Monday, 27 July 2015

Photos & Quotes: The Exploration of the Moon (1954) by R. A. Smith and Arthur C. Clarke

London: Frederick Muller, 1954. 


At this embryonic stage of astronautics, we obviously cannot foresee every detail of the ships which will take the next generation beyond the atmosphere. We do, however, know enough to make some reasonable predictions, and - barring unforeseen discoveries - we know some of the intermediate steps that will have to be taken before manned space-flight is a reality. This book aims to give a visual presentation of these steps, from the launching of the first automatic missiles, through the techniques of refuelling in space, to the landing on the Moon and the first lunar colony. The Moon is only the nearest of heavenly bodies, and by no means the most important. But it will be proving ground for the explorers of the future; once it has been subjugated, the skills needed for the mastery of remoter worlds will have been acquired.


Many of these apparently far-fetched ideas seem more reasonable when presented by the artist, to whom space-flight presents an inspiring challenge. To describe in words such events as the refuelling of one rocket by another while both are circling the Earth is no easy task. Even when it is done, the general reader is liable to have a somewhat confused idea of the operation, because it deals with matters quite outside ordinary experience. It is believed, therefore, that this book will break new ground by presenting a detailed step-by-step visualisation of the first century of space-conquest.


This book falls into four parts, which may be likened to the phases of a military operation. Phase One - "On the Frontier of Space" - is concerned with the establishing of the first orbital rockets, circling the Earth just beyond the limits of the atmosphere. It will be shown how this is the essential first step in the conquest of space, for it will enable us to break down any interplanetary voyage into a number of stages. Without such a technique, we should be faced with the task of having to design impossibly large vessels capable of carrying fuel for the complete trip.

It may seem a little odd to stop and refuel after a mere hundred miles on a journey of perhaps millions. This is just another of the paradoxes of space-flight which will be examined in the course of this book.

When we have learned how to establish these satellite rockets, get them safely back, and transfer fuel between them, we will be ready to go further afield. Part Two, therefore, shows the events for which the world will then be waiting - the circling of the Moon by a robot vehicle, and the final descent of a man-made object upon our nearest neighbour in space.

Section Three describes the first landing, which will be followed by the most exciting - and perhaps the most heart-breaking - of all man's explorations. First a small temporary base, then permanent settlements will be established by engineering techniques which we can envisage today. At first they will be supplied from Earth, at an enormous cost in rocket fuel, but as soon as possible they will have to be made self-sufficient. The Moon must possess all the elements, and most of the minerals, that exist on Earth. The provision of air, water and ultimately food from lunar resources should therefore be perfectly practicable.

Section Four is concerned with remoter events, of whose probability we can say little at the present day. Until we know a great deal more about the Moon and its resources, we cannot be certain if the lunar settlement will ever grow into a fully-fledged colony, able to stand on its own feet and perhaps ultimately become independent of Earth. The answer of this question depends on technical factors quite as much as upon what may be called political ones.


But it is one thing to show how space-flight may be achieved; it is quite another to show why. When they see the enormous efforts which will have to be expended to install a few men on the Moon, a great many people will ask "Why should we bother about space-travel, when there is so much to be done on Earth? Can the human race afford it anyway?"

The last question can be answered very briefly. The total cost of the first lunar expedition, including non-recurring development and research, would be about a thousandth of the wealth squandered in the Second World War.... Yes, humanity can afford space-travel, if it really wants it.

Certainly there is a great deal still to do on Earth. However, even on the purely material level, space-flight will increase the resources - the real wealth - of mankind. It must never be forgotten that scientific research is the most profitable of all investments, though no one can tell in advance when the dividends will start to arrive.

But material considerations are not all-important. [...] The spirit of curiosity and wonder is the driving force behind all Man's achievements. If it ever fails, the story of our race will be coming to an end.

There will always be plenty of people who will stay at home and do the jobs their fathers did; without them, civilisation would not survive. Yet there must also be those who are never content with things as they are, who will not rest while any new horizons remain uncrossed. It is not safe to keep them at home: in their frustration, they will cause mischief. But let them go, and they will become the great explorers and discoverers, opening up new worlds of mind and matter for those who come after them.

They are the ones who, in the ages now opening before us, will lead the human race out of the nursery in which it has played for long enough. For no healthy society can stand still; a civilisation which has no problems, no challenge to try its strength, must eventually stagnate. It may be pleasant for the individual to dream of stability and the end of striving, but when a race seeks such things, its doom is already upon it.

On the Frontier of Space

Before human beings travel out into space, many flights beyond the atmosphere will be made by automatic rockets carrying instruments which can send information back to earth by radio. In this way, conditions in space will be well understood in advance, and the techniques for handling large rockets will be worked out before manned flights are risked.

1. Assembling Satellite Rocket.
The illustration shows a three-stage instrument-carrying rocket being fuelled and prepared for launching. The two lower stages - often called "boosters" - are finned and would drop back to Earth by parachute when their fuel is exhausted. Only the small uppermost step would achieve orbital speed and so remain forever in space, circling the Earth at a height of a few hundred miles.

2. Instrument-carrying Rocket in Orbit.
Here is the upper stage of the satellite rocket when it has completed its mission, perhaps two hundred miles above Earth. It can never fall down again - though not because it is "beyond the pull of gravity," for gravity at this altitude is practically as powerful as at sea-level. It stays up for exactly the same reason as the Moon does - because of its velocity. It is moving right round the Earth at such a speed that the downward pull of gravity precisely balances its tendency to fly out into space. Only if it lost speed could it fall down, and since there is no air-resistance it cannot do this. 

3. Mounting Winged Rocket on Booster.
After tests had been completed with unmanned robot missiles - or even while they they were still in progress - piloted rockets would be flown to the upper atmosphere and above. [...] The man-carrying vehicles of the type shown here would have considerably poorer performances than the robot test-rockets, as they would have to carry all the additional equipment needed to keep the pilot alive in space. The first machines of this type might be expected to reach velocities of between five and ten thousand miles an hour, and heights up to a thousand miles. They would not have enough speed to achieve permanent, stable orbits round the Earth, but would fall back again in the atmosphere when they had expended their fuel. 

4. Winged Rocket Taking Off.
Here is a man-carrying step-rocket at the moment of take-off. This is a two-stage vehicle: although with present chemical propellents at least three stages would be necessary to reach an orbit round the Earth, when fuels and motors have been developed to the limit it may prove possible to do this with a single booster. [...] The rocket takes off quite slowly at first, at an acceleration of about one gravity. In other words, it moves upwards at the same rate as an unsupported body normally falls downwards. This means that in every second, it adds about 25 m.p.h. to its speed. Not until the vehicle is much lightened through the burning of its fuel will the acceleration increase to its maximum of perhaps three gravities, and as it climbs it will slowly veer towards the east to take advantage of Earth's spin - a thousand miles an hour at the Equator.

5. Booster Separating.
This is the moment when the lower stage or booster of the two-step vessel has expended all its fuel, and drops behind as the upper stage fires its motor and continues to accelerate. [...] Since the firing will take place over desert or open sea, there will be no danger to life or property - but the equipment in the booster is much too valuable to be thrown away and every effort will be made to salvage it for another flight, by the use of breaking parachutes. 

These parachutes will be ejected while the booster is still in space - perhaps, as shown here, at the moment of separation. They will remain completely limp, even when the booster is moving at several thousand miles an hour, until the return to the upper atmosphere. The first traces of air resistance will then cause them to fill and exert their braking effect.

6. Winged Rocket Returning to Earth.
The first generation of manned rockets, because of their limited speed, will have no option but to fall back into the atmosphere after they have burnt their propellents. Their successors, however, will be able to reach the critical 18,000 m.p.h. which will give them the freedom of space. They will continue to circle the Earth effortlessly, making one revolution every ninety minutes. 

The pilot of such a vehicle, once he had completed his tests and measurements, would be faced with the problem of the return. Because his speed prevents him from "falling down," the only way he can get back to Earth is to use the rockets for braking. However, there is no need for him to destroy the whole of his 18,000 m.p.h. by rocket power alone - he can make the atmosphere do most of the work. [...] The descent would have to be carefully planned to prevent overheating, but after some two circuits of the Earth in the upper atmosphere, most of the ship's initial speed would be destroyed. During the later stages of the return, parachutes might be employed as shown here.

7. The Spacesuit.
Once in an orbit above the atmosphere, a properly protected man could quite safely step outside his spaceship, and because he would share its velocity he would simply move along beside it. He would have no sense of motion - any more than we do here on Earth as we whirl round the Sun at 66,000 m.p.h. However, he would need protection from the vacuum of space and from the solar radiation, undimmed by Earth's blanket of air.


The wearer could live, if not comfortably, at least efficiently in such a suit for periods of several hours at a time. Other designs would be evolved for work on airless planets such as the Moon, or worlds with unbreathable atmospheres.

Footnote. The spacesuit shown is based on a design by H. E. Ross and R. A. Smith, first published in 1949. As many later drawings by other artists have shown almost identical suits, this is mentioned not to claim superiority but to establish originality!

8. Practising Movement in Space.
The three crew members of a fairly large orbiting rocket-plane are seen here assembling a radio beacon on which later vessels will automatically home. They leave their vehicle, through the airlock, by kicking off in the right direction and adjusting course, as they drift along, by their jet-pistols. Safety lines are used as an additional precaution.

The crew and everything they handle are "weightless," but not, as many people think, because they are "beyond the pull of gravity." [...] We can only feel weight when we are supported by something - the floor, or a chair. A parachute jumper, a diver, or a man in a freely falling elevator can be weightless, for a few seconds, even here on Earth. A rocket beyond the atmosphere, when its motors were switched off, would be in the same condition. It and its contents would be weightless because they would have no support, but would be in "free fall," not attempting to fight gravity in any way. A spaceship in an orbit would be in a kind of fall around the Earth, not towards it, so that this condition would last indefinitely.  

To the Moon

The launching of manned satellite vehicles, which can remain above the atmosphere for as long as they please before returning to Earth, will mark the end of Phase One in the conquest of space. The time will have come to take the next step, and to break completely away from the bonds of gravity.


The first rockets to make the moonward flight will not be manned. They will be radio controlled, as may also be the tanker rockets which refuel them. In this Section we will watch the preparations that will have to be made, on Earth and in space, before the first man-carrying spaceship can land on the Moon. 

9. Triple Launching Site.
The illustration shows a launching site with a piloted, winged rocket in the foreground, and two robot tankers at the rear. The tankers would be fired first, and when a sufficient number had been assembled up in space, the manned rocket would take-off and climb up to meet them, as they circled in their orbit above the atmosphere.

10. Tankers in Orbit.
In this scene, showing a group of tankers passing over Australia, an attempt has been made to show the kind of dispersion that might be expected after a successful mass launch. An error of a few miles does not sound very much, since the rockets would have gone half-way round the Earth before reaching the orbit, but it could leave the tankers scattered over a huge volume of space. Nine are shown in the illustration: some may not be easy to find! However, as they would all have low-powered radio beacons - the aerials of which are visible on the nearer missiles - there would be no difficulty in locating them even when they were in the darkness of Earth's shadow.

11. Refuelling Rocket-Plane in Free Orbit.
Once the tankers had been successfully placed in their orbit, the next step would be to fly up one of the piloted rockets to "home" on them. When a rendezvous had been made with one of the tankers, the crew of the rocket plane would leave their ship and couple up the two vessels by means of a pipe-line. Fuel would then be pumped across from the tanker into the manned rocket.

12. Telecontrol Centre.
To this centre would come information from tracking stations all over the world, following the missiles by telescope and radar. Giant computing machines would compare the actual course of the rockets with the path they should take, and would work out the necessary corrections.

13. Refuelling Robot Rocket.
Here is the scene, in an orbit a few hundred miles above the Earth, as a robot is prepared for its trip to the Moon. [...] At the moment, the vehicle is being fuelled from one of the automatic tanker rockets. In this distance is the winged spaceship in which the technicians will return to Earth when their task is completed. A robot rocket such as this would be incapable of leaving the Earth under the power of its rather feeble motors - even if its lack of streamlining permitted it to travel at high speed through the atmosphere. It would have been assembled in space from parts carried up by freight-carrying rockets.

This scene should be compared with that in Plate 11. The principles involved are precisely the same, but the robot vehicle can be sent further into space than the manned rockets, since it is simpler and lighter - and need carry no fuel for a landing on Earth.

14. Robot Rocket Approaching Moon.
Having escaped, under the guidance of its controller, from the orbit around Earth in which it was constructed and fuelled, the little robot has now almost completed its journey to the Moon. For five days it has been coasting through space, always losing speed as Earth tries to pull it back. But now it has entered the Moon's gravitational field, and is falling more and more rapidly towards the lunar surface, now only a few hundred miles away. Unchecked, it would crash at about 5,000 m.p.h. In a few minutes, it will be time for the controller back on Earth to send the signal which will start the landing manoeuvres.

15. Designing Lunar Spaceship.
While the first robots were reconnoitring the Moon, the time would come to design man-carrying spaceships which would make the journey and return to Earth. Many of the problems to be met would already have been solved in earlier, short-range flights beyond the atmosphere, and at no stage would the designers be venturing completely into the unknown.

Here they are studying a model of the lunar spaceship. The component which will actually land on the Moon forms the upper stage stage of a three-step rocket, and will be refuelled in orbit when it has left the atmosphere. A streamlined nose-fairing, or carapace, protects the ship from overheating by air resistance during ascent. 

16. Shedding Carapace.
The ship designed to make the lunar voyage is now on the first stage of its journey. The lower boosters have spent their fuel and have dropped off: the last traces of the atmosphere are behind. During the ascent, the relatively fragile, unstreamlined nose of the spaceship was protected by a heat-resisting shell. This has now done its duty - it will not be needed again, for the vessel will never re-enter an atmosphere. It represents so much dead weight, in fact, and will be discarded at the earliest possible moment.

Here it is being blown off by small explosive charges. The sections will fall back into the atmosphere and their enormous speed will fuse into fragments too small to do any damage when they eventually reach the ground. 

17. Robot Rocket Lands on Moon.
Touchdown! The robot's automatic pilot has checked the velocity of the falling vehicle, so that it has come to rest a few feet above the lunar surface. A final burst of the steering-jets - and the first man-made object has reached another world. 

The Pioneers

Not all the first men to explore the Moon will return safely on Earth. But men faced risks and unknown hazards in the exploration of our own world, and we can be sure that, when the time comes to cross space, there will be no lack of volunteers.

Despite this, it may not be easy to find suitable crews, as the qualifications required will be extremely high. These qualifications will be mental rather than physical: astronauts need not be athletes or supermen, for space-flight will not require the physical endurance needed in polar exploration or mountaineering. It will demand very great scientific and technical skill, as well as mental stability and alertness. Every member of the crew will be an expert in at least one of the basic techniques of space-flight - astronomy, rocket engineering and electronics. It is not likely that anyone with a lesser qualification than Ph.D. would be allowed in the crew, but technical competence in itself would not be enough unless accompanied by the necessary psychological qualities.

And if two men were otherwise equally matched in all respects, the one who weighed less would be selected....

18. Manned Rocket Lands.
The spaceship is shown descending towards Mare Imbrium, or Sea of Rains, with the great isolated peak of Piton a few miles to the east.

19. The Explorers Emerge.
The first expedition will have to use its ship as a base, but it will be very inconvenient living in a cramped cabin which has really been designed to function under zero gravity - when there is no "Up" or "Down." As soon as possible, therefore, more commodious living quarters will be set up on the surface of the Moon.

This would be done by the use of pressurised, flexible domes - balloons, in fact - which would be anchored to the ground by weights and inflated with air. Such domes or "igloos" would weigh very little, and could be packed into an extremely small space for transport. Their outer walls would be silvered to reflect the intense sunlight, and airlock would permit the occupants to enter and leave. The ship's own air-conditioning plant might be used to keep the atmosphere breathable. [...] Note the sledge in the foreground. Since all stores and equipment would have only a sixth of their terrestrial weight, this would probably be the most convenient way of moving material any distance over the rough lunar surface.  

20. Erecting Solar Generators.
It is highly probable that by the time an expedition can land on the Moon, some form of safe, efficient and portable atomic generation system may be available. But if not, the Sun provides an attractive alternative. Shining continuously in the sky for fourteen earth-days on end, it pours down about two horse-power of energy on every square yard on which it falls perpendicularly. The use of solar power generators (which has already been experimentally tried out in fuel-deficient parts of the U.S.S.R.) would therefore be very practical. 

21. Supply Dropping.
The first lunar explorers will require a constant stream of supplies from Earth in order to carry out their work, and even to remain alive. If a number of bases were set up on various parts of the Moon, the difficulty of transport over the rugged lunar terrain would make a central supply base impracticable - unless this base was itself in an orbit circling the Moon.

We can assume, therefore, that stores and equipment from Earth would be shuttled across space and accumulated in an orbit perhaps a hundred miles above the Moon, where they would continue to circle effortlessly until needed. The problem then arises of landing them safely at the required spot, and one solution is shown here.

22. Retrieving Supplies.
This is the "dropping area," after the arrival of a new batch of supplies. The unit on the left has made a rather poor landing, but even so with good packing much of its contents would still be intact. And every piece would be valuable as salvage, providing metal and other materials for the Base workshop. Two more supply-bombs, which have made better landings, are seen in the distance, and the Base itself is just visible on the horizon, not far below the Earth as it hangs forever unmoving in the sky. 

23. Prospecting for Air.
The first great problem of the lunar explorers, if they are ever to establish anything in the nature of a permanent base on the Moon, is to become as self-sufficient as possible. No matter how much rocket techniques are improved, the cost of carrying supplies from Earth to Moon will always be extremely high.

The most urgent necessities of everyday life are air, water and food - in that order. We can be fairly certain that the Moon, however much its geological history may have differed from Earth's, will consist of much the same basic materials. Certainly all the elements which exist here will also be present on the Moon, free or combined. It is something of a surprise to discover that half the crust of this planet consists of the gas oxygen, combined in silicates and other compounds. It may be equally plentiful on the Moon, and given the necessary equipment its release from the lunar rocks is a purely technical problem.

However, it is not impossible that traces of water and gas, frozen solid, may exist deep in lunar crevasses where the rays of the Sun never penetrate. [...] Here we see a party of explorers investigating such a crevasse. It would be a dangerous work, but the Moon's low gravity, in which objects fall at only a sixth of their speed on Earth, would help to minimise the risks. They would be worth taking if they resulted in the discovery of water or air, frozen but merely waiting to be thawed.

One the Moon, the dividing line between light and shadow is always very sharp, owing to the absence of an atmosphere's softening influence. This does not mean, however, that all shadows would be completely black. Even if there was no Earthlight to illuminate them, in a region such as that shown here, a good deal of light would be reflected into the shadows from the brilliantly lit mountains in the distance. 

24. Lunar Ray Crater.
One lunar mystery which the first explorers will hasten to investigate is that of the brilliant rays surrounding many craters - including two of the most spectacular, Tycho and Copernicus. These streaks are the brightest objects on the Moon, but they show up well only when the Sun is high, being quite inconspicuous under low illumination. Some of these streaks are over a thousand miles in length, and pass over hill and dale with equal indifference. [...] The formation shown here is one of the very tiniest of the lunar ray craters - a small, starlike craterlet about half a mile in diameter, close to the western wall of Grimaldi. Other ray craters (such as Tycho, 54 km in diameter) are so huge that they can be seen in their entirety only from far out in space.

25. Inside Igloo.
This is the interior of one of the inflated flexible huts or igloos which the first explorers would use as a home (see Plate 19). The structure is held up entirely by the internal air-pressure of about five pounds to the square inch, and would thus be rather like a tightly inflated balloon. The roof could carry considerable loads, and is shown here supporting compressed oxygen cylinders and air-conditioning units.

26. Excavating Lunar Cavern.
If any natural caves exist on the Moon, they might be adapted to provide more spacious living quarters for the explorers. A certain amount of excavation, the sealing of cracks, and the fitting of airlocks would be all that was necessary, and the illustration shows such work in progress at the opening of a lunar cavern.

27. Commencing Permanent Dome.
The air-inflated igloos would be adequate for the first explorers, or for lightly equipped expeditions travelling over the lunar surface. But before long, larger and more permanent structures would be needed, which would have to be constructed from local materials. [...] The method of construction shown in this scene may appear very primitive, and even reminiscent of the building of the Pyramids, but it might be the most economical method where concrete was not available and steel was in short supply. Rock is being cut from the cliff in the background, and used to build up the walls of the dome. [...] The framework on the far side of the dome marks the position of the airlock through which men and vehicles can enter, and the road leading out on the lunar surface is also visible. 

28. Building-up Supplies.
In Plate 21, we saw how supplies might be dropped to provision a lunar base. The method appeared wasteful and extravagant, but might well be the only practical way in the early days of lunar exploration. At a later stage, however, regular supply ports would doubtless be set up.

Here are two "expendable freighters" that have just landed at the port. They would have been assembled in orbit round the Earth, and would have made the journey down to the Moon under automatic control (note the radar aerial jutting out on the right: this would supply the freighter's automatic pilot with data on distance and velocity of approach during the landing.)

The upper ring of tanks contains the freight and supplies; the lower one the propellent for the rocket motors which bring the vessel to the Moon. On arrival, it would be unloaded and then dismantled, since its components would be of great value to the base. The art of "cannibalisation," well-known in mechanised warfare, will reach its highest expression in the conquest of space, where every piece of metal will be valued in terms of what it has cost to transport it from Earth.

Note the ladder: with the rung-spacing shown, it would be extremely awkward to climb on Earth but is just right for the Moon. This is merely one of the many minor design changes which living under low gravity would produce.

29. Lunar Mists.
Many experienced observers are quite convinced that there are occasional local mists which obscure lunar features. Some of these mists are associated with particular craters and fissures, so perhaps there is still some very slight volcanic activity on the Moon. Such temporary obscurations have been reported in the great walled-plain Plato, in the Mare Crisium or Sea or Crises, and around the vast canyon known as the Herodotus Valley. Such mists would disperse within a few hours, and would have only the slightest effect on local visibility, as shown in this case. 

30. Air Purification Plant.
The human organism takes in oxygen and exhales carbon dioxide - CO2. The body also gives off a considerable amount of water vapour. To keep an atmosphere pure, therefore, COmust be removed and replaced with oxygen, and excess water vapour must be extracted to keep the humidity at a comfortable level. On Earth this is done by the action of plants and sunlight. In small, closed systems such as submarines, chemical means are used to replenish the air.

This illustration shows how one of the permanent lunar domes might tackle the problem. Air pumped out of the dome is compressed and circulated through pipes lying in the reflecting mirrors in the foreground. It would thus radiate its heat away, the mirrors in use being shielded so that sunlight could not fall on them. This would condense the excess water vapour, and the COcould also be removed by this means. Usually, however, the CO2-rich air would be passed on to tubes containing algae - microscopic plants which, under the action of suitably filtered sunlight, absorb carbon dioxide and release oxygen. Suitable strains of algae, fed on nitrogenous wastes from the sewerage plant, would also produce fats and proteins to feed the colonists. 

A properly designed system would be almost self-contained and could function indefinitely, the algae putting the oxygen back into the atmosphere as fast as the men took it out. The plant would in effect be a totally-enclosed scientific farm, providing food and purifying the air at the same time. 

31. Commencing Lunar Observatory.
It is difficult to over-estimate the value of the Moon as a site for astronomical observations. The virtual absence of an atmosphere means that infinitely clearer views of the heavens can be obtained than are ever possible on Earth. Our existing telescopes, if they could be transported to the Moon, could be used at ten-fold their present efficiency, and we would be able to study the stars and planets in radiations (such as the ultra-violet) which are of great importance but which are completely blocked by our own atmosphere. Visibility would always be perfect, and such mysteries as the canals of Mars could be solved with quite small telescopes. The Moon's slow rotation, which means that any given celestial body may be continuously visible for up to two weeks at a time, would also assist the astronomer in much of his work.

The Colonists

The events described in this section may still be a hundred years in the future even when the first spaceships touch-down on the Moon. [...] There can be no question that, if it proves worthwhile, the colonisation of the Moon and planets will be attempted. Most of the problems involved in such enterprises already lie within the range of present-day science, and when atomic power has been fully tamed we may expect our descendants to undertake projects of "planetary engineering" on a scale which would seem as fantastic as some of today's great irrigation schemes would have appeared to the men of the Middle Ages.

Though a good case can be made for setting up scientific bases on the Moon, it may seem unlikely that any really large settlements - any true "cities" - will ever be established there. The Moon may be bypassed as a colony, and the first major extra-terrestrial communities may be set up on Mars or Venus - where the engineering problems involved, though still severe, are less formidable. 

Only the future can answer this question, but if our satellite offers anything which Earth cannot provide, then men will spread over the face of the Moon as they have done over the surface of this world. One such possibility - that of a greater life-span than on Earth - is mentioned in connexion with Plate 39; we can be sure that there will be many others.

Some writers have speculated that the story of the United States and Europe may be repeated when we cross space. The lunar colony, if it can become self-supporting, may grow in strength, power and prestige, while the influence of Earth may wane as it exhausts its resources and its most enterprising citizens head out to the planets. The analogy is attractive, but should not be forced. It would certainly be an ironic twist of fate if, some centuries from today, our planet is the poor relation of its rich and energetic satellite.

Such ideas may seem fantastic. Of course they are: almost as fantastic, in fact, as New York City would have seemed to Christopher Columbus. 

32. Testing Nuclear Reactor.
Nuclear energy is the key to economical space-flight; it is probably true to say that until we can harness the atom to drive our spaceships, interplanetary travel will remain nothing more than a fabulously expensive scientific stunt. [...] Today's atomic reactors, or "piles," can supply unlimited amounts of energy in the form of heat and radiation, but harnessing that energy for propulsion will be an extremely difficult problem. In empty space, propulsion can be obtained only by the reaction, or rocket, principle. Mass has to be ejected in one direction to produce a recoil in the other.

Many preliminary attempts have been made to design an atomic rocket, and it seems probable that these will eventually succeed. The most promising line of development is the so-called "ion rocket." This would be a type of rocket working not by heat but by electrical energy. Powerful electric fields would accelerate charged particles in precisely the same manner as the electron-gun in the ordinary TV cathode-ray-tube squirts its beam of electrons at the screen. The recoil of these escaping particles would drive the spaceship forward.

Such an ion-rocket is shown here under test, the nuclear reactor providing the electrical power being behind the concrete shielding in the foreground. The high voltage accelerating the jet is applied along the horizontal column of insulated electrodes, and the test is being observed by television cameras.

33. Reactor Transport.
Here an unmanned, atomically-propelled, vehicle is prepared for take-off. Note the heavily shielded observation car in which the technicians approach the radioactive vessel to make the final adjustments. Observe also, the far larger chemically-fuelled spaceship in the background. The difference in size will give some idea of the improvement in performance possible with atomic propulsion. 

34. Converting Reactor.
The vessel shown in the last plate has now arrived at the lunar colony and its atomic pile is being installed in the power-station. During the flight from Earth, the pile will have expended only a very small fraction of the energy locked in its mass, and it will be able to run the generators of the colony for many years. Since the reactor will be violently radioactive, all the work of reassembly will have to be done by remotely-operated mechanisms. 

35. Erecting Overhead Transporting Lines.
Transport over long distances on the Moon presents some interesting problems. The use of rockets would probably be too expensive, and in the absence of any appreciable atmosphere aircraft are out of the question. This means that the colonists will have to rely on surface methods of transport.

Pressurised vehicles, using caterpillar tracks or balloon tyres, will doubtless be evolved for general cross-country work. For high-speed services, when there are enough centres of population to make it worthwhile, rail systems will come into their own. The lack of air resistance would enable speeds of several hundred miles an hour to be employed with little power, so that in a few hours it would be possible to go from one pole of the Moon to the other. A monorail system would have many advantages, and the low gravity would facilitate the construction of bridges and allow the use of very steep grades.

The alternative shown here, however, would seem to be very suitable for lunar conditions - especially where the terrain was very rugged and it might be difficult to lay tracks. Overhead transport lines have long done valuable work in parts of this planet where roads are non-existent, though their use has been restricted to freight, ores and other loads where speed was not essential.

The great spans that could be obtained on the Moon would reduce the number of supporting towers per mile to a relatively low figure, even if heavy, high-speed loads were sent along the lines. The erection of such a transporter-line is shown here, two of the cabs being used as mobile workshops which can move forward as the line is extended.  

36. The Lunar Base.
After the construction of the first temporary camps by the early explorers, we may expect the building of large bases which would eventually, if all went well, evolve into true cities. Such a lunar base would consist of several pressure-domes, linked together with airlocks which would close automatically in the event of failure in any one dome. Some domes would be residential, others devoted to various scientific and technical duties - power, transport, communications, research, air, food production, and so on. The little community would be surrounded by the transparent tubes of the hydroponic farms (see Plate 37), and would have its own fleet of transport vehicles. 
This scene depicts the road and cable entrances to such a base. [...] The shape of the car is not, of course, dictated by any considerations of streamlining. Since it has to be pressurised, it would probably have hemispherical ends as shown. Note the observation window running round the dome. There might be a kind of promenade here so that the occupants of the base could look at the stars and scenery whenever they wished. Making the whole dome transparent would be technically very difficult, and would probably be unwise for reasons of safety and temperature control. The structure on the supporting tower in the back ground is a small observatory, housing telescopes and other instruments.

37. Hydroponic Farm.
The problem of growing food on the Moon has already been mentioned in connexion with air purification (Plate 30), and in view of the balance between plant and animal life the two subjects are closely linked together. For large-scale food production under the conditions prevailing on the Moon, hydroponic or "soilless" farming would seem to be the ideal solution. It has already been employed with great success in areas where fertile ground is limited - for example in Japan and on some of the Pacific islands.

Instead of growing crops in soil, the plants are supported on wire-netting and their roots dip into solutions containing the necessary salts. In this way, all the factors determining growth are under direct control, and very large crops can be produced. On Earth, the system is expensive in terms of capital and labour, but on the Moon it would be the most economical - and perhaps the only - method of food-production. 

38. Inside Hydroponic Tube.
Here is a section of a hydroponic farm, showing the crops being tended by men wearing breathing masks to protect them from the humid, CO2-enriched atmosphere.

39. Lunar Gymnasium.
Some spectacular athletic feats would be possible on the Moon, though whether they would be allowed to count for record purposes is open to question! One could even fly, with suitable wings, in an enclosed space where the air-pressure was kept at the same value as on Earth, and it would not be too difficult to jump thirty feet high.

None of the - at first sight - prodigious feats shown in this illustration is at all remarkable when analysed. Thus the man at the base of the inverted human pyramid is really supporting little more than his own weight. In the background, a spinning table is acting as a simple centrifuge, so that those on it will feel forces equivalent to Earth's gravity.

It must not be forgotten that although weight would be reduced to a sixth on the Moon, inertia or mass would be completely unaltered. In other words, though it would be much easier to support any given body without moving it, the effort to set it in motion - or to stop it when it had started - would be just the same as on Earth.

40. Inside Lunar City.
As the lunar colony expands, the bases will be replaced by true cities, housing thousands of men, women and children. To them their mode of life will seem perfectly natural, and indeed a lunar city could be scarcely more artificial than present-day London or New York. [...] Lunar architecture would doubtless evolve along lines which no-one can predict today. The lower gravity would allow much more daring experiments than are possible on Earth, and vertical distances would be treated with some contempt. 

41. Lunar Space-Port.
The Control Centre in the middle distance would be the heart of the space-port, with all its communications equipment. Vision would play a negligible part in flight operations, and everything would be done by radio and radar. Observation windows would be quite unnecessary, but would doubtless be provided so that the impressive spectacles of landing or departure could be watched.

On the right are the mirrors of solar power generators (see Plate 20) with six large fuel-tanks just beyond them. The tanks are partly buried; when rocket propellents are stored in vacuum there is little danger of explosion, but it is important to protect the tanks from the intense heat of the long lunar day.

Running away into the distance is the track of an electromagnetic launcher. It would be possible to shoot containers of fuel clear off the Moon, up to spaceships circling in orbit, by means of such a track. Powerful magnets, energised in sequence one after the other, would give properly constructed fuel-capsules the necessary velocity of some 4,000 miles an hour, by accelerating them at 50 gravities for distances up to two miles. [...] In this manner, fuel could be conveyed to spaceships without the expenditure of any rocket propellents at all.

Instead of having an assigned run-way to land on, an incoming ship would be allocated one of the marked squares visible in the distance. The long buildings are pressurised hangers and workshops; though many servicing operations would have to be carried out in the open, there are others which could be done efficiently only by mechanics working in an atmosphere.

The array of horizontal troughs in the centre foreground is part of the air-conditioning plant, shown in more detail in Plate 30.

42. Eclipse Seen from Moon.
Once every month, at each New Moon, the Sun, Moon and Earth - in that order - lie in approximately the same line. But only approximately, because the Moon's orbit is tilted slightly so that on most occasions the Moon passes above or below the Sun.

About once every two years, on the average, the line-up is exact and the Moon completely covers the Sun. From Earth's point of view, this is a total eclipse of the Sun - one of the most beautiful and awe-inspiring phenomena in the whole of nature. Here we see such an eclipse, as it would appear to an observer on the Moon, watching through a small telescope. [...] From space, Earth must be one of the most beautiful of all the planets, thanks to its seas and clouds. The atmosphere would partly veil the surface features, and would conceal them completely near the edge of the disc. And often - as is shown here - the reflection of the Sun could be seen as a blinding star on the face of the ocean.

43. Space Station.
The planets and their many satellites will not be the only abodes of men when the Space Age gets under way. Artificial satellites - space-stations - will be built to carry out various duties, some of which we can already foresee but others which only the future will reveal.


Some of these stations will be used to observe the weather, and when we can survey the entire Earth at one glance our knowledge of meteorology should be vastly increased. Others will be floating space-ports, fuelling and servicing spaceships on their way to and from Earth. Still others will be used as TV and radio stations, providing a more complete coverage on all frequencies than will ever be possible from transmitters on Earth's surface. The economic consequences of this will be enormous, and the orbital radio stations may by themselves pay for the initial development of astronautics. 

44. Orbiting Martian Probe.
The robot rockets which will give man his first close-ups of the Moon will also be used to survey the other planets. Surprisingly enough, it does not require much extra fuel to make the enormously longer journey to Mars - the most interesting of all our neighbours in space. At its closest, Mars comes to within 35,000,000 miles of Earth. However, the short, direct journey between the orbits of the two planets is hopelessly extravagant in fuel. The first robots will travel on the most economical path to Mars - a sweeping curve, almost 300,000,000 miles long, leading them to the other side of the Sun.

It would take about eight months for the robot "probe" to make the trip, coasting freely under the impulse which its rockets gave it when it left the vicinity of Earth. Though it would be launched as accurately as possible, its electronic brain would have to make the final corrections which would cause it to orbit Mars, becoming a third and still smaller companion to the planet's tiny moons, Phobos and Deimos.

45. The Price.......