基本解释[天文学]星周包层英汉例句双语例句But the larger envelope of circumstellar dust extends some 60 billion kilometers into space, equivalent to about 400 times the Earth-Sun distance.但是拱星四周星尘更大的外壳可以向宇宙延伸600多亿公里，相当于地球到太阳距离的400倍。circumstellar envelope更多例句专业释义天文学星周包层