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International Asteroid Day | DART (Advanced Program) · Spotlight English: Advanced

• 0:02
  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
• 9:15
  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,