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Passage(文章后设5道题,考生需在理解文章的基础上从每个问题提供的4个选项A、B、C、D中选出1个最佳答案。) Mission managers at NASA spent $330 million to send a refrigerator-size craft 7 million miles into space and punch an asteroid(小行星)in the nose. The spacecraft is known as DART, which stands for Double Asteroid Redirection Test. It was launched last November. Its job was to fly out to the asteroid Dimorphos and crash into it. The purpose of the collision(碰撞)was to see if DART impact could speed up the asteroid's orbit around another space rock, Didymos. Neither Dimorphosnor Didymos poses(姿势)any danger to Earth. But in the future, other asteroids might. The DART's impact tested a technology that could one day be needed to protect our planet. The collision took place on September 26. Dimorphos completes an orbit around Didymos every11 hours and 55 minutes. For the mission to be a success, NASA calculated that DART would have to change Dimorphos's orbit by at least 73 seconds. On October 11, the DART team announced its results: The collision sped up Dimorphos's orbit by 32 minutes. Ever since the collision, six Earth-based telescopes have kept watch on Dimorphos. They are capturing images not just of the asteroid but of the rock and dust that DART's impact blasted(枯萎的)into space. It's too soon to know exactly what the DART results mean for the future of planetary defense. But it has now been proven that it's possible to change the speed of an asteroid, and that's a good start. While there are currently no asteroids on a direct impact course with Earth, there is a large【缺少答案,请补充】
Passage(文章后设5道题,考生需在理解文章的基础上从每个问题提供的4个选项A、B、C、D中选出1个最佳答案。) The nuclear power emergency at a Japanese atomic power plant last March could lead to a major re - examination in European countries that are already building such plants or are considering a shift from fossil(化石) fuels to nuclear energy to fight climate change. With the terrible accident 25 years ago in Chernobyl(切尔诺贝利) beginning to fade in European memories, governments across Europe have grown more open to using more nuclear power. Enthusiasm for nuclear power is particularly strong in Eastern Europe, which wants to move away from dependence on Russian oil and natural gas, and on heavily polluting coal - fired power plants. Eastern governments have begun improving existing nuclear plants or are building or planning new ones. But as Japan struggled to deal with its nuclear crises, discussion about the good and the bad of nuclear power became heated. In Germany, nuclear power has been a repeatedly argued and widely felt issue for decades. Up to 70 percent of Germans oppose nuclear power. Recently about 40, 000 people turned out to form a human chain near a nuclear plant to protest government policies on nuclear power. "The accident in Japan could lead to a major rethink in Europe," said Henrik Paulitz of the International Doctors for the Prevention of Nuclear War. "Governments have not been quite open about the safety levels of the nuclear power plants." Chancellor(总理) Angela Merkel heads a center - right unity government that supports the use of nuclear power. Her government recently made a disputed decision to extend the life of the country's 17 nuclear power plants by an average of 12 years. She will now face more pressure to change that policy. She called an emergency meeting with her senior ministers. "We know how safe our plants are and that we do not face a threat from such a serious earthquake or violent tidal wave," Mrs. Merkel said after the meeting. "We will learn what we can from the events in Japan, but (此处原文可能有遗漏)【缺少答案,请补充】