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An international team of astronomers has discovered 11 new planets outside the solar system, raising fresh speculation about the possibility of life in outer space. Astrophysicists from the Geneva Observatory and the European Southern Observatory (ESO) headquartered in Germany, were involved in the detections announced earlier this month. Since the first extrasolar planet was found orbitting around the star 51 Pegasi in 1995, astronomers have pinpointed between 60 and 70 such heavenly bodies across the universe. Each discovery raises new questions about the formation and behaviour of planets among scientists raised on the assumption that distant planets orbitted stars the way the Earth and other planets in the solar system revolve around the sun. But astronomers are now detecting planets of unexpected size in areas where they least expected to find them. Last year, they found a handful of new planets similar in size to small stars and others that moved freely in space without orbitting any star. Some of the 11 planets whose discovery has just been disclosed have special characteristics, according to the ESO. One of them is a gas giant at least 5. 6 times as massive as Jupiter, the largest planet in the solar system. It was detected around a star known under the scientific designation HD28185. Many of the previously discovered extrasolar planets of similar size were found close to stars or revolved around them in eccentric orbits. But the new one has an almost circular orbit similar to that of our own planet. Its orbital period of 385 days is also similar to the year taken by the Earth to travel around the sun. Its average distance from its central star is 150. 6 million kilometres, almost the same as the 149. 6 million kilometres between our planet and the sun. This would place the new planet in a so-called hospitable zonewhere temperatures similar to those on Earth are possible. Although such gas giants are not considered favorable to the development of life forms, they could have moons around them where life might be theoretically possible. Another new discovery is a two-planet system around the star HD82943 where the orbit of one of the planets is twice as long as that of the other. Such commensurable orbits also exist in the solar system. A further two-planet system was detected near the star HD74156, with one of the planets similar to the mass of Jupiter and the other having a far greater mass. Another new discovery was a giant planet 3. 4 times the mass of Jupiter that approached to within 5 million kilometres of the star HD80606. At its furthest point it was 127 million kilometres away. In contrast Mercury, the planet nearest the sun, is 46 million kilometres away at its closest point. None of the extrasolar planets has been seen with telescopes. They are detected indirectly by the effects of gravity on the motions of their mother star. Calculations of the changes in motion of these stars allow astronomers to draw conclusions on the orbit of the planets, their mass and their distance from the central stars. A major problem affecting observation using current telescope technology is that light shining from the stars tends drown all weaker sources of light in the vicinity. An international team of astronomers has discovered 11 new planets outside the solar system, raising fresh ______ about the possibility of life in outer space.
A.
exploring
B.
debate
C.
wondering
D.
pondering
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【单选题】“到现在为止。历史上的一切伟大的活动之所以一开始就是不成功的和没有实际成效的,正是因为他们引起了群众的关怀和唤起了群众的热情。换句话说,这些活动之所以必然得到悲惨的结局,是因为作为它们的基础的思想是这样一种观念:它必须满足于对自己的表面了解,因而也就是指望博得群众的喝彩”,这种观点
A.
意识到了群众的盲目性与不可控性
B.
是否认历史偶然性的机械论
C.
是科学历史观
D.
否定了人民群众是历史创造者
【单选题】既位于北半球又位于西半球的洲是(  )
A.
亚洲
B.
非洲
C.
北美洲
D.
欧洲
【简答题】A. This morning. B. This afternoon. C. Last night. D. Yesterday.
【单选题】那么关于体育健身运动的起源,也可以归结为( ),需要是一切人类活动的动因。因此最初人类对教育、文化娱乐、医疗卫生的需要成为了体育健身运动的起源。
A.
需要论
B.
欲望论
C.
生死论
D.
相对论
【单选题】_________是人一切活动的起因,是产生动机的最根本的动力。
A.
兴趣
B.
信念
C.
世界观
D.
需要
【单选题】He has _____ a number of journals this morning for the information he needs badly.
A.
looked through
B.
looked on
C.
looked over
D.
looked at
【单选题】听力原文:W: Hi, Robert. You look tired this morning. M: I am not feeling well this morning because I stayed up all night and solved the math problems. Q: What did the man do last night? (18)
A.
He slept for a while and studied a little.
B.
He didn't do anything in particular.
C.
He couldn't sleep well because of his illness.
D.
He studied mathematics all night.
【简答题】液压控制阀按连接方式不同,主要有 、 、 插装式三种连接
【单选题】科学家在研究中发现 , 寂寞可能部分是由于基因遗传 , 但如果你能够与其他人接触 , 参加团体活动等并且避免与外界隔绝 , 你就可能建立起一个丰富的人际关系网络。这说明 ( ) 1 事物的联系是普遍的、多样的 2 人为事物的联系的形成离不开实践这一客观物质性活动 3 离开了人的实践活动 , 自在事物的联系是不能实现的 4 一切事物的存在和发展都是有条件的
A.
①②③
B.
①②④
C.
①③④
D.
②③④
【简答题】感觉是“复杂经验建立的基本过程”,因此也是人类一切认知和思维活动的起点。它主要具有两个方面的功能:
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