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来源:雅诚德英语网
Spiral galaxies, such as the Milky Way, consist of a flat disk with a bulging center and surrounding spiral arms.
象银河系一样,螺旋星系由一个中间鼓起的扁圆盘和环绕在周围的螺旋形手臂组成。
Spiral galaxies, such as the Milky Way, consist of a flat disk with a bulging center and surrounding spiral arms.
象银河系一样,螺旋星系由一个中间鼓起的扁圆盘和环绕在周围的螺旋形手臂组成。