Watchers of the Sky by Noyes, Alfred, 1880-1958

Then, at a word, the mighty weapon dipped Its muzzle and aimed at one small point of light One seeming insignificant star. The chief, Mounting the ladder, while we held our breath, Looked through the eye-piece. Then we heard him laugh His thanks to God, and hide it in a jest. "A prominence on Jupiter!"-- They laughed, "What do you mean?"--"It's moving," cried the chief, They laughed again, and watched his glimmering face High overhead against that moving tower. "Come up and see, then!" One by one they went, And, though each laughed as he returned to earth, Their souls were in their eyes. Then I, too, looked, And saw that insignificant spark of light Touched with new meaning, beautifully reborn, A swimming world, a perfect rounded pearl, Poised in the violet sky; and, as I gazed, I saw a miracle,--right on its upmost edge A tiny mound of white that slowly rose, Then, like an exquisite seed-pearl, swung quite clear And swam in heaven above its parent world To greet its three bright sister-moons. A moon, Of Jupiter, no more, but clearer far Than mortal eyes had seen before from earth, O, beautiful and clear beyond all dreams Was that one silver phrase of the starry tune Which Galileo's "old discoverer" first Dimly revealed, dissolving into clouds The imagined fabric of our universe. _"Jupiter stands in heaven and will stand Though all the sycophants bark at him,"_ he cried, Hailing the truth before he, too, went down, Whelmed in the cloudy wreckage of that dream.