2015年考研英语阅读理解精选20篇(第三篇)

　　考研英语中阅读理解是重头戏，所占比例较大，考生在复习提高的过程中需要多付出精力。可是对于阅读理解来说，要提高并不是一蹴而就的事情，阅读能力需要日积月累，才能够提高速度和做题的技巧效率。为此，新东方在线小编为广大考生奉上20篇阅读理解，希望大家通过积累来最终提升综合阅读能力。

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　　远离故土的家

　　The existence of the most Earthlike planet yet has just been confirmed

　　Dec 10th 2011 | from the print edition

　　ONE of the more memorable slogans to come out of the climate-change talks in Durban over the past few days is: “there is no planet B”. But what if there were? Over the past couple of decades astronomers have logged thousands of so-called “exoplanets”—worlds which orbit stars other than the sun. On December 5th the scientists in charge of Kepler, a space telescope designed to look for such planets, confirmed their instrument’s discovery of its first Earthlike world. It is dubbed, rather unromantically, Kepler 22b.

　　The existence of this planet, which circles a star 600 light-years away, in the constellation of Lyra, had previously been suspected. Kepler, which belongs to NASA, America’s space agency, works by observing dips in a star’s brightness as a planet passes in front of it. It flags likely looking reductions as “candidate planets”, of which Kepler 22b was one. But three passes are needed to confirm a planet’s existence, and Kepler 22b has now passed this test. Crucially, it orbits well within its star’s “Goldilocks zone”: neither too close nor too far away for liquid water (and therefore, perhaps, life) to exist on its surface.

　　It joins two other Earthlike planets—Gliese 581d and HD 85512 b—discovered by another instrument within the past few years. In truth, the term “Earthlike” is a stretch. Kepler 22b has a radius 2.4 times that of Earth, and if it is made from roughly the same stuff its surface gravity will also be about 2.4 times as strong. But NASA’s astronomers remain unsure whether it is predominantly gaseous, liquid or solid.

　　Nevertheless, Kepler 22b is the most promising exoplanet yet found. Unlike the others, which skirt the edges of their stars’ Goldilocks zones, Kepler 22b orbits comfortably within its own. NASA’s researchers reckon its surface temperature is about 22°C, compared with 15°C (at least for now) on Earth. Its parent star is similar to the sun, again unlike those of the other two candidates, both of which orbit cooler, dimmer stars. Indeed Gliese 581d’s parent is a red dwarf—the tiniest stellar species. That means its Goldilocks zone is so close to it that the planet may be tidally locked, as the moon is to the Earth. If that were the case, one side of Gliese 581d would be permanently lit (and heated) while the other experienced unending darkness.

　　These three potentially habitable exoplanets may soon be joined by many more. In the two and a half years since its launch, Kepler has spotted 2,326 candidate planets. About 650 others have been discovered by other instruments. That plethora allows astronomers to start drawing conclusions about how common various sorts of planets are. Of Kepler’s haul, 9% seem to be of a similar size to Earth (though not all are in the Goldilocks zone of their star); a further 29% are Super Earths—planets substantially larger than Earth that are nevertheless rocky. Forty-eight of Kepler’s unconfirmed candidates look as if they orbit within their stars’ habitable zones; of those, ten seem to be Earth-sized.

　　The ultimate goal, of course, is to let astronomers make a plausible estimate of the total number of planets in the galaxy, of the number that could conceivably support life, and of the fraction of those that could (at least in theory) sustain human colonists. If only a few of Kepler’s possible Earthlike planets turn out to be real, that third number is likely to be in the millions.

　　Such knowledge will mark an historic transition, says Chris Lintott, an astronomer at Oxford University who is giving the Kepler team a hand with the data analysis, since the uncertainties around the question of whether life exists elsewhere will cease to be astronomical (how many suitable planets are there?) and become purely biological (how easy is it for life to get going, and how easy is it for it to become intelligent?). Based on the preliminary data, it looks as if there are numerous suitable planets. The science of exobiology may soon cease to be an oxymoron.

　　付出会有回报，提高需要努力，小编希望每一位决定了考研的考生都能够坚定自己的目标，并为实现目标努力奋斗，坚持不懈，只有这样才能收获丰厚的果实。2015年考研圆梦，大家一起努力。

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