Dreams of an astronomer

by Camille Flammarion

(1) TWO HUNDRED AND FORTY THOUSAND MILES FROM THE EARTH

I seemed to approach the pale Phœbe and to arrive suddenly above the immense chain of the lunar Apennines, which separate the “Sea of Vapour” from the “Sea of Rain,” not far from the central meridian. I recognised, just as I had so often observed them in the telescope, the amphitheatres and craters of Archimedes, Autolycus, and Aristillus, and I hovered for some time over the steep cliffs of the “Sea of Serenity.” I saw the traces of old submersions and I distinguished several craters almost obliterated by formidable land-slides. I got accustomed to this view the more rapidly for the fact that astronomical instruments have long familiarised us with this neighbouring world, and that certain details of lunar geography are better known than are many points of terrestrial geography. Those immense amphitheatres, those yawning craters, those steep-walled mountains, those deep valleys, those numerous cracks in the soil—we have studied them all and we know them. We find there the geographical result of considerable volcanic activity, craters 2 miles in depth and 60, 100, or 150 miles wide, mountain peaks 4 or 5 miles high, plains and valleys where the traces of successive selenological epochs are traceable. In the lower depths I observed the effects of a sensible atmosphere, surface changes produced over immense stretches of ground by the action of the Sun’s rays during days fifteen times as long as ours, changes of aspect due to the frost of the long lunar night and the thaw under the midday Sun, long white streaks traversing the circular plains; something like geysers in activity; short-lived plants without any terrestrial analogy—a whole world still alive, apparently in its last death-struggle. My thought and my gaze rested on the pale figure of the Earth’s satellite, and I asked myself whether there was not alive at that moment, in some ancient city at the bottom of a crater or a valley, some thinking being, with its eyes raised to the sky, contemplating the Earth where we are and asking the same question: whether any intelligent beings lived on the surface of that immense globe throning for ever over their heads, and presenting to their minds the same riddle which their abode presents to us.

While I thus reflected about our neighbour in space, the orb of night had sunk in the west, and I saw at some distance from it on the left a star shining with a reddish glow, shedding rays of fire over the heavenly vault. I was not long in recognising in this ardent star our neighbour the planet Mars, and I forgot the moon over this other celestial island, the sister of our own, which has so many analogies with our planet.

Here, said I to myself, is the planet of greatest interest to ourselves, the one we know best. It gravitates round the sun along an orbit traced at a mean distance of 143 million miles from the central luminary. Our Earth passes through its annual revolution at a distance of 92 million miles. There are, therefore, on an average, 51 million miles between the two orbits. On the night of my vigil, Mars happened to be at its minimum distance from the Earth. Fortunately, as the two orbits are neither circular nor parallel, the real distance is sometimes reduced to 37 million miles. Light, which takes 1⅓ second to traverse the distance between the Earth and the Moon, takes 200 seconds, or 3 minutes 20 seconds, to cross the celestial abyss which separates Mars from the Earth, It seemed to me that I really spent those 3 minutes in flying the distance, and I entirely forgot the high window of my Venetian palace over the aspect of the new world to which the flight of my thought had brought me.

(2) THIRTY-SEVEN MILLION MILES PROM THE EARTH

It is not very far, astronomically speaking. It is, in fact, quite near, a few paces away. The world of Mars is the first station of the solar system, the first planet we meet on leaving the Earth to visit the remote regions of the heavens. The farther we move away from the Earth, the smaller grows the apparent size of our own world. Seen from the Moon, our planet hangs in the sky like an enormous moon, four times the size of our own satellite, and sixteen times as luminous, for it is isolated in space and reflects the light received from the Sun, as is done by the Moon and the various planets of the solar system. From about 250,000 miles, therefore, the Earth still appears of a considerable size, being about four times the size of the full Moon. At 2½ million miles it appears ten times smaller in diameter, but still shows a perceptible disc. At the distance of the orbit of Mars, at the time when the planets are in greatest proximity (37 million miles), the Earth no longer shows a sensible disc, but is still the biggest and brightest star in the entire heavens. The inhabitants of Mars, therefore, admire us as a brilliant star in the sky, showing aspects similar to those which Venus shows to us. We are their morning and evening star, and no doubt their mythology has erected altars to us.

When I arrived on that planet, it was about midday on its central meridian. I noticed two small moons revolving rapidly in their sky, and I alighted on the slope of a mountain overlooking a distant sea. The sea was shallow and full of water-plants. The panorama reminded me of that which one sees from the terrace of the Nice Observatory, and I seemed to see a Mediterranean of calm water, of a rather dark bluish-green colour. But it was a different element, and I saw that the plants were of a species unknown on Earth. Airy navies consisting of a sort of bird-fishes glided through the atmosphere, and I soon found that the inhabitants of this celestial territory have received by natural evolution the enviable privilege of flying through the air, and that their method of locomotion is particularly aviation. Gravity is feeble on the surface of the planet, and hence the density of beings and objects on that planet is much less than it is with us. Engineering science has for many centuries reached a high degree of perfection. They have carried out immense works, incomparably superior to those achieved on our planet during the last century, and they have transformed their globe by gigantic operations which earthly astronomers are just beginning to appreciate by means of the telescope. One may easily understand, indeed, that that world should be more advanced than ours, because it is more ancient chronologically, and because, being smaller than our globe, it has cooled down more rapidly and has run through the phases of organic evolution at a greater rate. Its years are nearly twice as long as ours, in the proportion of 365 days to 687. While we count 37 years on Earth, the Martian only counts 20, and a man of 79 years on Earth is only 40 Martian years old. This is an advantage of 88 per cent. Its condition of habitability, its climate and meteorology, its days and its nights, are analogous to ours. Even from where we are we can observe its continents, its polar snows which melt in the spring, its canals which also change with the seasons, its humid plains periodically varied by vegetation, its clouds, generally very light, but dense enough towards the polar regions, its mists in the mornings and especially in the evening, above all, the perpetual changes, incomparably more intense than those of the Earths surface—in a word, all those manifestations of an activity greater than that of our own home of the present day.

I only delayed on Mars for the time necessary to form a general idea of the life which animates our neighbouring globe and to make sure that it is more active than that of terrestrial humanity, and I found myself, some moments later, transported to the annular world of Saturn.

(3) AT SEVEN HUNDRED AND FIFTY MILLION MILES

The conception of time, the appreciation of duration, are essentially relative to the state of our mind. If we sleep profoundly for seven or eight hours, that time will have made a gap in our life of no greater length than that produced by ten minutes of sleep. The miners who by the collapse of a shaft are entombed for five or six days before being rescued, always believe that they have not been cut off for more than twenty hours. Buried on a Tuesday, for instance, they will not believe that they have had to wait till Sunday. On the other hand, one may seem to pass several hours, very slowly, in a dream of a few seconds. A friend of mine told me that one day, as he was riding through a wood, his horse bolted and threw him into a ravine. He said his fall had certainly not taken more than three seconds, but that during those three seconds he had passed in review at least ten years of his life in all their successive details and without any apparent hurrying of events. Then, again, who has not observed how long the minutes may seem during some hours of waiting?