The Day After Death; Or, Our Future Life According to Science (New Edition)

by Louis Figuier

With a glass which magnified the apparent diameter of the sun only twenty-sixfold, Galileo, repeating the observations of Fabricius, discovered the spots on the sun. Although Galileo did not use the smoked glasses which have since been found so useful, and although he limited his observations to the horizon, watching the great star at its rising and its setting, or when it was veiled by slight clouds, he studied its spots carefully, and described them faithfully.

We may observe that this discovery astonished the philosophers of that period, who were entirely submissive to the authority of Aristotle. The incorruptibility of the sun was held in the schools as a sacred principle, according to Aristotle, and these unfortunate spots perplexed the philosophers. The peripatetics vied with each other in proving to the Florentine astronomer that the purity of the sun was an unassailable principle, and that the spots which he had perceived existed only on his eyes, or on the lens of his glasses.

But Galileo had seen correctly, and soon every one could convince himself of the reality of the phenomenon he had proclaimed. Not only do spots exist upon the disc of the sun, but they furnish the only means which we possess of becoming acquainted with the physical and astronomical peculiarities and properties of the great star. The examination of these spots led to the discovery that the sun revolves like the other planets, and that he accomplishes the entire revolution upon his axis in a period of twenty-five days. The sun's days are therefore twenty-five times as long as ours. Here, however, we must remark upon the word day. To us, the day signifies the periodical return of the earth to the same point, after a complete revolution upon its axis, with an alternation of light and darkness. It is quite otherwise in the case of the sun, which, being self-luminous in all his parts, can never have any night.

We have said that the examination of the sun's spots established his rotation upon his axis. In fact, if we patiently observe the motion of a spot, or of a group of spots, we remark that it advances slowly from one edge of the solar disc to the other; for instance, if the point of departure be the eastern edge, the spot or group will advance with uniform speed towards the western edge, taking fourteen days to accomplish the distance. If we wait fourteen days more, we shall again perceive the same spot making its appearance on the eastern edge of the disc, the interval having been consumed in passing over the opposite and, of course, invisible side of the sun. The spot has therefore taken twenty-eight days to reappear, which twenty-eight days do not, however, represent the exact duration of the revolution of the sun himself. It must not be forgotten that the earth has not remained motionless during this long observation; she, too, has gone round in the sun, as the spots have done. This sort of advance, which causes us to see the same spot for a longer time than we should have seen it, if the earth remained motionless, is of three days' extent, the deduction of which from the twenty-eight given days, allows twenty-five days for the real duration of the sun's rotation upon his axis.

In the sun seasons are unknown as well as days. Time seems to have no existence for the beings who occupy that radiant dwelling-place. The changes, and the succession of things for us which constitute time, are unknown to their sublime essence. Duration has no measure in that blessed world.

The dweller in the sun must behold the revolution of the planets around him, performed according to the same laws, but with different rates of speed. The phases of the planets and their satellites, the phases of Mars and Venus, or those of the moon, which we perceive from the earth, are unknown to them; they see only the hemisphere of those globes which is illumined by their own immense country. They behold, in larger dimensions, the globes of Mercury and Venus, and in lesser dimensions the Earth and Mars. The distant planets, Jupiter, Saturn, and Uranus, must seem very small to them. Neptune they probably cannot see at all. The comets must be for a long time invisible to the inhabitants of the sun, who behold their flaming mass rushing towards them in ever-increasing size. They also see some comets sinking away into space, and others falling on the surface of the sun himself, to be lost and absorbed in his substance.

Thus, the spots on the sun have revealed to us an important peculiarity of his astronomical character, his revolution upon his axis. They have also given us the only exact ideas which we possess of the physical constitution of the sun.

The accompanying plate conveys an idea of what the spots on the sun consist of. Figures 2 and 3 represent the general aspect of these appearances. In the centre is a black space perfectly marked. To this succeeds a space in grey tinting, whose outlines melt by degrees into the rest of the luminous mass. The first region is called the Umbra; the second, the Penumbra.

These words must be distinctly understood. The part indicated by the term Umbra is only dark relatively to the illumined portion. This Umbra is very luminous, its brilliancy is two thousand times that of the full moon. We are merely dealing with comparisons here. The solar spots are often of very considerable dimensions. They have been found 30,000 leagues in breadth, and could swallow up the earth, which is only one-tenth of that magnitude. They are not permanent, sometimes they remain for months, or even years, but the greater number increase and decrease rapidly, and disappear in a few weeks. They are incessantly changing in form and in extent, and they grow and diminish. It is evident that they are regulated by a violent interior movement, and that they are the seat of tumultuous motion. Something like whirlwinds are seen to sweep across the regions occupied by the spots, and to carry them away, like the waves of a furious sea, or the flames of a conflagration. Gigantic bridges of apparently burning matter have been observed, thrown from one edge to the other of adjacent spots, uniting them by a shining band, and then this same band has stretched itself out and caught hold of other spots. Of a sudden the whole edifice has been seen to be swept away by fresh whirlwinds. Signs of a prodigious commotion, of gigantic perturbation, are always evident. These hurricanes, these tempests of flame, are of a widely different grandeur from the hurricanes and the tempests of our atmosphere, because the atmosphere of the sun is several thousands of yards in height, and covers an extent of surface 1,300,000 times greater than ours.