dangerous. In nineteen hundred and eight,
an asteroid fell over an area in Russia called Tunguska. Instead of hitting the
ground, it exploded in the air. Still, the asteroid did a lot
of damage. It destroyed over two thousand square kilometers of forest. Scientists suggest
the explosion was as powerful as the biggest nuclear bombs ever tested. Cheuten was
a member of the Shanyagear tribe, was in the woods when the Tunguska asteroid
fell. He spoke to I Am Souslav about his experiences. The earth began
to move and shake. The wind hit our house and pushed it over.
My body was pushed down by sticks, but my head was fine. Then
I saw a wonder. Trees were falling, the branches were on fire.
It became very bright. How can I say this? It was as if
there were a second sun. My eyes were hurting. I even closed them.
It was like what the Russians call lightning. This explosion is known as
the Tunguska event. It is the biggest asteroid to hit the Earth in recent
history, but the Tunguska asteroid was not extremely big. Scientists believe it was
a sixty five meters across. Even events like Tunguska do not happen very often,
but it is important to protect against them. Over the years, scientists
have mapped many of the large asteroids. They know where they are and they
can guess where they are going, But scientists did not know if they could
change where an asteroid fell. They did not know the best way to do
it. One method scientists have discovered is called kinetic impact. A kinetic impact
would mean pushing an asteroid. Scientists would not have to push it much.
A small push in the right direction could make an asteroid avoid Earth. The
Dirt Project was the world's first try at kinetic impact. It did not target
an asteroid coming toward Earth. Instead, Dirt was a test. In fact,
the name DART itself stands for double Asteroid Redirection Test. The rocket would
fly toward a large asteroid called Didymis. Once it came close, it would
fly toward a smaller asteroid called Dimorphos. Dimorphous circles or orbits around Didamis.
It is the same way the Moon orbits the Earth. Then DART would crash
into Dimorphos. Scientists hope the crash would move the asteroid. They wanted to
shorten its orbit. By studying the orbit, they could see how much force
DART had. Then they could use that information when trying to push asteroids in
the future. Ed lou Is, the director of the Asteroid Institute. It
is an organization that focuses on planetary defense. He spoke to news organization NPR
about the Dart prices success. The point is this is a great thing.
Someday we are going to find an asteroid which has a high chance of hitting
the Earth. We are going to want to avoid it. We should have
some experience first, we should know that this would look. DART was a
project started by NASA, or the National Aeronautics and Space Administration. The United
States provides the money for this government agency, but many other countries came together
to make the project possible. The Japanese Aerospace Exploration Agency helped, the Italian
Space Agency helped monitor DART. In several years, the European Space Agency will
send a ship to Dimorphos. They will study what changes DART made to the
asteroid. Defending the planet is important. Asteroids are not an immediate danger to
Earth, but in a one hundred years we may need this technology. But
planetary defense is a very large job. It requires many countries to work together.
Bill Nelson is the NASA administrator. He spoke in a press release after
the DART test. As a whole, DART represents a great success for planetary
defense, but it is also a project of coming together. It helps all
humanity. NASA studies space and our home planet, but we are also working
to protect that home. This involved many countries working together. It turned made
up science fiction stories into science facts, and it demonstrated one way to protect
Earth. Heard of the Dirt Project? Do you think it is important?
What else could people do to protect the Earth? You can leave a comment
on our website or email us at Radio at Radio English dot net. You
can also comment on Facebook at Facebook dot com slash Spotlight Radio. The writer
of this program was Dan Christman. The producer was Michyo Ozaki. The voices
you heard were from the United Kingdom and the United States. All quotes were
adapted for this program and voiced by Spotlight. You can listen to this program
again and read it on the internet at www dot Radio English dot net.
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can join us again for the next Spotlight program. Goodbye,