3. a minor astronomical event
The flightless yet still half avian race that now possessed the planet settled down to construct a society based on industry and science. After many vicissitudes of fortune and of aim, they produced a new human species, the Eighth Men. These long-headed and substantial folk were designed to be strictly pedestrian, physically and mentally. Apt for manipulation, calculation and invention, they very soon turned Venus into an engineer's paradise. With power drawn from the planet's central heat, their huge electric ships bored steadily through the perennial monsoons and hurricanes, which also their aircraft treated with contempt. Islands were joined by tunnels and by millepede bridges. Every inch of land served some industrial or agricultural end. So successfully did the generations amass wealth that their rival races and rival castes were able to indulge, every few centuries, in vast revelries of mutual slaughter and material destruction without, as a rule, impoverishing their descendants. And so insensitive had man become that these orgies shamed him not at all. Indeed, only by the ardours of physical violence could this most philistine species wrench itself for a while out of its complacency. Strife which to nobler beings would have been a grave spiritual disaster, was for these a tonic, almost a religious exercise. These cathartic paroxysms, it should be observed, were but the rare and brief crises which automatically punctuated ages of stolid peace. At no time did they threaten the existence of the species; seldom did they even destroy its civilization.
It was after a lengthy period of peace and scientific advancement that the Eighth Men made a startling astronomical discovery. Ever since the First Men had learned that in the life of every star there comes a critical moment when the great orb collapses, shrinking to a minute, dense grain with feeble radiation, man had periodically suspected that the sun was about to undergo this change, and become a typical "White Dwarf." The Eighth Men detected sure signs of the catastrophe, and predicted its date. Twenty thousand years they gave themselves before the change should begin. In another fifty thousand years, they guessed, Venus would probably be frozen and uninhabitable. The only hope was to migrate to Mercury during the great change, when that planet was already ceasing to be intolerably hot. It was necessary then to give Mercury an atmosphere, and to breed a new species which should be capable of adapting itself finally to a world of extreme cold.
This desperate operation was already on foot when a new astronomical discovery rendered it futile. Astronomers detected, some distance from the solar system, a volume of non-luminous gas. Calculation showed that this object and the sun were approaching one another at a tangent, and that they would collide, Further calculation revealed the probable results of this event. The sun would flare up and expand prodigiously. Life would be quite impossible on any of the planets save, just possibly, Uranus, and more probably Neptune. The three planets beyond Neptune would escape roasting, but were unsuitable for other reasons, The two outermost would remain glacial, and, moreover, lay beyond the range of the imperfect etherships of the Eighth Men. The innermost was practically a bald globe of iron, devoid not merely of atmosphere and water, but also of the normal covering of rock. Neptune alone might be able to support life; but how could even Neptune be populated? Not only was its atmosphere very unsuitable, and its gravitational pull such as to make man's body an intolerable burden, but also up to the time of the collision it would remain excessively cold. Not till after the collision could it support any kind of life known to man.
How these difficulties were overcome I have no time to tell, though the story of man's attack upon his final home is well worthy of recording, Nor can I tell in detail of the conflict of policy which now occurred, Some, realizing that the Eighth Men themselves could never live on Neptune, advocated an orgy of pleasure-living till the end, But at length the race excelled itself in an almost unanimous resolve to devote its remaining centuries to the production of a human being capable of carrying the torch of mentality into a new world.
Ether-vessels were able to reach that remote world and set up chemical changes for the improvement of the atmosphere. It was also possible, by means of the lately rediscovered process of automatic annihilation of matter, to produce a constant supply of energy for the warming of an area where life might hope to survive until the sun should be rejuvenated.
When at last the time for migration was approaching, a specially designed vegetation was shipped to Neptune and established in the warm area to fit it for man's use. Animals, it was decided, would be unnecessary. Subsequently a specially designed human species, the Ninth Men, was transported to man's new home. The giant Eighth Men could not themselves inhabit Neptune. The trouble was not merely that they could scarcely support their own weight, let alone walk, but that the atmospheric pressure on Neptune was unendurable. For the great planet bore a gaseous envelope thousands of miles deep. The solid globe was scarcely more than the yolk of a huge egg. The mass of the air itself combined with the mass of the solid to produce a gravitational pressure greater than that upon the Venerian ocean floor. The Eighth Men, therefore, dared not emerge from their ether-ships to tread the surface of the planet save for brief spells in steel diving suits, For them there was nothing else to do but to return to the archipelagos of Venus, and make the best of life until the end. They were not spared for long. A few centuries after the settlement of Neptune had been completed by transferring thither all the most precious material relics of humanity, the great planet itself narrowly missed collision with the dark stranger from space. Uranus and Jupiter were at the time well out of its track. Not so Saturn, which, a few years after Neptune's escape, was engulfed with all its rings and satellites. The sudden incandescence which resulted from this minor collision was but a prelude. The huge foreigner rushed on. Like a finger poked into a spider's web, it tangled up the planetary orbits. Having devoured its way through the asteroids, it missed Mars, caught Earth and Venus in its blazing hair, and leapt at the sun. Henceforth the centre of the solar system was a star nearly as wide as the old orbit of Mercury, and the system was transformed.