共用题干 第三篇Small but WiseOn December 14,NASA blasted a small but mighty telesco...

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问题 共用题干 第三篇

Small but Wise

On December 14,NASA blasted a small but mighty telescope into space.The telescope is called WISE
and is about as wide around as a trashcan.Don't let its small size fool you:WISE has a powerful digital
camera,and it will be taking pictures of some of the wildest objects in the known universe,including
asteroids,faint stars,blazing galaxies and giant clouds of dust where planets and stars are born.
"I'm very excited because we're going to be seeing parts of the universe that we haven't seen be-
fore,"said Ned Wright,a scientist who directs the WISE project.
Since arriving in space,the WISE telescope has been circling the Earth,held by gravity in a polar orbit
(this means it crosses close to the north and south poles with each lap).Its camera is pointed outward,away
from the Earth,and WISE will snap a picture of a different part of the sky every 11 minutes.After six months
it will have taken pictures across the entire sky.
The pictures taken by WISE won't be like everyday digital photographs,however. WISE stands for
"Wide-field Infrared Survey Explorer".As its name suggests,the WISE camera takes pictures of features
that give off infrared radiation.
Radiation is energy that travels as a wave.Visible light,including the familiar spectrum of light that be-
comes visible in a rainbow,is an example of radiation.When an ordinary digital camera takes a picture of a
tree,for example,it receives the waves of visible light that are reflected off the tree.When these waves enter
the camera through the lens,they're processed by the camera,which then puts the image together.
Waves of infrared radiation are longer than waves of visible light,so ordinary digital cameras don't see
them,and neither do the eyes of human beings.Although invisible to the eye,longer infrared radiation can
be detected as warmth by the skin.
That's a key idea to why WISE will be able to see things other telescopes can't. Not everything in the
universe shows up in visible light.Asteroids,for example, are giant rocks that float through space一but they
absorb most of the light that reaches them.They don't reflect light,so they're difficult to see.But they do
give off infrared radiation,so an infrared telescope like WISE will be able to produce images of them.During
its mission WISE will take pictures of hundreds of thousands of asteroids.
Brown dwarfs are another kind of deep-space objects that will show up in WISE's pictures.These ob-
jects are "failed" stars一which means they are not massive enough to jump-start the same kind of reactions
that power stars such as the sun.Instead,brown dwarfs simply shrink and cool down.They're so dim that
they're almost impossible to see with visible light,but in the infrared spectrum they glow.
选项 It is true that infrared radiation_________. A:is not detectable to humans B:looks brighter than visible light C:is visible light reflected off an object D:has longer waves than those of visible light
答案 D
解析 由文章前两段内容可知,这个太空望远镜携带的数码相机可以拍到我们未知的宇宙里 的众多物体,它将使人类看到宇宙中的未知部分,故选C。
这个太空望远镜其实是个广视场红外线探测器(Wide-field Infrared Survey Explorer),它 能拍到产生红外线辐射的物体,故选B。
由文章第六段内容可知,红外线辐射波比可见光的波长更长,因此普通的相机和肉眼 都是看不到它们的,但是红外线波可由皮肤感知,故本题选D。
由文章第七段第二、三句“Not everything in the universe shows up in visible light.Asteroids , for example...”可知,不是所有的物体都是以可见光的形式被发现的,小行星就是一 例,它们发出红外线,太空望远镜WISE可以感测到,故选C。
由最后一段内容可知,棕矮星能够被WISE探测到,说明它们发射的光不是可见光,而 是红外线波,故选A。

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