[简答题]They were, by far, the largest and most distant objects that scientists had ever detected: a strip of enormous cosmic cloud some 15 billion light-years from earth. 71. But even more important, it was the farthest that scientists had been able to look into the past, for what they were seeing were the patterns and structures that existed 15 billion years ago. That was just about the moment that the universe was born. What the researchers found was at once both amazing and expected: the US National Aeronautics and Space Administration’’s Cosmic Background Explorer satellite―Cobe―had discovered landmark evidence that the universe did in fact begin with the primeval explosion that has become known as the Big Bang (the theory that the universe originated in an explosion from a single mass of energy). 　　72. The existence of the giant clouds was virtually required for the Big Bang, first put forward in the 1920s,to maintain its reign as the dominant explanation of the cosmos. According to the