Ancient Water From Afar It streaked across the sky on a warm March evening last year, then crashed into a street in the sma

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问题                                     Ancient Water From Afar
     It streaked across the sky on a warm March evening last year, then crashed into a street in the small town of Monahans, Texas. When seven boys quit their basketball game to inspect the damage, they found a shiny, black grapefruit-size rock settled in the asphalt (沥青). Word of the “flaming rock” traveled quickly in newspapers and on TV. The next day, NASA scientist Everett Gibson arrived and took the meteorite(陨石) , later named Monahans 1998, back to a lab in Houston. There researchers broke open the extraterrestrial (地球外的)rock with a hammer and chisel (凿子). To their surprise, they struck water. A team led by Michael Zolensky of the Johnson Space Center reports this discovery in a journal. It’s the first time anyone has found liquid water in an object from space—and a suggestion that life may exist out side our planet.
     Meteorites containing water are probably not scarce, Zolensky says. But by the time researchers get their hands on the rocks, minerals that trap the water have dissolved away, and the water have evaporated. Worse, some researchers destroy the evidence by cutting meteor ites open with rock saws and water. “I’m betting this isn’t such a rare finds it’s just that people have been mistreating their meteorites,” Zolensky says.
     Of course, Zolensky’s team did get a bit lucky. Monahans 1998 was safe in their lab less than two days after it hit the Earth, so they examined an unusually fresh sample. The scientists were keen to find vivid purple crystals of halite (岩盐)inside the meteorite, since halite is a salt mineral usually formed from liquid water. Even more curious were the hundreds of tiny bubbles suspended in the halite crystals. Zolensky’s team analyzed the bubbles by shining a laser beam through them and confirmed they were made of salty brine (盐水).
     By dating the halite, Zolensky’s team found the water trapped inside it formed at least 4.5 billion years ago, back when most scientists believe our solar system was born. That means the briny object amy help researchers learn about the gaseous nebulas(星云)that gave rise to our sun and planets.
     But how did the meteorite get wet? One possibility is that a passing comet smashed into the rock, dropping off a load of liquid water. Or the rock might have chipped off an asteroid (小行星)that holds pools of fluid. Zolensky’s team still needs to study whether the water comes from our own solar system. One thing is certain, however: the Monahans meteorite will fuel the debate on extraterrestrial life, “Water is a life-giver, so if you want to study where life came from in the solar system, you have to follow where water came from,” Zolensky says. A wet rock from space doesn’t mean little green men are coming soon to a planet near you, but it does raise hopes that we’re not alone in the universe.  
The rock clipped off an asteroid that held pools of water.

选项 A、Right
B、Wrong
C、Not mentioned

答案A

解析 答案在最后一段第三句。即“这块岩石可能显示有一个小行星上面曾经有过水池”这句话。
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