Dreams of an astronomer

by Camille Flammarion

We should see the star shining steadily in the sky for four years after the catastrophe which had destroyed it, because light travels through space with a speed of 186,000 miles a second, and it would have to travel with this constant velocity more than four years before reaching us.

Seen from that distance, our brilliant Sun is reduced to the rank of a simple star. The planets which gravitate around it, the Earth, Venus, Mars, Jupiter, Saturn, and their brothers of the solar family, are crowded up against it by the perspective of the distance and are invisibly lost in its rays.

Considered at that distance in the sidereal universe, these provinces of the solar empire are recognised as insignificant even by the most optimistic spirit. Even if they did not exist at all, the suns of infinite space would none the less shed their rays of life and light all around. Our planet, which to us seems so important, becomes a microscopic point impossible to discover by means of senses such as ours, and its history told at that distance becomes like the flight of a dragon-fly or even less, since we should never suspect its existence if we did not know it. It is at such moments especially that the pretensions of Pontiffs and the dogmatic assurance of their adepts show forth in all their absurdity.

I felt transported into the system of that star, the nearest of all those whose distances have been measured, a star belonging to the constellation of the Centaur; it is the Alpha of that constellation. This system is curious and more interesting than ours. Instead of a single sun corresponding to that which shines upon us, two twin suns gravitate one round the other in a time equalling 81 of our years, and separated from each other by a distance of 2,000 million miles. These twin suns are both of considerable brightness (first and second magnitude, seen from here), and greatly superior to the central hearth of our own system. Planets circulate around each of these luminaries under their protecting wings, and receive from their radiation the sources of their fertility and their life. They are illuminated by two different suns, sometimes united in the same sky, sometimes separated and alternating, differing in magnitude and brightness according to the variation of the distances in consequence of the revolutions of these worlds round their respective centres.

These are very different conditions of existence from those which govern the destinies of the Earth and of the planets of our group. Two suns! What curious alternations of seasons! What variations in the climates! What transformations in the doubtlessly very rapid changes of their vitality! What complications of their calendars, in the succession of their years, their summers and winters, their days and nights! The sole fact of the existence of such a system, relatively near to us and already well-known to terrestrial astronomers, testifies to the infinite variety disseminated in the starry depths of the cosmos.

What multiplicity of manifestations of the diverse forces of nature must have been produced in this wealth of solar development—manifestations strange to the phenomena studied on our planet, and which are doubtlessly felt and appreciated by means of senses differing absolutely from those existing in terrestrial organisms, senses awakened, determined, and developed in those distant worlds by their own natural forces.

On worlds illuminated, heated, and regulated by two suns life can only have appeared and organised itself in forms very different from those on Earth, having no doubt an alternating double life, served by other modes of perception, other organs, and other senses. The thinker, the astronomer, the physiologist, can no longer regard terrestrial life as the type of all life. All we could learn, study, or know on Earth will never be more than an infinitesimal and absolutely insufficient part of the immense reality embodied in the innumerable creations of the Infinite.

Yet it is a point which must be insisted upon before pursuing our terrestrial investigations further, that whatever may be the variety of stellar systems, the differences of volume, temperature, density, illumination, electrification, movement, chemical constitution, etc., of the various globes which people the immensity of the universe, all these worlds are linked amongst themselves by the same invisible and imponderable Power which combines them all in a network of extreme sensitiveness. The prodigious extent of the distances which separate these systems one from the other does not prevent their being connected together by some sort of maternal link. The distance from the Earth to the Moon is 240,000 miles. The Moon acts constantly upon all the molecules of our globe and upon the entire Earth, and every one of us weighs a little less when that body shines over our heads than when it is on the horizon. The distance from the Sun to the Earth is 92 million miles; the Sun makes our planet move with a speed corresponding to that distance, and the Earth in its turn displaces the Sun in the heavens. The distance from the Sun to Neptune is over 2,500 million miles. The central globe acts upon that distant world and makes it revolve round it, and on the other hand Neptune makes the Sun revolve round their common centre of gravity, which is at a distance of 144,000 miles from the centre of the Sun. Jupiter displaces the Sun by 460,000 miles, and Saturn by 25,000 miles. The Moon disturbs the Earth to the extent of 2,900 miles. At the same time Jupiter acts upon the Earth, the Earth upon Venus, and so on. On account of this reciprocal influence of all the heavenly bodies upon each other, not a single point can remain in repose for an instant, and no heavenly body can ever come back to the place it previously occupied. All that we call matter is in perpetual motion under the irresistible power of invisible, intangible, and imponderable force.

We have here a fact of capital importance, the consideration of which must always be associated with the conception we can form of the real nature of the universe. We have seen just now that the distance which separates our Sun from the star Alpha Centauri is 25 billion miles. But this distance is traversed by gravitational attraction. In reality the two suns are not absolutely separated.

They know each other, they feel each other’s attraction, and they feel the attraction of all the other suns of infinite space. They both roam about, our own Sun with a speed calculated at about 200 million miles per annum and Alpha Centauri with a speed of approximately 400 million. The other suns of which we know the distance and the movement rush on with similar speeds. Some of them fly with incomparably greater velocities, which attain 200 miles a second, 11,000 miles per minute, 600,000 miles an hour, 15 million per day, and 5 or 6 thousand million miles per annum, veritable starry projectiles of the heavenly fields.