Page:Astronomy for Everybody.djvu/349

If I were asked what is the greatest fact that the intellect of man has ever brought to light I should say it was this:

Through all human history, nay, so far as we can discover, from the infancy of time, our solar system—sun, planets, and moons—has been flying through space toward the constellation Lyra with a speed of which we have no example on earth. To form a conception of this fact the reader has only to look at the beautiful Lyra and reflect that for every second that the clock tells off, we are ten miles nearer to that constellation. Every day that we live we are nearer to it by almost, perhaps quite, a million of miles. For every sentence that we utter, for every step that we take in the streets we are miles nearer to this star. We approached it by tens of thousands of miles while the writer has been penning these lines, and the reader has been carried nearer by a thousand miles while perusing them. This has been going on through all human history, and we have reason to believe that it will remain true for our remotest posterity. One of the greatest problems of astronomy is, when and how did this journey begin and when and how will it end? Before this question our science stands dumb. The astronomer can tell no more about the beginning or the end of the