"Venus has nothing," is the blunt word from planetologist Kevin Zahnle of NASA Ames Research Center in California&39;s Silicon Valley. "We&39;ve written it off. "
Yet a small group of advanced life-forms on Earth begs to differ. and theorizes that bizarre microbial ecosystems might have once populated Venus and. in fact. may be there still. Members of this loose band of researchers suggest that their colleagues have water too much on the brain, and are, in a sense, H2O chauvinists(盲目的爱国者).
"Astrobiologists are neglecting Venus due more io narrow thinking than actual knowledge of the environment,or environments. where life can thrive." says Dirk Schulze-Makuch, a geobiologist at the University of Texas at El Paso who recently co-authored a Venus-boosting paper in Astrobiology wich colleague Louis Irwin.
The bias against life on Venus is partly rooted in our own biology. Human experience instructs that liquidwater, preferably lot of it. is essential for life. In search for extraterrestrial life, we obsess over small rivers in Mars&39; surface apparently carved by ancient gushes of water. and delight in hints of permafrost (永久冻结带) just underneath its surface. (By comparison. Venus isn&39;t even that interesting to look at:A boring cue ball (台球的白色母球) for backyard astronomers, its clouds reflects 75% of visible light.) Attention and then funding follow the water: Three more landers will depart for Mars this spring. and serious plans for sample-return missions hover in the midterm future.
"If you have limited resources, you base exploration on what you know." says Arizona State University planetary geologist Ronal Greeley. It&39;s like losing your keys on the way home al night: The first place you look is under the streetlights not because they&39;re more likely to be there. but because if they are. you’llspot them. For astrobiologists. the streetlights are the spectral (光谱的) lines for water. and they&39;ve spotted that potential on Mars, Jupiter&39;s moon Europa. even Neptune&39;s moon Triton. Not on the baking rocky flats of Venus.
测试题
Venus is the hottest of all the nine planets in the solar system because_____________.
A.it
J.many
K.it
L.greenhouse
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A.you
B.is
C.is
D.has
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A.
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Where should you begin your research on complex and serious topics?()
Which of the following statements is NOT true about ISEP?()
Which of the following best describes students like Li Xiang?()
I am going(A)to have my letter type(B)tomorrow if I've got(C)everything ready(D)by then.
In his brilliant essay“At the Head of the Peach Blossom Stream”,the great poet of the Eastern Jin Dynasty Tao Yuanming (1)_____(describe)a land of peace away from the turmoil of the world.But where on earth(2)_____(be)this ancient Shangri-la?There(3)_____(be)many guesses. Most people,especially those from Tao Yuanming's native place.(4)_____(believe)that it should(5)_____(be)what(6)_____(be)now(7)_____(call)the Yujing Hill,about two miles west of Star Child County (Xingzixian in Chinese),Jiangxi Province.The Yujing Hill(8)_____(wedge)between the picturesque Mount Lu and the mist-shrouded Poyang Lake.(9)_____(stand)at the summit of the hill and(10)_____(look)around,one(11)_____(see)down below level fields(12)_____(stud)with hamlets and villages,where cottages(13)_____(stand)in neat rows,footpaths(14)_____(crisscross)the farmland,and rice ears(15)_____(wave)in the winds.This(16)_____(be)just the picture(17)_____(depict)by the poet in his lines; Level fields(18)_____(extend)wavily to the far horizon, A new life(19)_____(flow)in lusty young seedlings. (20)_____(look)farther into the distance,one(21)_____(see)vast expanses of blue waters and a solitary,abrupt peak(22)_____(tower)amidst floating mists.This(23)_____(be)just the Fallen Star Hill(Luoxingshan in Chinese)(24)_____(praise)by the poet as“a solitary object of beauty that(25)_____(rise)clear out of the ground beside waters.” (26)_____(take)a closer look,one(27)_____(see)chimney smoke(28)_____(curl)up fromthe cottages at the foot of the hill,children(29)_____(frolic)on the threshing grounds or in the streams amid flocks of fowls,and farmers(30)_____(walk)briskly and(31)_____(work)busily in the fields.This(32)_____(be)just the scene of a contented life of plenty(33)_____(paint)by the poet in hisessay“At the Head of the Peach Blossom Stream”.
【9】:()
【11】:()
Which of the following can be the best title for this passage?()
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