Of a Fire on the Moon (9780553390629) (48 page)

CHILDREN

Perfect plastic poem, for it left the same aesthetic satisfaction in the heart as the smell of vinyl.

The subtle imbalance in the computer was that it had all the power to push man out of a reasonable relation to his environment and into an accelerated relation. It had created plastic brainpower ready to flow in the direction of every problem even as plastic sometimes gives signs of pushing toward every manifestation of flesh and form. The digital computer was crude in comparison to the brain. The mind had ten billion neurons each equal to a switch in a computer. The mind could store two hundred billion billion bits of information, the largest computers could hold but a ten-thousandth of that. The mind worked on a tenth of a volt of electricity—its economy of power was ten million times less wasteful than the computer.

But the computer worked in nanoseconds and picoseconds, billionths and trillionths of a second, the computer was one hundred thousand times faster switch for switch than the brain. So the computer could perform calculations in a minute which would occupy the brain for ten weeks, or indeed for almost a year if one assumed the brain was to work no more than forty hours a week. A minute to a year. There was the strength of the computer, even greater than the horsepower of Saturn V compared to a single man, yes, the digital computer was one hundred thousand times more powerful than the mind, even if it achieved that power at ten million times the expenditure of electrical energy. Such costs meant nothing yet for they were still insignificant in relation to all the demands for electrical power, but then so were the rates of pollution low when industry began.

Yet the problem was probably not here, for the computers would become more efficient. As they grew smaller so, relatively, would their speed increase and their ability to store information. The problem was that the new brainpower was plastic, it would push to fill vacuums, press on to simulate what had hitherto been out of the range of simulation, occupy problems whose outer margins would be lost as the center was sucked into the binary system. All this excess brainpower! It could end by having as little to do with the real needs or natural balance of the earth as the delivery of ten automobiles to every citizen of the earth. Once delivered, people might of course use them, if only to crash them, but it would make for a most peculiar world—everybody living with ten cars—the structures of homes and streets would turn inside out, and the enterprising would look into the possibilities of twenty cars. If there had been a period in the history of culture when all human effort gave promise of being translated ultimately into money, now the time was conceivably approaching when the money of moneys would be here, the quintessence of number, the world reclassified by combinations of 1 and 0, nothing more. So had Leibnitz once attempted—in his lust to create a symbolic logic—to show that God was 1 and had created the world out of 0. Now
another accounting was near. For if one could eventually define all existence by variations of 1 and 0, how easy would become the next step—to dissolve the world. Down all the steps of entropy we would flow.

If one were, however, to condemn the computer for this nightmare of a future, condemn it today for its automation, its new methods in banking, condemn its use by the Bar Association and the Stock Exchange and Boeing and the Bureau of Mines, the Cancer Society for research, condemn Control Data Corporation and General Dynamics, General Motors and General Electric, condemn computer analysis of the Dead Sea Scrolls, condemn its employment in the Department of Commerce and the Department of Defense, condemn Douglas Aircraft and Dow Chemical, du Pont and the election forecasts, condemn the FAA and freight trains shunted by program in and out of freight yards, condemn General Precision and Goodrich, Goodyear and Charles Goren, Hoffman Electronics and Hughes Aircraft, IBM 704 and IBM 1401, condemn the Industrial Advertising Research Institute and the Internal Revenue, International Air Transport and Johnson’s Wax, Kresge Eye Institute and Lincoln Laboratory, the Public Library and Lockheed Aircraft, McGraw Hill and Merrill Lynch Pierce Fenner and Smith, Minneapolis Honeywell, Monsanto, NATO and the National Cash Register—the names go by like sounds in a coffee-house poem—the U.S. Navy and the National Bureau of Standards, Ohio State, Patent Office, Philco, Phillips Petroleum, Radcliffe, the Rand Corporation, Rockefeller Institute and the Sara Lee Bakeries, the Signal Corps and Social Security, Southern Methodist and Sun Oil, TWA and UNESCO, Union Carbide, USC, the Upjohn Company, Wall Street, Westinghouse—does one condemn them for using ADAM and BINAC and BRAINIAC, CALCULO and CLASS, ENIAC, ERMA, ILLIAC, JOHNNIAC, LARC and MANIAC? Does one forbid MIPS, MOBIDIC and MUSE, RAMAC, RAYDAC, RECOMP and SAGE, or not permit STRETCH, UNIVAC or VIDIAC, wait there is still DIDAC and EURATOM, FIELDATA,
FINER and HIPO, HAYSTAQ and IRE, MEDLARS, BIAX and MIND, NADGE, NANWEP and NORAD, PLATO, TASCON and ARTOC. There is AUTOPROMPT, AUTOTAG, APT, AID and AIEE but maybe the point has been made. It will come as no surprise that without that detumescence of development in computers which saturated the electronics of the Fifties and the Sixties, without the five IBM 360/75 computers and the IBM 1460’s on the floor of the Real-Time Computer Complex at Mission Control Center there would have been no trip to the moon, and indeed no Instrument Unit on Apollo-Saturn. Rockets would still be punching holes in clouds, for without a digital computer no trajectories could be calculated. The simple work of addition, subtraction, multiplication and division to calculate a trip to Venus would take one man eight hundred years. Yet now there were supercomputers to calculate the journey in thirty seconds. That plastic brainpower could turn over every straw in the haystack to find the needle. The rush to extermination or apocalypse was being accelerated by every computer on earth.

Of course, the computer on the Lem was nowhere so vast. The brain capacity of computers designed in the same period was roughly proportional to their volume, and this computer, identical to the one on the Command Module, was two feet long, one foot high, and six inches wide. It weighed seventy pounds and consumed seventy watts and had a vocabulary of 38,916 sixteen-bit words, a way of stating that the Guidance Computer could take information in the form of ones and zeros in any variety up to sixteen units in a row. That made one word among 38,916 words. Hordes of navigation data and engine data had thus been laid in for reference; also, a series of programs which had been designed to keep the Lem on its trajectory by issuing precise engine and thruster commands. Another of its functions was to keep the Inertial Measurement Unit or gyroscope in constant alignment with the stars. It was capable to a small degree of correcting malfunctions
in its own system, and it could also compute navigation information and display it to the astronauts, or answer their questions, through a combination of Display and Keyboard called a DSKY which had lighted numbers in a small frosted window to show answers, offer information, or blink out alarms. In turn, the astronauts communicated with the computer through keys in the DSKY which they punched like adding machine tabs to begin computer actions. The keys went from the number 0 to 9, there was a key for plus and minus, and other keys marked
VERB, NOUN, CLEAR, PRO, KEY REL, ENTER
and
RSET
.

The Guidance Computer was the major part of the Primary Guidance and Navigation Section (whose acronym was PGNS) and so was sometimes called Pings to distinguish it from AGS, the Abort Guidance Section, a smaller computer and inertial system ready to take over if Pings failed. Ags could hardly fly the mission, it was there for backup in case the Guidance Computer failed and abort was necessary to return the Lem to the Command Module. So the success of the landing on the moon would depend on Pings’ speed in processing the variety of information it would be absorbing, and its ability to issue commands as the Lem proceeded down. Coming into the maw of its calculations would be questions the astronauts put in on the DSKY, and programs they ordered it to initiate; coming in from other sources and sensors would be all the evidence of altitude change, velocity change, and fuel consumption. Since the rendezvous radar would be sending and receiving signals from the separated Command Module, so too would rendezvous radar be offering data to Pings on the change of distance and the relative position of the two ships. In addition, the landing radar would also be entering its evidence in the Guidance Computer, and to increase confusion the landing radar was bound to disagree with Pings, for it would be bouncing signals off the literal moon ground, rather than estimating like Pings where the ground ought to be on the basis of past observations and calculations. Therefore the computer would be having to make last-minute adjustments at a great rate. But here is Aldrin on the matter:

The Pings obviously would have enough to do. If it had almost thirty-nine thousand words, most of them were already fixed. Only two thousand could be applied to a transient problem. In the welter of functions which might descend upon it, beleaguered as a short-order cook when he has lost a series of orders at the rush hour, the Pings had the power to give priority to particular functions, set other functions aside, or even cease calculations for a moment if an error were made, or a discrepancy could not be accounted for, or information was simply coming in faster than it could be processed. The Pings was presumably an effective computer for its size, but weight was crucial, and so it was squeezed in its tasks. It bore the same relation to the computers at Mission Control that a dollar bill bears to a thousand dollar bill. As limited, relatively, were the services it could purchase. Of course the descent from beginning to end could have been computed on the ground from the tracking of the huge antennae in the Manned Space Flight Network, and in fact it was, but to be dependent on Mission Control for the landing was too dangerous: the telemetered data could always fail. Static, or any other blocking of the signal, could cut out crucial instants of data. Often did. Besides, the ground was a quarter of a million miles away, and information therefore took more than a second to arrive; if it took even an instant
to process and send back, three seconds could elapse in the interval, a catastrophe in a situation where the controls on the Lem were rapidly going wrong. So the limited seventy-pound Guidance Computer with its 38,916 words was going to be the chief pilot for the first part of the trip down, its indispensable function to calculate the ratio between the fuel which still remained and the miles yet to descend. Without a functioning computer those rates were next to impossible for a pilot to estimate, since the Lem would be traveling at several thousand miles an hour when it began its descent and settling at only several feet a second by the end. And it must be remembered that one could not fly the Lem down, which is to say one did not have the fuel to take it through circles, allow it to descend, then rise again, then take a long turn. There would be some maneuvering available at the end, but for the majority of the descent, few were the adjustments to be made with the trajectory. The Lem was still riding on the effects of the momentum which had first brought it to the moon, riding like a ball thrown into a canyon. One might nudge it a degree or two from side to side, one might brake its fall a little more or less, but essentially its momentum was its capital and it was traveling on a braking ballistic curve toward the moon ground—it was not going to wheel and circle and soar and turn and negotiate a descent—not in a lunar vacuum. So little changes of attitude or braking thrust were large in importance, and a computer could estimate their effect on fuel far more rapidly than a man. Yet, given its limited capacity and variety of tasks, it was obvious that one burden of preparation at NASA was to make certain Pings never got into the condition of a quarterback to whom everybody is talking in the huddle when the time-outs are used up and the clock is running into the end of the game.

Who could be more aware of such difficulties than the flight controllers in the Mission Control Room? The functions of a computer were always in as much danger of going awry as society is in danger of some final collapse into crime; experts and chains of experts were forever at work on electronic species of crime
detection—they were vigilant to search for sneak circuits in the computer, circuits which if exercised at the same time would interreact in ways no one had foreseen. There were millions of switches and billions of permutations: complex electrical circuits were like patients with modern viruses—after prescribing several medicines, the doctor could never know which, if any, had triggered the cure, and just what in fact the patient had suffered from. As medicine had grown more complex, so the defined edges of all diseases had frayed and shaded into one another. Something like that was forever in danger of happening with computers as their tasks grew more complex and the nature of their response came closer to Webster’s definition of thought: “to form in the mind, to exercise judgment.” As computers developed mysterious malfunctions, computer detectives came into existence with more and more developed instincts for where sneak circuits might occur, where functions could intertwine and paralysis crop up in whole areas of an operation. There was a checklist the astronauts had to go through with every instrument on the Lem, and for the Pings the checklist was detailed. It engaged dozens of switches which produced hundreds of combinations of circuits which in turn offered thousands of possibilities for sneak circuits. For months, Staff Support rooms and every corporation associated with Guidance Control had worked on the anticipation of where and how sneak circuits might occur. No one, however, could be certain—to anticipate every whim of a computer was equal to foreseeing the steps of a virgin whose heart was nymphomaniac—electricity could not run through a multiplicity of circuits without creating a wake of electromagnetisms and interferences whose results were occasionally so bizarre a flight controller could be known to give assent, with unhappy expressions on his face, to the possibility that a computer operator charged with psychic tension on an extraordinary day could also have his effect on the malfunction of the computer. At any rate, the checklist, product of months of work and months of preventive detection, was gone through by the astronauts while circling the moon, and after every item was fulfilled
correctly, every switch properly thrown, a sneak circuit was still not avoided. In the no-man’s-land of electrical hegemony, sneak circuits resided at the very edge of thought. “If we had been supersmart,” said the Flight Director Gene Kranz on another day, “we could have picked up the possibility.”