Page:The Music of the Spheres.djvu/115

 If it lies so far in space that it does not seem to change its position even when viewed from stations on either side of the earth's orbit, its distance may never be measured by using the diameter of the earth's orbit as a baseline.

Even the near stars are so very distant that their displacement is almost imperceptible. The parallax (or the apparent angular shifting caused by the changed position of the observer) of Alpha Centauri, our nearest star, would have, says Professor Moulton, the same difference in direction as a point of light 11 miles from the observer viewed with one eye and then the other, with the difficulties of observation extended over several months.

But to return to Arcturus. This beautiful golden star is called the "harbinger of spring" because it rises on the first of March just as the flowers of this season are awakening along the brooks and hillsides. Watch for it about 8 P. M. just a little north of east. At this point it is at its very best for the thickened atmosphere near the horizon fires the orange-yellow to a molten rose, while the flickering and the dancing causes burning waves of crimson, sparks of opal and glints of gold. It reaches the meridian June 8th about 9 P. M. but its eager, splintering light is now calmed to a steady glow and the star hangs like a golden lamp above the world. From July to December, this splendid star floats lower and lower through the western part of the heavens until it touches the horizon in the northwest and disappears.



The Northern Crown really looks like a crown. Its outline is easily traced, although its stars are delicate with the exception