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Small But Wise On December 14,NASA1 blasted a small but mighty telescope into space. The telescope is called WISE and is about as wide around as a trashcan. Dont let its small size fool you:WISE has a powerful digital camera, and it will be taking pictures of some the wildest objects2 in the known universe,including asteroids,faint stars,blazing galaxies3 and giant clouds of dust where planets and stars are born. Since arriving in space,the WISE telescope has been circling the Earth,held by gravity in a polar orbit4.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. Radiation is energy that travels as a wave. Visible light, including the familiar spectrum of light7 that becomes 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,theyre processed by the camera,which then puts the image together. Thats a key idea to why WISE will be able to see things other telescopes cant. 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 dont reflect light,so theyre 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. | 
