問題詳情

(2) On Tuesday, at a conference in Jackson Hole, Wyoming, a team of Europeanscientists revealed the discovery of at least 50 new worlds. One of them, known as HD85512 b, circles a star about 36 light-years away in the constellation Vela, or at a quarterof the distance that Earth circles the sun. The planet sits just inside its sun’s habitablezone, where liquid water, and perhaps even life, could potentially exist.“And it’s [possible] that it could be habitable,” says Geoff Marcy, who leads adifferent team of planet hunters at the University of California, Berkeley.Possible is the best word anyone can say for now. A clearer answer will have towait for more powerful telescopes to be built. The question of whether 85512 bactually is home to life will depend on many factors. Does 85512 b have any water tostart with? Does it have a solid, rocky surface on which life can live? Does it have a cloudlayer to avoid overheating from its sun?Nobody knows. After all, so many conditions must fall in line. The new world is stilla big deal, though. It proves that astronomers now have the technology to find thesekinds of planets.The 50 new planets announced in Wyoming were discovered from the ground witha device called the High Accuracy Radial velocity Planet Searcher, or HARPS to look for astar’s slight wobble. The wobbles occur when the gravity of an orbiting planet tugs thestar one way, then the other. The very first exoplanets were found this way. An exoplanetis a planet that orbits a distant star other than our sun.
48. Based on the news item, which of the following is NOT a decisive factor for a planetto have life?
(A) It contains water.
(B) It has a solid, rocky surface.
(C) It has to be about the size of the earth.
(D) It has a cooling cloud layer.

參考答案

答案：C
難度：適中0.5
統計：A(0),B(0),C(0),D(0),E(0)

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