Monthly Archives: March 2019

Last Days of Earth

An extract from J.B.S.Haldane’s 1927 essay “The Last Judgement”:

The account given here will be broadcast to infants on the planet Venus some forty million years hence.
It has been rendered very freely into English, as many of the elementary ideas of our descendants will be beyond our grasp :

‘ It is now certain that human life on the earth’s surface is extinct, and quite probable that no living thing whatever remains there. The following is a brief record of the events which led up to the destruction of the ancient home of our species.
‘ Eighteen hundred and seventy-four million years ago the sun passed very close to the giant star 318.47.19543. The tidal wave raised by it in our sun broke into an incandescent spray. The drops of this spray formed the planets, of all of which the earth rotated by far the most rapidly. The earth’s year was then only very slightly shorter than now; but there were 1800 days in it, each lasting only a fifth of the time taken by a day when men appeared on earth. The liquid earth spun round for a few years as a spheroid greatly expanded at the equator and flattened at the poles by its excessive rotation. Then the tidal waves raised in it by the sun became larger and larger. Finally the crest of one of these waves flew off as the moon. At first the moon was very close to the earth, and the month was only a little longer than the day.
‘ As the moon raised large tides in the still liquid earth the latter was slowed down by their braking action, for all the work of raising the tides is done at the expense of the earth’s rotation. But by acting as a brake on the earth, the moon was pushed forward along its course, as any brake is pushed by the wheel that it slows down. As it acquired more speed it rose gradually farther and farther away from the earth, which had now a solid crust, and the month, like the day, became longer. When life began on the earth the moon was already distant, and during the sixteen hundred million years before man appeared it had only moved away to a moderate degree farther.
‘ When these distances were first measured by men the moon revolved in twenty-nine days, and the braking action of the tides amounted to twenty thousand million horse-power on the average. It is said that the effect of tidal friction in slowing down the earth’s rotation, and therefore lengthening the day, was first discovered by George Darwin, a son of Charles Darwin, who gave the earliest satisfactory account of evolution. However, there is reason to believe that both these personages are among the mythical culture-heroes of early human history, like Moses, Lao-Tze, Jesus, and Newton.
‘ At this time the effect of tidal friction was to make each century, measured in days, just under a second shorter than the last. The friction occurred mainly in the Bering Sea between northern Asia and America. As soon as the use of heat engines was discovered, man began to oxidize the fossil vegetables to be found under the earth’s surface. After a few centuries they gave out, and other sources of energy were employed. The power available from fresh water was small, from winds intermittent, and that from the sun’s heat only available with ease in the tropics. The tides were therefore employed, and gradually became the main source of energy. The invention of synthetic food led to a great increase in the world’s population, and after the federation of the world it settled down at about twelve thousand million. As tide engines were developed, an ever increasing use was made of their power ; and before the human race had been in existence for a million years, the tide-power utilized aggregated a million million horsepower. The braking action of the tides was increased fiftyfold, and the day began to lengthen appreciably.
‘ At its natural rate of slowing fifty thousand million years would have elapsed before the day became as long as the month, but it was characteristic of the dwellers on earth that they never looked more than a million years ahead, and the amount of energy available was ridiculously squandered. By the year five million the human race had reached equilibrium ; it was perfectly adjusted to its environment, the life of the individual was about three thousand years ; and the individuals were “ happy,” that is to say, they lived in accordance with instincts which were gratified. The tidal energy available was now fifty million million horse-power. Large parts of the planet were artificially heated. The continents were remodelled, but human effort was chiefly devoted to the development of personal relationships and to art and music, that is to say, the production of objects, sounds, and patterns of events gratifying to the individual.
‘ Human evolution had ceased. Natural selection had been abolished, and the slow changes due to other causes were traced to their sources and prevented before very great effects had been produced. It is true that some organs found in primitive man, such as the teeth (hard, bone-like structures in the mouth), had disappeared. But largely on aesthetic grounds the human form was not allowed to vary greatly. The instinctive and traditional preferences of the individual, which were still allowed to influence mating, caused a certain standard body form to be preserved. The almost complete abolition of the pain sense which was carried out before the year five million was the most striking piece of artificial evolution accomplished. For us, who do not regard the individual as an end in itself, the value of this step is questionable.
‘ Scientific discovery was largely a thing of the past, and men of a scientific bent devoted themselves to the more intricate problems of mathematics, organic chemistry, or the biology of animals and plants, with little or no regard for practical results. Science and art were blended in the practice of horticulture, and the effort expended on the evolution of beautiful flowers would have served to alter the human race profoundly. But evolution is a process more pleasant to direct than to undergo.
‘ By the year eight million the length of the day had doubled, the moon’s distance had increased by twenty per cent., and the month was a third longer than it had been when first measured. It was realized that the earth’s rotation would now diminish rapidly, and a few men began to look ahead, and to suggest the colonization of other planets. The older expeditions had all been failures. The projectiles sent out from the earth had mostly been destroyed by air friction, or by meteorites in interstellar space, and those which had reached the moon intact had generally been smashed by their impact on landing. Two expeditions had landed there with oxygen supplies, successfully mapped the face of it which is turned away from the earth, and signalled their results back. But return was impossible, and their members had died on the moon. The projectiles used in the earlier expeditions were metal cylinders ten metres or less in diameter and fifty or more in length. They were dispatched from vertical metal tubes several kilometres in length, of which the lower part was imbedded below the earth, while the upper projected. In order to avoid atmospheric resistance these tubes were generally built in high mountains, so that when the projectile emerged it had relatively little air to go through. The air in the tube itself was evacuated and a lid on the top removed as the projectile arrived. It was started off by a series of mild explosions which served to give it a muzzle velocity of about five kilometres per second without causing too great a shock. When it had left the lower atmosphere it progressed on the rocket principle, being impelled forward by the explosion of charges in its tail. The empty sections of the tail were also blown backward as required. It could be turned from inside by rotating a motor, or by the crew walking round.
‘ On arriving in the gravitational field of another planet its fall could be slowed by the discharge downward of more of its explosive cargo, and to check the final part of its fall various types of resistance were employed, and collapsible metal rods were extruded to break the shock of landing. Nevertheless, landing was generally fatal. As is well known, different principles are now employed. In particular, on leaving the atmosphere, wings of metallic foil of a square kilometre or more in area are spread out to catch the sun’s radiation pressure, and voyages are thus made on principles analogous to those employed in the ancient sailing-ships.
‘ The desire for individual happiness, and the fact that it was achieved on earth, made membership of such expeditions unpopular. The volunteers, who were practically committing suicide, were almost all persons whose mates had died prematurely, or whose psychology was for some reason so abnormal as to render them incapable of happiness. An expedition reached Mars successfully in the year 9,723,841, but reported that colonization was impracticable. The species dominant on that planet, which conducts its irrigation, are blind to those radiations which we perceive as light, and probably unaware of the existence of other planets ; but they appear to possess senses unlike our own, and were able to annihilate this expedition and the only other which reached Mars successfully.
‘ Half a million years later the first successful landing was effected on Venus, but its members ultimately perished owing to the unfavourable temperature conditions and the shortage of oxygen in its atmosphere. After this such expeditions became rarer.
‘ In the year 17,846,151 the tide machines had done the first half of their destructive work. The day and the month were now of the same length. For millions of centuries the moon had always turned the same face to the earth, and now the earth dwellers could only see the moon from one of their hemispheres. It hung permanently in the sky above the remains of the old continent of America. The day now lasted for forty eight of the old days, so that there were only seven and a half days in the year. As the day lengthened the climate altered enormously. The long nights were intensely cold, and the cold was generally balanced by high temperatures during the day. But there were exceptions.
‘ Mankind had appeared on earth during a period characterized by high mountains and recurrent ice-ages. Mountain-building had indeed almost ceased, though some ranges and many volcanoes appeared during man’s early life. But four ice-ages occurred shortly before history began, and a fifth had devastated parts of the northern continents during the second hundred thousand years of history. The ice had, however, been kept within relatively narrow limits by human endeavour. After the end of this period a huge co-operative effort of the human species had destroyed the remaining icefields. About the year 220,000 the ice-cap of Greenland had been gradually melted by the application of tidal energy, and soon after this the Arctic Ocean had become permanently ice-free. Later the Antarctic Continent had been similarly treated. Through most of the first half of human history there was therefore no permanent ice or snow save on a few mountains. The climate throughout the earth became relatively mild and uniform, as it had been through most of the time recorded by geology.
‘ But as the earth’s rotation slowed down, its equator contracted, causing earthquakes and mountain-building on a large scale. A good deal of land emerged from the oceans, especially the central Pacific. And with the lengthening of the nights snow began to be deposited on the uplands in fairly large amounts ; near the poles the sun occasionally failed to melt it during the day, and even where it was melted the subsoil was often permanently frozen. In spite of considerable efforts, icefields and giant glaciers had already appeared when the moon ceased to rise and set. Above them permanent anti-cyclones once more produced storms in the temperate regions, and rainless deserts in the tropics. The animals and plants only partially adapted themselves to the huge fluctuations of temperature. Practically all the undomesticated mammals, birds, and reptiles became extinct. Many of the smaller plants went through their whole life-cycle in a day, surviving only as seeds during the night. But most of the trees became extinct except when kept warm artificially.
‘ The human race somewhat diminished in numbers, but there was still an immense demand for power for heating and cooling purposes. The tides raised by the sun, although they only occurred fifteen times per year, were used for these ends, and the day was thus still further lengthened.
‘ The moon now began once more to move relative to the earth, but in the opposite direction, rising in the west and setting in the east. Very gradually at first, but then with ever-increasing speed, it began to approach the earth again, and appear larger. By the year 25,000,000 it had returned to the distance at which it was when man had first evolved, and it was realized that its end, and possibly the earth’s, were only a few million years ahead. But the vast majority of mankind contemplated the death of their species with less aversion than their own, and no effective measures were taken to forestall the approaching doom.
‘ For the human race on earth was never greatly influenced by an envisaged future. After physiology was discovered primitive men long continued to eat and drink substances which they knew would shorten and spoil their lives. Mineral fuels were also oxidized without much forethought. The less pigmented of the primitive races exhausted the fuel under the continents on which they lived with such speed that for some centuries the planet was dominated by the yellow variety resident in eastern Asia, where mining had developed more slowly ; until they too had exhausted their fuel resources. The unpigmented men appear to have foreseen this event, but did little or nothing to prevent it, even when it was clearly only a few generations ahead. Yet they had before them the history of an island in the North Atlantic on which Newton and Darwin are said to have lived, and whose inhabitants were the first to extract mineral fuel and the first to exhaust it, after which they disappeared from the stage of history, although at one time they had controlled large portions of the earth’s land surface.
‘ On the contrary, the earth’s inhabitants were often influenced in a curious way by events in the past. The early religions all attached great significance to such occurrences. If our own minds dwell more readily on the future, it is due largely to education and daily propaganda, but partly to the presence in our nuclei of genes such as H 149 and P 783 c, which determine certain features of cerebral organization that had no analogy on earth. For this reason we have undertaken the immense labour necessary to tap the central heat of our planet, rather than diminish its rotation. Even now this process involves a certain annual loss of life, and this was very much greater at first, so much so as to forbid its imitation on the earth, whose inhabitants generally valued their own lives and one another’s.
‘ But if most men failed to look ahead, a minority felt otherwise, and expeditions to Venus became commoner. After 284 consecutive failures a landing was established, and before its members died they were able to furnish the first really precise reports as to conditions on that planet. Owing to the opaque character of our atmosphere, the light signals of the earlier expeditions had been difficult to pick up. Infra-red radiation which can penetrate our clouds was now employed.
‘ A few hundred thousand of the human race, from some of whom we are descended, determined that though men died, man should live for ever. It was only possible for humanity to establish itself on Venus if it were able to withstand the heat and want of oxygen there prevailing, and this could only be done by a deliberate evolution in that direction first accomplished on earth. Enough was known of the causes responsible for evolution to render the experiment possible. The human material was selected in each generation. All who were not willing were able to resign from participation, and among those whose descendants were destined for the conquest of Venus a tradition and an inheritable psychological disposition grew up such as had not been known on earth for twenty-five million years. The psychological types which had been common among the saints and soldiers of early history were revived. Confronted once more with an ideal as high as that of religion, but more rational, a task as concrete as and infinitely greater than that of the patriot, man became once more capable of self-transcendence. Those members of mankind who were once more evolving were not happy. They were out of harmony with their surroundings. Disease and crime reappeared among them. For disease is only a failure of bodily function to adjust itself to the environment, and crime a similar failure in behaviour. But disease and crime, as much as heroism and martyrdom, are part of the price which must be paid for evolution. The price is paid by the individual, and the gain is to the race. Among ourselves an individual may not consider his own interests a dozen times in his life. To our ancestors, fresh from the pursuit of individual happiness, the price must often have seemed too great, and in every generation many who have now left no descendants refused to pay it.
‘ The modes of behaviour which our ancestors gradually overcame, and which only recur as the rarest aberrations among ourselves, included not only such self-regarding sentiments as pride and a personal preference concerning mating. They embraced emotions such as pity (an unpleasant feeling aroused by the suffering of other individuals). In a life completely dedicated to membership of a super-organism the one is as superfluous as the other, though altruism found its place in the emotional basis of the far looser type of society prevalent on earth.
‘ In the course of ten thousand years a race had been evolved capable of life at one-tenth of the oxygen pressure prevalent on earth, and the body temperature had been raised by six degrees. The rise to a still higher temperature, correlated as it was with profound chemical and structural changes in the body, was a much slower process. Projectiles of a far larger size were dispatched to Venus. Of 1734, only 11 made satisfactory landings. The crews of the first two of these ultimately perished ; those of the next eight were our ancestors. The organisms found on Venus were built of molecules which were mostly mirror images of those found in terrestrial bodies. Except as sources of fat they were therefore useless for food, and some of them were a serious menace. The third projectile to arrive included bacteria which had been synthesized on earth to attack 1-glucose and certain other components of the organisms on Venus. Ten thousand years of laboratory work had gone to their making. With their aid the previous life on that planet was destroyed, and it became available for the use of man and the sixty terrestrial species which he had brought with him.
‘ The history of our planet need not be given here. After the immense efforts of the first colonizers, we have settled down as members of a super-organism with no limits to its possible progress. The evolution of the individual has been brought under complete social control, and besides enormously enhanced intellectual powers we possess two new senses. The one enables us to apprehend radiation of wave-lengths between 100 and 1200 metres, and thus places every individual at all moments of life, both asleep and awake, under the influence of the voice of the community. It is difficult to see how else we could have achieved as complete a solidarity as has been possible. We can never close our consciousness to those wave-lengths on which we are told of our nature as components of a super-organism or deity, possibly the only one in spacetime, and of its past, present, and future. It appears that on earth the psychological equivalent of what is transmitted on these wave-lengths included the higher forms of art, music, and literature, the individual moral consciousness, and, in the early days of mankind, religion and patriotism. The other wave-lengths inform us of matters which are not the concern of all at all times, and we can shut them out if we so desire.
‘ Their function is not essentially different from that of instrumental radio-communication on earth. The new magnetic sense is of less importance, but is of value in flying and otherwise in view of the very opaque character of our atmosphere. It would have been almost superfluous on earth. We have also recovered the pain sense, which had become vestigial on earth, but is of value for the survival of the individual under adverse circumstances, and hence to the race. So rapid was our evolution that the crew of the last projectile to reach Venus were incapable of fertile unions with our inhabitants, and they were therefore used for experimental purposes.
‘ During the last few million years the moon approached the earth rather rapidly. When it became clear that the final catastrophe could not be long delayed the use of tide-power was largely discontinued, according to the signals which reached us from the earth, and wind and other sources of power were substituted. But the earth-dwellers were sceptical as to whether the approaching rupture of the moon would entail their destruction, and the spin of the earth-moon system was still used to some-extent as a source of power. In the year 36,000,000 the moon was at only a fifth of its distance from the earth when history had begun. It appeared twenty-five times as large as the sun, and raised the sea-level by some 200 metres about four times a year. The effects of the tidal strain raised in it by the earth began to tell. Giant landslips were observed in the lunar mountains, and cracks occasionally opened in its surface. Earthquakes also became rather frequent on the earth.
‘ Finally the moon began to disintegrate. It was so near to the earth as to cover about a twentieth of the visible heavens when the first fragments of rock actually left its surface. The portion nearest to the earth, already extensively cracked, began to fly away in the form of meteorites up to a kilometre in diameter, which revolved round the earth in independent orbits. For about a thousand years this process continued gradually, and finally ceased to arouse interest on the earth. The end came quite suddenly. It was watched from Venus, but the earlier stages were also signalled from the earth. The depression in the moon’s surface facing the earth suddenly opened and emitted a torrent of white-hot lava. As the moon passed round the earth it raised the temperature in the tropics to such an extent that rivers and lakes were dried up and vegetation destroyed.
‘ The colour changes on earth due to the flowering of the plants which were grown on it for the pleasure of the human race, and which were quite visible from our planet, no longer occurred. Dense clouds were formed and gave some protection to the earth. But above them the sea of flame on the moon increased in magnitude, and erupted in immense filaments under the earth’s gravitation. Within three days the satellite had broken up into a ring of white-hot lava and dust. The last message received from the earth stated that the entire human race had retired underground, except on the Antarctic Continent, where however the ice-cap had already melted and the air temperature was 35 C. Within a day from the moon’s break-up the first large fragment of it had fallen on the earth. The particles formed from it were continually jostling, and many more were subsequently driven down. Through the clouds of steam and volcanic smoke which shrouded the earth our astronomers could see but little , but later on it became clear that its tropical regions had been buried many kilometres deep under lunar fragments, and the remainder, though some traces of the former continents remain, had been submerged in the boiling ocean. It is not considered possible that any vestige of human life remains, nor can our spectroscopes detect any absorption bands of chlorophyll which would indicate the survival of plants.
‘ The majority of the lunar matter has formed a ring round the earth, like those of Saturn, but far denser. It is not yet in equilibrium, and fragments will continue to fall on the earth for about another thirty-five thousand years. At the end of that period the earth, which now possesses a belt of enormous mountains in its tropical regions, separated from the poles by two rings of sea, will be ready for recolonization. Preparations are being made for this event. We have largely sorted out the useful elements in the outer five kilometres or so of our planet, and it is proposed, when the earth is reoccupied, to erect artificial mountains on both planets which will extend above the Heaviside layer and enable continuous radio-communication instead of light signals to be used between the two.
‘ The old human race successfully cultivated individual happiness and has been destroyed by fire from heaven. This is not a cause for great regret, since happiness does not summate. The happiness of ten million individuals is not a millionfold the happiness of ten. But the unanimous co-operation of ten million individuals is something beyond their individual behaviour. It is the life of a super-organism. If, as many of the earthdwellers hoped, the moon had broken up quietly, their species might have lasted a thousand million years instead of thirty-nine million, but their achievement would have been no greater.
‘ From the earth it is proposed to colonize Jupiter. It is not certain that the attempt will succeed, for the surface temperature of that planet is -130 degrees C., gravitation is three times as intense as that on Venus, and over twice that on earth, while the atmosphere contains appreciable quantities of thoron, a radioactive gas. The intense gravitation would of course destroy bodies as large as our own, but life on Jupiter will be possible for organisms built on a much smaller scale. A dwarf form of the human race about a tenth of our height, and with short stumpy legs but very thick bones, is therefore being bred. Their internal organs will also be very solidly built. They are selected by spinning them round in centrifuges which supply an artificial gravitational field, and destroy the less suitable members of each generation. Adaptation to such intense cold as that on Jupiter is impracticable, but it is proposed to send projectiles of a kilometre in length, which will contain sufficient stores of energy to last their inhabitants for some centuries, during which they may be able to develop the sources available on that planet. It is hoped that as many as one in a thousand of these projectiles may arrive safely. If Jupiter is successfully occupied the outer planets will then be attempted.
‘ About 250 million years hence our solar system will pass into a region of space in which stars are far denser than in our present neighbourhood. Although not more than one in ten thousand is likely to possess planets suitable for colonization.it is considered possible that we may pass near enough to one so equipped to allow an attempt at landing. If by that time the entire matter of the planets of our system is under conscious control, the attempt will stand some chance of success. Whereas the best time between the earth and Venus was one-tenth of a terrestrial year, the time taken to reach another stellar system would be measured in hundreds or thousands of years, and only a very few projectiles per million would arrive safely. But in such a case waste of life is as inevitable as in the seeding of a plant or the discharge of spermatozoa or pollen. Moreover, it is possible that under the conditions of life in the outer planets the human brain may alter in such a way as to open up possibilities inconceivable to our own minds. Our galaxy has a probable life of at least eighty million million years. Before that time has elapsed it is our ideal that all the matter in it available for life should be within the power of the heirs of the species whose original home has just been destroyed. If that ideal is even approximately fulfilled, the end of the world which we have just witnessed was an episode of entirely negligible importance. And there are other galaxies.’