Conversations on the Plurality of Worlds

by M. de Fontenelle

After Mercury, you know, we find the sun. We cannot possibly place inhabitants there: the why not fails in this case. We conclude from the earth being inhabited that other bodies of the same nature must be so too: but the sun does not resemble the earth, and the rest of the planets. He is the source of all that light which the planets only reflect to each other after they have received it from him. They make exchanges, if I may so express myself, with one another, but none of them can bestow an original light. The sun is the sole proprietor of that treasure; which he distributes freely on every side. The light, thus issuing from the centre, is reflected from every solid body it meets, and from one planet to another it proceeds in bright streams that intermix, and cross each other in a thousand directions, forming a splendid tissue of the richest materials. The grand luminary by being placed in the centre is in the most advantageous situation for animating each planet with his heat and radiance. The sun, then, is of a peculiar nature, but what that nature is, we find it difficult to imagine. Formerly it was believed to be a pure fire, but lately we have been undeceived by observing spots on the surface. As certain new planets had just before been discovered, (I shall give you an account of these planets hereafter;) which entirely engrossed the attention of the philosophers, a sort of mania for new planets seized their minds, and they immediately concluded these spots were some; that they performed a circle round the sun, and necessarily concealed some part of his light by turning their dark side towards the earth. The learned already, through these planets, complimented the different princes of Europe. Some gave them the name of one prince; some of another, and perhaps in time there would have been a great contest to know who had the best right to name these spots.

I don't like their plan, said the Marchioness. You told me, the other day, that the different parts of the moon were named after learned men; I thought that very proper: as princes monopolize the earth, it is but fair that astronomers should have the sky for their share, and not suffer princes to intrude on their domain. Allow them, however, I replied, if territory should be wanting, to consign to them some planet, or some part of the moon. As to these spots on the sun, they can make no use of them; for instead of planets, we find they are only clouds of smoke or dross arising from the sun. Sometimes these clouds are greatly accumulated, sometimes we see little of them, and at other times they totally disappear. Sometimes a number of them are combined together, then they are separated into small parts; at one time they are very dark, at another they grow pale. It appears as if the sun was some kind of liquid; many people think it is melted gold, in a continual state of ebullition, producing impurities, which the rapidity of its motion casts up from the surface; they are afterwards consumed and others produced. Only think what amazing bodies these are. Some of them are seventeen hundred times[34] larger than the earth, for you must know, the earth is more than a million times smaller than the sun.[35] Imagine therefore what must be the quantity of this liquid gold, or the extent of this ocean of light and fire!

[34] The largest of the sun's spots are scarcely three times larger than the diameter of the earth, or twenty-seven times its bulk.

[35] The earth is only a hundred, or to speak with more exactness, a hundred and eleven times, smaller.

Other philosophers say, and with great plausibility, that the spots, or at least the greatest part of them, are not newly produced, and then destroyed after a certain time; but large, solid, masses, of irregular forms, always subsisting; sometimes floating on the surface of the sun, sometimes partly, or entirely buried in the liquid substance, and presenting to our view different projections according to the size of the part that remains uncovered. Perhaps they may be parts of some great mass of matter which serves as aliment to the fire of the sun. However, let the sun be what it will, it does not by any means appear habitable.[36] It is a pity; the situation would be advantageous: placed at the centre, its inhabitants would see the planets going round them in regular orbits, whilst to us their motions seem to have perplexing varieties, which are merely the effect of our not observing them from the best place; that is, the centre of their circles. What a sad thing it is: there is but one spot where the study of the celestial bodies would be extremely easy, and at that spot there is nobody to pursue the study. You forget yourself, answered the Marchioness. Were any one placed on the sun, he would neither see the planets nor the fixed stars; would not the light of the sun efface every other object? The inhabitants would doubtless think themselves the only people in existence.

[36] Some natural philosophers have however thought that the sun might be the cause of heat without being itself hot; and that there was a possibility of its being inhabited. M. Herschel believes its population very abundant. Trans. Philos. 1795. Décade Philosophique.

I acknowledge my error, I replied: I was thinking of the situation of the sun, without considering the effect of such an excessive light: but although you have so properly corrected my mistake, yet you must allow me to tell you that you have fallen into one yourself. The inhabitants of the sun would not see any thing: they would be either incapable of enduring so immoderate a light, or, were their eyes sufficiently strong, of receiving it unless they were at some distance; therefore the sun could only be a habitation for people without sight. In short, we have abundant proofs that this luminary was not intended to be a dwelling-place; and therefore we may as well continue our planetary journey. We are now stopping at the central point which is always the lowest part in any thing that is round; and, by the way, I should tell you that in going from our world to this centre we have travelled thirty-three millions of leagues. We must now return the way we came. We pass by Mercury, Venus, the Earth and the Moon; all which we have visited. Then we arrive at Mars. I don't know that there is any thing remarkable in this planet. The days there are about half an hour longer than ours; and the years twice the length of ours, except a month and a half. Mars is four times less than the earth,[37] and the sun appears rather smaller and less brilliant than it does to us.—In short, Mars contains nothing calculated to arrest our attention.

[37] Its volume, or bulk is five times smaller.

But what a beautiful object is Jupiter, surrounded by his four moons, or satellites! These moons are four little planets which, whilst Jupiter revolves in twelve years round the sun, constantly go round him as the moon does round the earth. But, interrupted the Marchioness, how is it that there are planets which go round other planets, no better than themselves? It seems to me that there would be much more regularity and uniformity in assigning to all the planets but one sort of orbit in which they should move round the sun.

Ah! madam, I replied, were you but acquainted with the vortices of Descartes; those vortices, so terrible in name, and so charming in the ideas they give rise to; you would not talk in this way. My wits must all go, said she, laughing. I must know what these vortices are. Make me quite mad at once: now I have dipped into philosophy I can't trouble myself about the care of my senses: spite of the world's laughter, we will talk of the vortices. I did not know you had so much enthusiasm, said I; 'tis pity it has no other object than vortices.