Our galaxy is so huge that dozens of lesser galaxies scamper about it, like moons orbiting a giant planet.
我们的银河系实在庞大,吸引着数十个较小的星系环绕着它奔跑,恰似环绕巨大行星旋转的卫星。
But such transits have paved the way for what might prove to be one of the most vital breakthroughs in the cosmos—detecting Earth-sized planets orbiting other stars.
但是这样的凌日现象已经为被证明可能是宇宙中最重要的突破之一的说法铺平了道路,这个说法即找到那些围绕其他恒星轨道公转的和地球大小相似的行星。