EPILOGUE.
'Their little universe is very young, and its god is still a child. But it is too soon to judge them; when We return in the Last Days, We will consider what should be saved.'
SOURCES AND ACKNOWLEDGEMENTS.
SOURCES.
Chapter 1: The Kuiper Belt.
For a description of Captain Chandler's hunting ground, discovered as recently as 1992, see 'The Kuiper Belt' by Jane X. Luu and David C. Jewitt (Scientific American, May 1996)
Chapter 3: Rehabilitation.
I believed that I had invented the palm-to-palm transfer of information, so it was mortifying to discover that Nicholas ("Being Digital") Negroponte (Hodder and Stoughton, 1995) and his MIT Media Lab have been working on the idea for years...
Chapter 4: Star City.
The concept of a 'ring around the world' in the geostationary orbit (CEO), linked to the Earth by towers at the Equator, may seem utterly fantastic but in fact has a firm scientific basis. It is an obvious extension of the 'space elevator' invented by the St Petersburg engineer Yuri Artsutanov, whom I had the pleasure of meeting in 1982, when his city had a different name.
Yuri pointed out that it was theoretically possible to lay a cable between the Earth and a satellite hovering over the same spot on the Equator which it does when placed in the CEO, home of most of today's communications satellites. From this beginning, a space elevator (or in Yuri's picturesque phrase, 'cosmic funicular') could be established, and payloads could be carried up to the CEO purely by electrical energy. Rocket propulsion would be needed only for the remainder of the journey.
In addition to avoiding the danger, noise and environmental hazards of rocketry, the space elevator would make possible quite astonishing reductions in the cost of all space missions. Electricity is cheap, and it would require only about a hundred dollars' worth to take one person to orbit. And the round trip would cost about ten dollars, as most of the energy would be recovered on the downward journey! (Of course, catering and inflight movies would put up the price of the ticket. Would you believe a thousand dollars to CEO and back?) The theory is impeccable: but does any material exist with sufficient tensile strength to hang all the way down to the Equator from an altitude of 36,000 kilometres, with enough margin left over to raise useful payloads? When Yuri wrote his paper, only one substance met these rather stringent specifications -crystalline carbon, better known as diamond. Unfortunately, the necessary megaton quantities are not readily available on the open market, though in "2061: Odyssey Three" I gave reasons for thinking that they might exist at the core of Jupiter. In "The Fountains of Paradise" I suggested a more accessible source - orbiting factories where diamonds might be grown under zero-gravity conditions.
The first 'small step' towards the space elevator was attempted in August 1992 on the Shuttle Atlantis, when one experiment involved the release - and retrieval - of a payload on a 21-kilometre-long tether. Unfortunately the playing-out mechanism jammed after only a few hundred metres.
I was very flattered when the Atlantis crew produced The Fountains of Paradise during their orbital press conference, and Mission Specialist Jeffrey Hoffman sent me the autographed copy on their return to Earth.
The second tether experiment, in February 1996, was slightly more successful: the payload was indeed deployed to its full distance, but during retrieval the cable was severed, owing to an electrical discharge caused by faulty insulation. This may have been a lucky accident - perhaps the equivalent of a blown fuse: I cannot help recalling that some of Ben Franklin's contemporaries were killed when they attempted to repeat his famous - and risky - experiment of flying a kite during a thunderstorm.
Apart from possible dangers, playing-out tethered payloads from the Shuttle appears rather like fly-fishing: is not as easy as it looks. But eventually the final 'giant leap' will be made - all the way down to the Equator.
Meanwhile, the discovery of the third form of carbon, buckminsterfullerene (C60) has made the concept of the space elevator much more plausible. In 1990 a group of chemists at Rice University, Houston, produced a tubular form of C60 - which has far greater tensile strength than diamond. The group's leader, Dr. Smalley, even went so far as to claim it was the strongest material that could ever exist - and added that it would make possible the construction of the space elevator.
(Stop Press News: I am delighted to know that Dr. Smalley has shared the 1996 Nobel Prize in Chemistry for this work.) And now for a truly amazing coincidence - one so eerie that it makes me wonder Who Is In Charge.
Buckminster Fuller died in 1983, so never lived to see the discovery of the 'buckyballs' and 'buckytubes' which have given him much greater posthumous fame. During one of the last of his many world trips, I had the pleasure of flying him and his wife Anne around Sri Lanka, and showed them some of the locations featured in The Fountains of Paradise. Shortly afterwards, I made a recording from the novel on a 12" (remember them?) LP record (Caedmon TC 1606) and Bucky was kind enough to write the sleeve notes. They ended with a surprising revelation, which may well have triggered my own thinking about 'Star City': 'In 1951 I designed a free-floating tensegrity ring-bridge to be installed way out from and around the Earth's equator. Within this "halo" bridge, the Earth would continue its spinning while the circular bridge would revolve at its own rate. I foresaw Earthian traffic vertically ascending to the bridge, revolving and descending at preferred Earth loci'
I have no doubt that, if the human race decides to make such an investment (a trivial one, according to some estimates of economic growth), 'Star City' could be constructed. In addition to providing new styles of living, and giving visitors from low-gravity worlds like Mars and the Moon better access to the Home Planet, it would eliminate all rocketry from the Earth's surface and relegate it to deep space, where it belongs (Though I hope there would be occasional anniversary re-enactments at Cape Kennedy, to bring back the excitement of the pioneering days.) Almost certainly most of the City would be empty scaffolding, and only a very small fraction would be occupied or used for scientific or technological purposes. After all, each of the Towers would be the equivalent of a ten-million-floor skyscraper - and the circumference of the ring around the geostationary orbit would be more than half the distance to the Moon! Many times the entire population of the human race could be housed in such a volume of space, if it was all enclosed. (This would pose some interesting logistics problems, which I am content to leave as 'an exercise for the student'.)
Chapter 5: Education.
I was astonished to read in a newspaper on 19 July 1996 that Dr. Chris Winter, head of British Telecom's Artificial Life Team, believes that the information and storage device I described in this chapter could be developed within 30 years! (In my 1956 novel The City and the Stars I put it more than a billion years in the future... obviously a serious failure of imagination.) Dr. Winter states that it would allow us to 'recreate a person physically, emotionally and spiritually', and estimates that the memory requirements would be about 10 terabytes (10e13 bytes), two orders of magnitude less than the petabyte (10e15 bytes) I suggest.
And I wish I'd thought of Dr. Winter's name for this device, which will certainly start some fierce debates in ecclesiastical circles: the 'Soul Catcher'... For its application to interstellar travel, see following note on Chapter 9.
For an excellent history of the 'Beanstalk' concept (as well as many other even farther-out ideas such as anti-gravity and space-warps) see Robert L. Forward's "Indistinguishable From Magic" (Baen 1995).
Chapter 7: Infinite Energy.
If the inconceivable energy of the Zero Point Field (sometimes referred to as 'quantum fluctuations' or 'vacuum energy') can ever be tapped, the impact upon our civilization will be incalculable. All present sources of power - oil, coal, nuclear, hydro, solar - would become obsolete, and so would many of our fears about environmental pollution. They would all be wrapped up in one big worry - heat pollution. All energy eventually degrades to heat, and if everyone had a few million kilowatts to play with, this planet would soon be heading the way of Venus - several hundred degrees in the shade.
However, there is a bright side to the picture: there may be no other way of averting the next Ice Age, which otherwise is inevitable ('Civilization is an interval between Ice Ages' - Will Durant: "The Story of Civilization", Fine Communications, US, 1993) Even as I write this, many competent engineers, in laboratories all over the world, claim to be tapping this new energy source. Some idea of its magnitude is contained in a famous remark by the physicist Richard Feynman, to the effect that the energy in a coffee-mug's volume (any such volume, anywhere!) is enough to boil all the oceans of the world. This, surely, is a thought to give one pause. By comparison, nuclear energy looks as feeble as a damp match.
And how many supernovae, I wonder, really are industrial accidents?
Chapter 9: Skyland.
One of the main problems of getting around in Star City would be caused by the sheer distances involved: if you wanted to visit a friend in the next Tower (and communications will never completely replace contact, despite all advances in Virtual Reality) it could be the equivalent of a trip to the Moon. Even with the fastest elevators this would involve days rather than hours, or else accelerations quite unacceptable to people who had adapted to low-gravity life.
The concept of an 'inertialess drive' - i.e. a propulsion system that acts on every atom of a body so that no strains are produced when it accelerates - was probably invented by the master of the 'Space Opera', E.E. Smith, in the 1930s. It is not as improbable as it sounds - because a gravitational field acts in precisely this manner.
If you fall freely near the Earth (neglecting the effects of air resistance) you will increase speed by just under ten metres per second, every second. Yet you will feel weightless - there will be no sense of acceleration, even though your velocity is increasing by one kilometre a second, every minute and a half!
And this would still be true if you were falling in Jupiter's gravity (just over two-and-a-half times Earth's) or even the enormously more powerful field of a white dwarf or neutron star (millions or billions of times greater). You would feel nothing, even if you had approached the velocity of light from a standing start in a matter of minutes. However, if you were foolish enough to get within a few radii of the attracting object, its field would no longer be uniform over the whole length of your body, and tidal forces would soon tear you to pieces. For further details, see my deplorable but accurately-titled short story 'Neutron Tide' (in "The Wind from the Sun").
An 'inertialess drive', which would act exactly like a controllable gravity field, had never been discussed seriously outside the pages of science fiction until very recently. But in 1994 three American physicists did exactly this, developing some ideas of the great Russian physicist Andrei Sakharov.
'Inertia as a Zero-Point Field Lorentz Force' by B. Haisch, A. Rueda & H. F. Puthoff (Physics Review A, February 1994) may one day be regarded as a landmark paper, and for the purposes of fiction I have made it so. It addresses a problem so fundamental that it is normally taken for granted, with a that's-just-the-way-the-universe-is-made shrug of the shoulders.
The question HR&P asked is: 'What gives an object mass (or inertia) so that it requires an effort to start it moving, and exactly the same effort to restore it to its original state?'
Their provisional answer depends on the astonishing - and outside the physicists' ivory towers -little-known fact that so-called 'empty' space is actually a cauldron of seething energies - the Zero-Point Field (see note above). HR&P suggest that both inertia and gravitation are electromagnetic phenomena, resulting from interaction with this field.
There have been countless attempts, going all the way back to Faraday, to link gravity and magnetism, and although many experimenters have claimed success, none of their results has ever been verified. However, if HR&P's theory can be proved, it opens up the prospect - however remote - of anti-gravity, 'space drives' and the even more fantastic possibility of controlling inertia. This could lead to some interesting situations: if you gave someone the gentlest touch, they would promptly disappear at thousands of kilometres an hour, until they bounced off the other side of the room a fraction of a millisecond later. The good news is that traffic accidents would be virtually impossible; automobiles - and passengers -could collide harmlessly at any speed.
(And you think that today's life-styles are already too hectic?) The 'weightlessness' which we now take for granted in space missions - and which millions of tourists will be enjoying in the next century - would have seemed like magic to our grandparents. But the abolition - or merely the reduction - of inertia is quite another matter, and may be completely impossible.* But it's a nice thought, for it could provide the equivalent of 'teleportation': you could travel anywhere (at least on Earth) almost instantaneously. Frankly, I don't know how 'Star City' could manage without it...
* As every Trekker knows, the Starship Enterprise uses 'inertial dampers' to solve this particular problem. When asked how these work, the series' technical advisor gave the only possible answer: 'very well, thank you.' (See "The Physics of Star Trek" by Lawrence Krauss: HarperCollins, 1996.) One of the assumptions I have made in this novel is that Einstein is correct, and that no signal - or object - can exceed the speed of light. A number of highly mathematical papers have recently appeared suggesting that, as countless science-fiction writers have taken for granted, galactic hitch-hikers may not have to suffer this annoying disability.
On the whole, I hope they are right - but there seems one fundamental objection. If FTL is possible, where are all those hitchhikers - or at least the well-heeled tourists?
One answer is that no sensible ETs will ever build interstellar vehicles, for precisely the same reason that we have never developed coal-fuelled airships: there are much better ways of doing the job.
The surprisingly small number of 'bits' required to define a human being, or to store all the information one could possibly acquire in a lifetime, is discussed in 'Machine Intelligence, the Cost of Interstellar Travel and Fermi's Paradox' by Louis K. Scheffer (Quarterly Journal of the Royal Astronomical Society, Vol. 35, No. 2, June 1994: pp. 157-75). This paper (surely the most mind-stretching that the staid QJRAS has published in its entire career!) estimates that the total mental state of a 100-year-old human with a perfect memory could be represented by 10 to the 15th bits (one petabit). Even today's optical fibres could transmit this amount of information in a matter of minutes.
My suggestion that a Star Trek transporter would still be unavailable in 3001 may therefore appear ludicrously shortsighted a mere century from now* and the present lack of interstellar tourists is simply due to the fact that no receiving equipment has yet been set up on Earth. Perhaps it's already on its way by slow-boat...
* However, for a diametrically opposing view, see the above-mentioned "Physics of Star Trek".
Chapter 15: Falcon.
It gives me particular pleasure to pay this tribute to the crew of Apollo 15. On their return from the Moon they sent me the beautiful relief map of Falcon's landing site, which now has pride of place in my office. It shows the routes taken by the Lunar Rover during its three excursions, one of which skirted Earthlight Crater. The map bears the inscription: 'To Arthur Clarke from the crew of Apollo 15 with many thanks for your visions of space. Dave Scott, Al Worden, Jim Irwin.' In return, I have now dedicated "Earthlight" (which, written in 1953, was set in the territory the Rover was to drive over in 1971): 'To Dave Scott and Jim Irwin, the first men to enter this land, and to Al Worden, who watched over them from orbit.'
After covering the Apollo 15 landing in the CBS studio with Walter Cronkite and Wally Schirra, I flew to Mission Control to watch the re-entry and splashdown. I was sitting beside Al Worden's little daughter when she was the first to notice that one of the capsule's three parachutes had failed to deploy. It was a tense moment, but luckily the remaining two were quite adequate for the job.
Chapter 16: Asteroid 7794.
See Chapter 18 of "2001: A Space Odyssey" for the description of the probe's impact. Precisely such an experiment is now being planned for the forthcoming Clementine 2 mission.
I am a little embarrassed to see that in my first Space Odyssey the discovery of Asteroid 7794 was attributed to the Lunar Observatory - in 1997! Well, I'll move it to 2017 - in time for my 100th birthday.
Just a few hours after writing the above, I was delighted to learn that Asteroid 4923 (1981 EO27), discovered by S. J. Bus at Siding Spring, Australia, on 2 March 1981, has been named Clarke, partly in recognition of Project Spaceguard (see "Rendezvous with Rama" and "The Hammer of God"). I was informed, with profound apologies, that owing to an unfortunate oversight Number 2001 was no longer available, having been allocated to somebody named A. Einstein. Excuses, excuses.
But I was very pleased to learn that Asteroid 5020, discovered on the same day as 4923, has been named Asimov - though saddened by the fact that my old friend could never know.
Chapter 17: Ganymede.
As explained in the Valediction, and in the Author's Notes to "2010 Odyssey Two" and "2061 Odyssey Three", I had hoped that the ambitious Galileo Mission to Jupiter and its moons would by now have given us much more detailed knowledge - as well as stunning close-ups - of these strange worlds.
Well, after many delays, Galileo reached its first objective - Jupiter itself - and is performing admirably. But, alas, there is a problem - for some reason, the main antenna never unfolded. This means that images have to be sent back via a low-gain antenna, at an agonizingly slow rate. Although miracles of onboard computer reprogramming have been done to compensate for this, it will still require hours to receive information that should have been sent in minutes.
So we must be patient - and I was in the tantalizing position of exploring Ganymede in fiction just before Galileo started to do so in reality, on 27 June 1996.
On 11 July 1996, just two days before finishing this book, I downloaded the first images from JPL; luckily nothing - so far! -contradicts my descriptions. But if the current vistas of cratered ice-fields suddenly give way to palm trees and tropical beaches - or, worse still, YANKEE GO HOME signs, I'll be in real trouble .
I am particularly looking forward to close-ups of 'Ganymede City' (Chapter 17). This striking formation is exactly as I described it - though I hesitated to do so for fear that my 'discovery' might be front-paged by the National Prevaricator. To my eyes it appears considerably more artificial than the notorious 'Mars Face' and its surroundings. And if its streets and avenues are ten kilometres wide - so what? Perhaps the Medes were BIG...
The city will be found on the NASA Voyager images 20637.02 and 20637.29, or more conveniently in Figure 23.8 of John H. Rogers's monumental "The Giant Planet Jupiter" (Cambridge University Press, 1995).
Chapter 19: The Madness of Mankind.
For visual evidence supporting Khan's startling assertion that most of mankind has been at least partially insane, see Episode 22, 'Meeting Mary', in my television series Arthur C. Clarke's Mysterious Universe. And bear in mind that Christians represent only a very small subset of our species: far greater numbers of devotees than have ever worshipped the Virgin Mary have given equal reverence to such totally incompatible divinities as Rama, Kali, Siva, Thor, Wotan, Jupiter, Osiris, etc. etc....
The most striking - and pitiful - example of a brilliant man whose beliefs turned him into a raving lunatic is that of Conan Doyle. Despite endless exposures of his favourite psychics as frauds, his faith in them remained unshaken. And the creator of Sherlock Holmes even tried to convince the great magician Harry Houdini that he 'dematerialized' himself to perform his feats of escapology - often based on tricks which, as Dr. Watson was fond of saying, were 'absurdly simple'. (See the essay 'The Irrelevance of Conan Doyle' in Martin Gardner's "The Night is Large", St Martin's Press, US, 1996.) For details of the Inquisition, whose pious atrocities make Pol Pot look positively benign, see Carl Sagan's devastating attack on New Age Nitwittery, "The Demon-Haunted World: Science as a Candle in the Dark" (Headline, 1995). I wish it - and Martin's book - could be made required reading in every high school and college.
At least the US Department of Immigration has taken action against one religion-inspired barbarity. Time Magazine ('Milestones', 24 June 1996) reports that asylum must now be granted to girls threatened with genital mutilation in their countries of origin.
I had already written this chapter when I came across Anthony Storr's "Feet of Clay: A Study of Gurus" (HarperCollins, 1996), which is a virtual textbook on this depressing subject. It is hard to believe that one holy fraud, by the time the US Marshals belatedly arrested him, had accumulated ninety-three Rolls-Royces! Even worse - eighty-three per cent of his thousands of American dupes had been to college, and thus qualify for my favourite definition of an intellectual: 'Someone who has been educated beyond his/her intelligence.'