large telescope, for not only one star is disclosed but three—a sea-green and a blue beside the one of orange-gold!
Just above Mirach, the star on the girdle, are two fainter stars and a small misty object. A large telescope will show that this misty object is a long shuttle-shaped nebula of the most colossal size. This is the famous nebula of Andromeda, the only spiral nebula in the heavens which may be located without a telescope. The nebula of Andromeda is not a gaseous nebula but an outside universe, an aggregation of millions of suns comparable to the Galaxy. (The Galaxy is our Milky Way.) This in itself is astounding, but it is also astounding that we have been privileged to gaze over a chasm so wide that an aggregation of millions of suns looks no more to our eyes than a misty spot of light. Dr. Edwin Hubble, of the Mount Wilson observatory in California, has recently made the discovery that the more distant spiral nebulæ may also be resolved into stars. Dr. Hubble made his investigations photographically with the 60-inch and 100-inch telescopes. Although most of the spiral nebulæ appear very small because they are at least a million light years distant, the nebula of Andromeda is comparatively close, its apparent diameter being about six times the diameter of the moon.
This famous nebula may be most easily located when near the zenith during the latter part of October. Watch for it just after the star Alpheratz, on the head of Andromeda, has passed the meridian and started toward the west. To the unaided eye, it
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