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DART (Advanced Program) · Spotlight English: Advanced

• 0:02
  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