Astronomy for Amateurs - Camille Flammarion (ebook reader with android os TXT) 📗

Yes, thanks to us, the inhabitants of the lunar hemisphere turned toward us are gratified by the sight of a splendid nocturnal torch, doubtless less white than our own despite the clouds with which the terrestrial globe is studded, and shaded in a tender tone of bluish emerald-green. The royal orb of their long nights, the Earth, gives them moonlight of unparalleled beauty, and we may say without false modesty that our presence in the lunar sky must produce marvelous and absolutely fairy-like effects.

Maybe, they envy us our globe, a dazzling dwelling-place whose splendor radiates through space; they see its greenish clarity varying with the extent of cloud that veils its seas and continents, and they observe its motion of rotation, by which all the countries of our planet are revealed in succession to its admirers.

We are talking of these pageants seen from the Moon, and of the inhabitants of our satellite as if they really existed. The sterile and desolate aspect of the lunar world, however, rather brings us to the conclusion that such inhabitants are non-existent, although we have no authorization for affirming this. That they have existed seems to me beyond doubt. The lunar volcanoes had a considerable activity, in an atmosphere that allowed the white volcanic ashes to be carried a long way by the winds, figuring round the craters the stellar rays that are still so striking. These cinders were spread over the soil, preserving all its asperities of outline, a little heaped up on the side to which they were impelled. The magnificent photographs recently made at the Paris Observatory by MM. Loewy and Puiseux are splendid evidence of these projections. In this era of planetary activity there were liquids and gases on the surface of the lunar globe, which appear subsequently to have been entirely absorbed. Now the teaching of our own planet is that Nature nowhere remains infertile, and that the production of Life is a law so general and so imperious that life develops at its own expense, sooner than abstain from developing. Accordingly, it is difficult to suppose that the lunar elements can have remained inactive, when only next door they exhibited such fecundity upon our globe. Yes, the Moon has been inhabited by beings doubtless very different from ourselves, and perhaps may still be, although this globe has run through the phases of its astral life more rapidly than our own, and the daughter is relatively older than the mother.

The duration of the life of the worlds appears to have been in proportion with their masses. The Moon cooled and mineralized more quickly than the Earth. Jupiter is still fluid.

The progress of optics brings us already very close to this neighboring province. 'Tis a pity we can not get a little nearer!

A telescopic magnification of 2,000 puts the Moon at 384,000⁄2,000 or 192 kilometers (some 120 miles) from our eye. Practically we can obtain no more, either from the most powerful instruments, or from photographic enlargements. Sometimes, exceptionally, enlargements of 3,000 can be used. This = 384,000⁄3,000 or 128 kilometers (some 80 miles). Undoubtedly, this is an admirable result, which does the greatest honor to human intelligence. But it is still too far to enable us to determine anything in regard to lunar life.

Any one who likes to be impressed by grand and magnificent sights may turn even a modest field-glass upon our luminous satellite, at about first quarter, when the relief of its surface, illuminated obliquely by the Sun, is at its greatest value. If you examine our neighbor world at this period, for choice at the hour of sunset, you will be astonished at its brilliancy and beauty. Its outlines, its laces, and embroideries, give the image of a jewel of shining silver, translucent, fluid, palpitating in the ether. Nothing could be more beautiful, nothing purer, and more celestial, than this lunar globe floating in the silence of space, and sending back to us as in some fairy dream the solar illumination that floods it. But yesterday I received the same impression, watching a great ring half standing out, and following the progress of the Sun as it mounted the lunar horizon to touch these silvered peaks. And I reflected that it is indeed inconceivable that 999,999⁄1,000,000 of the inhabitants of our planet should pass their lives without ever having attended to this pageant, nor to any of those others which the divine Urania scatters so profusely beneath the wondering gaze of the observers of the Heavens.

Among all the celestial phenomena at which it may be our lot to assist during our contemplation of the universe, one of the most magnificent and imposing is undoubtedly that which we are now going to consider.

The hirsute comets, and shooting stars with their graceful flight, captivate us with a mysterious and sometimes fantastic attraction. We gladly allow our thoughts, mute questioners of the mysteries of the firmament, to rest upon the brilliant, golden trail they leave behind them. These unknown travelers bring a message from eternity; they tell us the tale of their distant journeys. Children of space, their ethereal beauty speaks of the immensity of the universe.

The eclipses, on the other hand, are phenomena that touch us more nearly, and take place in our vicinity.

In treating of them, we remain between the Earth and the Moon, in our little province, and witness the picturesque effects of the combined movements of our satellite around us.

Have you ever seen a total eclipse of the Sun?

The sky is absolutely clear: no fraction of cloud shadows the solar rays. The azure vault of the firmament crowns the Earth with a dome of dazzling light. The fires of the orb of day shed their beneficent influence generally upon the world.

Yet, see! The radiance diminishes. The luminous disk of the Sun is gradually corroded. Another disk, as black as ink, creeps in front of it, and little by little invades it entirely. The atmosphere takes on a wan, sepulchral hue; astonished nature is hushed in profound silence; an immense veil of sadness spreads over the world. Night comes on suddenly, and the stars shine out in the Heavens. It seems as though by some mysterious cataclysm the Sun had disappeared forever. But this tribulation is soon over. The divine orb is not extinct. A flaming jet emerges from the shadow, announcing his return, and when he reappears we see that he has lost nothing in splendor or beauty. He is still the radiant Apollo, King of Day, watching over the life of the planetary worlds.

This sudden night, darkening the Heavens in the midst of a fine day, can not fail to produce a vivid impression upon the spectators of the superb phenomenon.

The eclipse lasts only for a few moments, but long enough to make a deep impression upon our minds, and indeed to inspire anxious spirits with terror and agitation—even at this epoch, when we know that there is nothing supernatural or formidable about it.

In former days, Humanity would have trembled, in uneasy consternation. Was it a judgment from Heaven? Must it not be the work of some invisible hand throwing the somber veil of night over the celestial torch?

Had not the Earth strayed off her appointed path, and were we not all to be deprived eternally of the light of our good Sun? Was some monstrous dragon perhaps preparing to devour the orb of day?

The fable of the dragon devouring the Sun or Moon during the eclipses is universal in Asia as in Africa, and still finds acceptance under more than one latitude. But our readers already know that we may identify the terrible celestial dragon with our gentle friend the Moon, who would not be greatly flattered by the comparison.

We saw in the preceding lesson that the Moon revolves round us, describing an almost circular orbit that she travels over in about a month. In consequence of this motion, the nocturnal orb is sometimes between the Sun and the Earth, sometimes behind us, sometimes at a right angle in relation to the Sun and the Earth. Now, the eclipses of the Sun occur invariably at the time of New Moon, when our satellite passes between the Sun and ourselves, and the eclipses of the Moon, at the moment of Full Moon, when the latter is opposite to the Sun, and behind us.

This fact soon enabled the astronomers of antiquity to discover the causes