In recognition of the UN’s “International Week of Science and Peace”, Colin Lowther and Alice Irrizary talk about the DART project and how scientists are working on a future planetary defense system.

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Welcome to Spotlight. I’m Colin Lowther.

Click here to follow along with this program on YouTube.

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And I’m Alice Irrizary. Spotlight uses a special English method of broadcasting. It is easier for people to understand, no matter where in the world they live.

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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 toward the smaller asteroid.  DART goes faster and faster. Soon it is traveling at over twenty-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.  

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On earth, scientists watch the crash through the DART’s 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.

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Today’s Spotlight is on the DART project and the future of planetary defense.

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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.

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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.

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Eric Christensen 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:

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“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.”

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Even smaller asteroids are dangerous. In 1908 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 2000 square kilometers of forest. Scientists suggest the explosion was as powerful as the biggest nuclear bombs ever tested.

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Chuchan was a member of the Shanyagir tribe. He was in the woods when the Tunguska asteroid fell. He spoke to I. M. Suslov about his experiences:

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“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.“

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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 about 65 meters across.

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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.

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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.

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The DART project was the world’s first try at kinetic impact. It did not target an asteroid coming toward Earth.  Instead, DART was a test. In fact, the name DART itself stands for Double Asteroid Redirection Test. The rocket would fly toward a large asteroid, called Didymos. Once it came close, it would fly toward a smaller asteroid, called Dimorphos. Dimorphos circles, or orbits, around Didymos. It is the same way the moon orbits the earth. Then, DART would crash into Dimorphos. Scientists hoped 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.

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Ed Lu 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 project’s success:

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“The point is, this is a great thing. Some day, 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 work.”

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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.

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Defending the planet is important. Asteroids are not an immediate danger to Earth. But in a 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:

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“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.”

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Have you heard of the DART 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 You can also comment on Facebook at

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The writer of this program was Dan Christmann. The producer was Michio 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 This program is called, ‘DART’.

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You can also get our programs delivered directly to your Android or Apple device through our free official Spotlight English app. We hope you can join us again for the next Spotlight program.



Have you heard of the DART project?  Do you think Planetary defense is important? What else could people do to protect the earth from an asteroid?

Join the discussion

  • I have always thought that if the ancient Greeks, who lived 2500 years ago, could return to earth, seeing current technological inventions that cancel distances and increase man’s capabilities, they would believe they had arrived in the Olympus of the gods. Now that technological development has become very accelerated, from the industrial revolution of a couple of centuries ago, to today’s artificial intelligence, we cannot even imagine what the world will be like in 100 or 1000 years. This week’s Spotlight program made me think of a cosmic ball game. Seeing an asteroid approaching, the inhabitants of a planet hit it to deflect it. The inhabitants of another planet, seeing him coming to their area, hit him in turn to remove him from their planet and the game continues. P.S. I apologize for the stupid things.

  • I think this project is very important for our live in the future, because it will help us to avoid a dangerous asteroids or objects that will destroy our planet or any country.
    But it is a hard thing to do But I think it’s not difficult for our scientists.
    Thank you spotlight for this amazing Subject.
    And thanks for our scientists For their effort

  • No, I have not heard of DART proyect.
    Yes i think that planetary defense is important so we can avoid asteroids of hitting the planet.
    I think they could do a giant laser that hits the asteroid making it explote.

  • Yes, in my perspective I think the planetary defense is important.
    We can use the artificial intelligence , it’s indensipinsple in our lives, I think that can help researchers to find new solutions to protect the earth from an asteroid

  • Yes, I’m familiar with the DART (Double Asteroid Redirection Test) project. It’s a NASA mission designed to test asteroid deflection technology by deliberately crashing a spacecraft into a small moonlet of a binary asteroid system.

  • i didnt have any Information of the DART project, i thinking Planetary defense is important, To confront it and protect us from it through technological development.

  • To be honest, I haven’t heard of the DART Project, but when I listened to this podcast and read the transcript, I understood what the DART Project meant.

  • I heard about DART (Double Asteroid Redirection Test ) in Vietnamese 2 years ago. It’s better find and destroy big asteroids in space far away from the earth. The Planetary defense is very important for all of us. We must read, listen to and know more about it in our lifetime.

  • I think the humanity must come forward an tahts great
    ..but also some times it’s better to dont know every thing..i mean this is madness ..we took about change thing in the university and that’s have serious consequences.. we need to let these things to the god because in the end we all will a die

  • No , I am not heard of the DART project .
    Yes, sure this subject is important.
    Yes, people can protect the earth from an asteroid ☄️
    To invent something like iron dome to protect the country from rokects and to work the same idea , but in space

  • I want to see thanks spotlight on this topic it is good to acquire new knowledge, Furthermore helps me learn new vocabulary.

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