The wonderful phenomenon known as the Milky Way, which is a marked feature in the sky at this season
What scientists have thought of it
The Galaxy, or Milky Way, is familiar to all readers, and although visible all the year ’round is perceived more plainly in August, September and October, or at the beginning and ending of that period. This zone of stars was well known to the ancients, but Galileo was the first to decide that it is formed of stars. To Sir John Herschel, much of the information we have concerning the Milky Way is due.
In this wonderful zone of stars, the center of our system, the sun, is placed. It was supposed to be divided as in the diagram here given [below left], the inner portion being the stars seen in their thickness, and the outer ring representing the stars viewed in the direction of the length and breadth. But afterward Herschel modified his opinions respecting the Milky Way, and Professor Nichol, among more recent astronomers, says:
“It is only to the most careless glance that the Milky Way appears a continuous zone. Let the naked eye rest thoughtfully on any part of it, and if circumstances are favorable, it will stand out rather as an accumulation of patches and streams of light in every conceivable variety of form and brightness.”
The Milky Way has its greatest breadth in the “Swan,” and in the “Eagle” constellation it divides itself. In the “Southern Triangle,” the zone is brightest, and in the “Southern Cross” the hole or space, termed by the sailors the “Coal Sack,” is very distinct. It then contracts and expands, and there is in Argo another gap. Then it is lost for a space, then it branches out, and soon crosses the Equator, dilates, contracts, opens out again and so returns to the “Swan” again.
Philosophers have discovered much upon this phenomenon, but all statements must remain more or lees speculative. Mr R Proctor has likened the Galaxy to a coiled serpent, and considers the openings in the Milky Way as evidence that the stratum of stars is limited, and that here we can see beyond it.
In fact, it would appear that it is a very complicated question; and as the zone itself is “complicated with outlying branches beyond the range of our most powerful telescopes,” so an actual knowledge of the Milky Way is beyond us at present. It is composed of most extraordinary aggregations of stars, which appear not only impossible to count, but each one to be independent of the other.
Main photo: Part of the Milky Way, from a study made during the years 1874, 1875 and 1876 by E L Trouvelot