Rings of Saturn

“ We rose still higher. The Sun and its system were rapidly passing. The Earth was but a little spot now; Jupiter himself, that colossal world, had melted away, like Mars and Venus, to a tiny little dot scarcely larger than the Earth. We passed within sight of Saturn, surrounded [21] by his gigantic rings, whose study alone would be sufficient to prove the immense and unimaginable variety reigning in the universe. Saturn is a whole system in itself, with its rings composed of particles torn from it in its dizzy revolution, and with its eight satellites accompanying it like a celestial retinue. ”

“ We have no reason to look upon the rings of Saturn otherwise than as in process of being converted into one or more satellites, most probably more than one; because if the matter they are composed of has been separated from the planet in the form of a sheet, the same as we have seen must have been the case with the matter separated from the original nebula for the planets, the sheet has been already divided into at least three distinct parts, and surely that cannot have been done without some object. ”

“ Nothing like them is to be seen elsewhere in the heavens; and when well opened they form, with the globe they inclose, and the retinue of satellites in waiting outside, a strange and wonderful telescopic object. The rings, since they lie in the plane of Saturn’s equator, are inclined 27° to the Saturnian orbit, and 28° to the ecliptic. The earth is, however, comparatively to Saturn, so near the sun, that their variations in aspect, as viewed from it, may in a rough way be considered the same as if seen from the sun. ”

“ The mechanical behaviour of a system of rings, on different hypotheses as to their constitution, has been worked out with consummate skill by Clerk Maxwell; who finds that the only possible constitution for Saturn's assemblage of rings is a multitude of discrete particles each pursuing its independent orbit. Saturn's ring is, in fact, a very concentrated zone of minor asteroids, and there is every reason to conclude that the origin of the solar asteroids cannot be very unlike the origin of the Saturnian ones. The nebular hypothesis lends itself readily to both. ”

“ The first sign of a “spreading outward” should be the formation of an exterior “crape ring,” of which no faintest trace has yet been perceived.
Saturn’s rings are entirely invisible from its polar regions, but occasion prolonged and complex eclipse-effects in its temperate and equatorial zones. They have been fully treated of from the geometrical point of view by Mr. Proctor in Saturn and its System.
Of this planet’s eight satellites, [28] the largest, Titan [424] (No. VI) , was discovered first (by Huygens in 1655) , and the smallest, Hyperion (No. VII) , last (by Lassell and Bond in 1848) . ”

“ The rings of Saturn replace, in Professor G. H. Darwin's view, [1115] an abortive satellite, scattered by tidal action into annular form. For they lie closer to the planet than is consistent with the integrity of a revolving body of reasonable bulk. The limit of possible existence for such a mass was fixed by Roche of Montpellier, in 1848, [1116] at 2·44 mean radii of its primary; while the outer edge of the ring-system is distant 2·38 radii of Saturn from his centre. The virtual discovery of its pulverulent condition dates, then, according to Professor Darwin, from 1848. ”

“ The appearance of Saturn is unparalleled in the system of the world; he is surrounded by a ring even brighter than himself, which always remains in the plane of his equator, and viewed with a very good telescope, it is found to consist of two concentric rings, divided by a dark band. By the laws of mechanics, it is impossible that this body can retain its position by the adhesion of its particles alone; it must necessarily revolve with a velocity that will generate a centrifugal force sufficient to balance the attraction of Saturn. ”

“ Sometimes for days together a large part of Saturn must suffer eclipse beneath the encircling rings, but at other times, at night, when the rings are clear of the planet's body, so that the light is not cut off from them, they must appear as radiant arches of glory spanning the sky. ”

“ Sometimes we can only see them edgewise, and then even in the largest telescope they are only like a streak of light, and this shows that they cannot be more than fifty or sixty miles in thickness. The one which is nearest to Saturn's surface does not approach him within ten thousand miles. Saturn has no less than ten satellites, in addition to the rings, so that his midnight sky must present a magnificent spectacle. The rings, which do not shine by their own light but by reflected sunlight, are solid enough to throw a shadow on the body of the planet, and themselves receive his shadow. ”

“ Already there have been surprises and puzzles that paint a completely new picture of Saturn and its neighborhood, including the discovery of three new moons, startling information about Saturn’s rings, and observation of the unexpectedly complex structure of Saturn’s atmosphere and that of its largest moon, Titan. It will take years for scientists to assimilate completely the information which is cascading down from Voyager. What more will this marvel of technology have to tell us before it departs the solar system to travel endlessly among the stars? ”

“ If at any time it should disperse, it would either fall into fragments upon the surface of Saturn, or the fragments, mutually coalescing, would form additional satellites to circle round the planet in its path.
To any observer stationed on the planet, between the extremes of lat. 45 degrees on either side of the equator, these wonderful rings would present various strange phenomena. Sometimes they would appear as an illuminated arch, with the shadow of Saturn passing over it like the hour-hand over a dial; at other times they would be like a semi-aureole of light. ”

“ Suppose that in the course of its motion through the heavens the path of Saturn happened to cross directly between the earth and a fixed star. The telescopic appearance of a star is merely a point of light much smaller than the globes and rings of Saturn. ”

“ When we see Saturn presented as a ball within a ring, or more carefully pictured as a striped globe within a system of rings, we are apt to regard the ideas suggested by such drawings as affording a true estimate of the planet's nature. In fact, many believe that the planet and its rings are really like what is presented in these pictures. It should be understood that what has been actually seen of Saturn by telescopic means cannot, in the nature of things, afford any true picture of the planet and its ring system. ”

“ Saturn has eight moons and is surrounded with the rings which have made it famous from the time the planet was first seen through the telescope. These rings and moons are inhabited by a type of human beings altogether different from those that live on the planet, and are distinctly visible to the dwellers of Saturn by means of powerful telescopes.
The human beings on the rings are not able to watch their neighbors in space, having no instruments to carry their vision beyond the boundaries of their own peculiar abodes. ”

“ Perhaps the most striking fact that becomes conspicuous in making such a model [Pg 197] of the Saturnian system is the exceeding thinness of the rings as compared with their enormous extent. They are about 170,000 miles across from outer edge to outer edge, and about 38,000 miles broad from outer edge to inner edge—including the gauze ring presently to be mentioned—yet their thickness probably does not surpass one hundred miles! In fact, the sheet of paper in our imaginary model is several times too thick to represent the true relative thickness of Saturn's rings. ”

“ Thus turning, it divided into successively formed rings, each of which in time broke up, the matter of the ring gathering into a separate planet. At first this planet, like the original mass, was gaslike, and when separated from the sun it began to gather in on itself, in most cases forming rings, which in time were to alter into the lesser spheres—the moons. The earth and all the planets lying further away from the sun have these little bodies about them, but in one case, as if to show the stages of creation, the unbroken ring remains, forming the magnificent circles which girdle Saturn. ”

“ If a model about a foot in diameter were cut out of tissue paper, the relative proportion of size and thickness would be about right. In space the thickness is very nearly 100 miles, so that, when we look at the ring system edge-on, it becomes all but invisible except in very large telescopes. Clearly a ring so thin cannot be a continuous solid object and recent observations have proved beyond a doubt that Saturn's rings are made up of millions of separate particles moving round the planet, each as if it were an individual satellite. ”

“ Even if all the satellites could be full together, they would not supply a sixteenth part of the light which we receive from our full moon; and they cannot even appear very beautiful when we consider that the apparent brightness of their surface can be but about one-ninetieth of the brightness of our moon's. As for the rings, so far from appearing to be contrived specially for the advantage of Saturnian beings, these rings, if Saturn were inhabited, would be the most mischievous and inconvenient appendages possible. ”

“ The present time, when Saturn is the ruling planet of the night, seems favourable for giving a brief account of recent speculations respecting the Saturnian ring-system, especially as the observations of Mr. Trouvelot appear to remove all doubt as to the true nature of the rings, if indeed any doubt could reasonably be entertained after the investigations made by European and American astronomers when the dark inner ring had but recently been recognised. ”

“ The earliest successful photograph of Saturn was taken in 1883 by Andrew Common. In 1895, James Keeler suggested that the rings are in fact a swarm of particles in near-independent orbits. These rings, until the recent discoveries of faint ring systems around Jupiter and Uranus, were considered unique in the solar system.
Since Galileo first used his homemade telescope to view Saturn, there have been many observers. There have also been major advances in telescopes; a resulting modern view of Saturn is shown on the next page. ”

“ Saturn's rings present the only case within the solar system where matter is known to be revolving about a planet at a distance less than Roche's limit, and it is an interesting question whether these rings can remain as a permanent part of the planet's system or are only a temporary feature. ”

“ The strange problem presented by the rings, which naturally conceal the sun from immense regions of the planet for years together in the very heart of the winter of those regions, is satisfactorily solved when the Saturnian satellites are regarded as the abodes of life, and Saturn himself as the source of a considerable proportion of their heat-supply. We do not say that, in thus exhibiting the Jovian and Saturnian systems in a manner which accords with our ideas respecting the laws of life in the universe, we have given irrefragable testimony in favor of our theory. ”

“ The problems of Saturn are much the same as those of Jupiter, excepting that the surface and atmospheric phenomena are less striking, and more difficult of observation. But we have, in addition, the wonderful rings, unique in the heavens, the loveliest of all telescopic objects, the type and pattern, I suppose, of world-making, in actual progress before our eyes. ”

“ The drawings of Saturn made two centuries ago agree among themselves in representing the rings as larger than they now appear, and there is some reason to suppose that as a consequence of mutual disturbances—collisions—their momentum is being slowly wasted so that ultimately they must be precipitated into the planet. ”

“ When the ring appears like a very narrow ellipse, a short time previous to its disappearance, the division, or dark space between the rings, cannot be seen by ordinary instruments.
Sir W. Herschel very properly observes, ‘There is not perhaps another object in the heavens that presents us with such a variety of extraordinary phenomena as the planet Saturn; a magnificent globe, encompassed by a stupendous double ring; attended by seven satellites; ornamented with equatorial belts; compressed at the poles; turning upon its axis; mutually eclipsing its ring and satellites, and eclipsed by them ”

“ It is instructive to compare Jupiter and Saturn in this respect with the sun. They are smaller globes and have cooled down more than the central fire.
Saturn is a beautiful object in the telescope because it has ten moons (to include one which is disputed) and a wonderful system of "rings" round it. The so-called rings are a mighty swarm of meteorites--pieces of iron and stone of all sorts and sizes, which reflect the light of the sun to us. This ocean of matter is some miles deep, and stretches from a few thousand miles from the surface of the planet to 172,000 miles out in space. ”

“ So far as one's personal experience goes, Saturn is generally the most easily defined of all the planets. Of late years he has been very badly placed for observers in the Northern Hemisphere, and this has considerably interfered with definition. But when well placed the planet presents a sharpness and steadiness of outline which render him capable of bearing higher magnifying powers than Jupiter, and even than Mars, though a curious rippling movement will often be noticed passing along the rings. ”