Many people don’t know that junk has become a problem in outer space. According to BBC News, there are more than 22, 000 pieces of space junk floating around the earth. And some of 【小题1】 are just the things that we just can see from the surface of the earth by telescopes. Objects, like bits of old space rockets or satellites, move around the planet at very 【小题2】 /haɪ/ speeds. Therefore, even a very small piece can break important satellites or become dangerous to 【小题3】 (astronaut). To make things 【小题4】 (bad), when two objects in space crash, they break into many smaller pieces. For example, when a U.S. satellite hit 【小题5】 old Russian rocket in 2009, it broke into more than 2,000 pieces, increasing the amount of space junk. Many scientists are 【小题6】 /ˈɔ:lsəʊ/ suggesting different ways to clean up space junk. In England, scientists are testing a metal net that can be 【小题7】（send） into space. The net catches the junk and then pulls it 【小题8】 the earth’s atmosphere to burn up. The Germans are building robots that can collect pieces of space junk and bring them back to Earth to be 【小题9】（safe）destroyed. “The problem is becoming more challenging because we’re sending more objects into space to help people 【小题10】 /ju:s/ their mobile phones and computers.” says Marco Castronuovo, an Italian space researcher.
