Borderlands of Science

by Charles Sheffield

  1543: Copernicus proposes the heliocentric theory displacing Earth from its position as the center of the universe.

  1673: Leeuwenhoek, with his microscopes, reveals a whole new world of "little animals."

  1687: Isaac Newton publishes Principia Mathematica, showing how Earth and heavens are subject to universal, calculable laws.

  1781: Herschel discovers Uranus, ending the "old" idea of a complete and perfect solar system.

  1831: Michael Faraday begins his groundbreaking experiments on electricity and magnetism.

  1859: Darwin publishes The Origin of Species, dethroning Man from a unique and central position in creation.

  1865: Mendel reports the experiments that establish the science of genetics.

  1873: Maxwell publishes A Treatise on Electricity and Magnetism, giving the governing equations of electromagnetism.

  1895-7: Röntgen, Becquerel, and J.J. Thomson reveal the existence of a world of subatomic particles.

  1905: Einstein publishes the theory of special relativity.

  1925: The modern quantum theory is developed, primarily by Heisenberg and Schrödinger.

  1928: Hubble discovers the expansion of the universe.

  1942: The first self-sustaining chain reaction is initiated by Fermi and fellow-workers in Chicago.

  1946: The first digital binary computer is built by Eckert and Mauchly.

  1953: Crick and Watson publish the structure of the DNA molecule.

  1996: Evidence is discovered of early life-forms on Mars.

  Is there a pattern here? The most striking thing about this list of dates and events might seem to be the long gap following 1953, since the discovery of Martian life is still highly tentative. We have not seen so long a hiatus for more than a hundred years.

  But is the gap real? In the 1830s, Faraday's experiments on electricity were considered fascinating, but hardly something likely to change the world. In 1865, scarcely anyone knew of Mendel's experiments—they lay neglected in the Proceedings of the Brünn Society for the Study of Natural Science for twenty years. And in 1905, only a small handful of people realized that the relativity theory offered a radically new world-view. (Max Born, later one of Einstein's closest friends, wrote: "Reiche and Loria told me about Einstein's paper, and suggested that I should study it. This I did, and was immediately deeply impressed. We were all aware that a genius of the first order had emerged." Born, however, was himself a genius. It takes one to know one.)

  It also takes a long time to accept ideas that change our basic perception of reality. Remember that Einstein was awarded the Nobel Prize in 1921 mainly for his work on the photoelectric effect, and not for the theory of relativity. That was still considered by many to be controversial.

  Will posterity record the year that you read this book as an annus mirabilis, the marvelous year when the defining theory for the next centuries was created?

  Am I an optimist, if I find that suggestion easier to believe than that we, in this generation, are seeing for the first time in scientific history the wall at the edge of the world? Humans are often guilty of what I call "temporal chauvinism." It takes many forms: "We are the first and last generation with both the resources and the will to go into space. If we do not do it now, the chance will be lost forever." "We are the final generation in which the Earth is able to support, in comfort, its population." "We are the last generation who can afford to squander fossil fuels." "After us, the deluge."

  I believe that science, science new and basic and energetic, has a long and distinguished future, for as far as human eye can see. And I believe that science fiction, which as science draws on contemporary developments but which as literature draws on all of history, will play an important role in that future.

  Certainly, we can envision and write about times as bleak and grim as you could choose; but we can also imagine better days, when our children's children may regard the world of the late twentieth century with horror and compassion, just as we look back on the fourteenth century in Europe.

  Science fiction fulfills many functions; to entertain, certainly—otherwise it will not be read—but also to instruct, to stimulate, to warn, and to guide.

  That is science fiction at its best, the kind that you and I want to read and write. I see no reason why any of us should settle for less.

  APPENDIX:

  Science Bites

  I offered the warning back on Page 1, in the very first sentence: "You are reading an out-of-date book." Science marches on, exploring new territories and expanding older ones every week.

  I knew this, but I didn't think I could do anything about it. Fortunately, I was wrong. Just about the time that Borderlands of Science was reaching the book stores, I was invited to begin a weekly science column for distribution to newspapers and other media (especially on-line outlets).

  There was only one catch. The columns would have to be very short, "science bites" rather than science articles; six or seven hundred words, rather than the six or seven thousand that I am used to. I squirmed at the prospect—what could I possibly say in six hundred words?—but I couldn't deny the logic of the argument. The world speeds up, attention spans are down, so science bites won't catch the fish; all they can do is set the bait, so that an interested reader can follow up with longer articles or books. The good news was that I could write on any subject I liked. And the title of the newspaper column? What else but The Borderlands of Science.

  Here, then, is a little bait, a couple of dozen of those brief articles. All were written after the main body of Borderlands of Science was complete. The Borderland has moved a little farther out. And if you want to see how it is still moving, go online to www.paradigm-tsa.com for more of the weekly columns.

  A.1. The ship jumped over the moon. No matter what Star Trek and Babylon 5 may tell you, moving objects around in space is a tricky business. The Space Shuttle can sometimes do it, provided that it doesn't have to go after anything more than about 300 miles up. The in-space fix of the Hubble Space Telescope was a spectacular success. But if a satellite gets into trouble in a high orbit, thousands of miles from Earth, it's usually beyond saving.

  That's the way it looked in December 1997 when the failure of a rocket booster sent a Hughes communications satellite into the wrong orbit. The spacecraft was supposed to sit at a fixed longitude, 22,300 miles above the Pacific Ocean. Instead it traced a looping, eccentric path, varying widely in its distance from the surface of the Earth.

  Time to give up? It seemed tht way. From its changing position, the satellite could not deliver communications and television in Asia. And although the spacecraft had a small rocket of its own on board, there was not enough propellant to move it directly into the correct orbit. Insurers examined the situation and declared the satellite a total loss. In April 1998, they gave ownership back to Hughes, saying in effect, "Here's a piece of junk way out in space. It's all yours, do what you like with it."

  Hughes engineers did, through a surprising and spectacular idea: Although the satellite's rocket was not big enough to force it directly into the right orbit, it could float the spacecraft out to the Moon. Once there, the lunar gravity field might be used to change the orbit of the satellite. In effect, the spacecraft would get a "free boost" from the Moon, stealing a tiny amount of Luna's vast orbital energy to modify the satellite's own speed and direction.

  The first swing around the Moon was made in May 1998, after which the spacecraft came looping back in toward Earth. The orbit still wasn't right, so another small rocket firing and a second lunar swing-by was made three weeks later. This time the satellite returned close to its desired orbit. A final firing of the rocket engine in mid-June, 1998, did the trick. The spacecraft now sat in a 24-hour circular orbit, just as originally planned, going around the Earth at the same speed as the world turns on its axis.

  It sits there now, drifting a few degrees north and south of the equator every day while remaining close to a constant longitude. Known as HGS-1, it is working
perfectly and ready for use in global communications. More than that, HGS-1 serves as a tribute to human ingenuity. When a space mission in trouble had officially been declared dead, engineers down here on Earth "repaired" it without ever leaving their chairs. Perhaps even more impressive, to anyone who remembers the first disastrous attempts to launch an American satellite: this round-the-moon space shot didn't rate television coverage or a newspaper headline. We've come a long way in forty years.

  A.2. Future cars. I'm a writer, so there's a chance my works will live on. But I agree with Woody Allen, I don't want to live forever through my works. I want to live forever by not dying.

  That presents certain problems. If I—and you—don't die, we will certainly get older. Sixty years from now, without some spectacular medical advance, none of us will look or feel young. The retina of a 75-year-old has only 10 percent of the sensitivity of an 18-year-old. By age 75, we are at least a little deaf (particularly the men). The range of mobility of our neck and shoulders is down, and our reaction times are slower. However, if today's 70- and 80-year-olds are anything to go by, we'll insist on one thing: we want to drive our own cars. It's part of our independence, our ability to look after ourselves.

  Let's put that together with another fact, and see where it takes us: People are living longer, and the US population is getting older. In 1810, there were only about 100,000 people over 65. By 1880 it was close to 2 million. By 1960, 16 million, and today it's over 30 million. In 2030 it will be near 60 million. And most of these aging people—remember, that's you and me—will still want to drive their cars.

  We will need help, and fortunately we will get it. Auto manufacturers who study ergonomics—the way that people operate in particular situations—are already taking the first steps.

  The driver doesn't see or hear too well? Fine. The car provides a "virtual reality" setting. Actual light levels outside the car will be changed, so that what the driver sees compensates for loss of visual sensitivity. The driver will receive an enlarged field of view without having to turn very far, so as to compensate for decreased head and neck mobility. The speed of reaction of the driver will be improved using servo-mechanisms, just as today the strength of a driver is augmented by power steering.

  These are all, relatively speaking, easy. They can be done today. Most older drivers already wear glasses. We simply replace them with goggles that present virtual reality views of the surroundings. The driver should hardly notice, except to remark how much clearer everything seems.

  At the same time, the car will do more things for itself: monitoring engine temperatures, stresses, loads, and driving conditions. Rather than presenting this information in the "old-fashioned" way, through dials and gauges, the car's computer will report only when something is outside the normal range.

  More complex, and farther out in time, comes the involvement of the car's control systems in real-time decision making. Here, the automobile not only senses variables from the environment, it also interprets the inputs, draws conclusions, and recommends actions (ACCIDENT FOUR MILES AHEAD; SUGGEST YOU LEAVE FREEWAY AND TAKE ALTERNATE ROUTE. SHALL I MAKE ADJUSTMENT AND ESTIMATE NEW ARRIVAL TIME?). Or, in emergency, the car's computer will initiate action without discussion. A human cannot react in less than a tenth of a second. A computer can react in a millisecond. The difference, at 60 miles an hour, is about 10 feet—enough to matter.

  These changes to the automobile are more than probabilities; I regard them as future certainties. My job, and yours, is to be around long enough to enjoy them.

  A.3. Making Mars. A hundred years ago, Mars was in the news. H.G. Wells had just published his novel, The War of the Worlds, and everyone seemed convinced that there must be life on the planet. Astronomers even thought they had seen through their telescopes great irrigation "canals," showing how water was moved from pole to pole.

  Today, Mars is a hot topic again. Some scientists believe they have found evidence of ancient Mars life in meteorites flung from there to Earth. Others say, forget the ancient past. Mars is the place for life in the future—human life. Let's go there, explore, set up colonies, and one day transform Mars so that it is right for people. Mars has as much land area as Earth; it could be a second home for humanity.

  Sounds great. NASA ranks Mars high on the list of its priorities. Can we make another planet where humans can live, work, raise families, and have fun? How easy is it to change Mars so it is more like our own planet?

  In a phrase, it's mighty tough. Mars has plenty of land. What it does not have are three things we all take for granted: air, water, and heat. Making Mars more like Earth—"terraforming" the planet—requires that we provide all three.

  Heat should be the easy one. We can load the thin atmosphere of Mars with CFC's, "greenhouse gases" currently in disfavor on Earth because they contribute to global warming. As the temperature rises, solid carbon dioxide held in the Mars polar ice caps will be released into the air, trapping more sunlight and adding to the warming process. The Mars atmosphere, currently only about one percent as dense as ours, will thicken. At the same time, the temperature will rise enough for water, held below the surface as permafrost, to turn to liquid as it is brought to the surface. Recent estimates suggest enough water on Mars to provide an ocean three hundred feet deep over the whole surface.

  When the warming process is complete Mars will have heat, water, and air. Unfortunately, that air will be mostly carbon dioxide. Humans and animals can't breathe that—but growing plants rely on it, taking it in and giving out oxygen. The key to making breathable air on Mars is through the import of Earth plant life, genetically engineered to match Mars conditions.

  Now for the catch. If we started today, how long would it take to transform Mars to a place where humans could survive on the surface? In the best of circumstances, assuming we use the best technology available today and make this a high-priority project, the job will take four or five thousand years.

  That's as much time as has elapsed since the building of the Egyptian pyramids. The technology available to our far descendants is likely to be as alien and incomprehensible to us as computers and genetic engineering and space travel would have been to the ancient Egyptians. Maybe we ought to wait a while longer before we start changing Mars.

  A.4. Close cousins: How near are we to the great apes? A visit to the monkey house at the zoo is a sobering experience. We stare in through the bars. Looking right back at us with wise, knowing eyes is someone roughly our shape and size, standing like us on two feet, perhaps pointing at us with fingers much like our own and apparently laughing at us. He bears an uncanny resemblance to old Uncle Fred. Maybe we should look twice to make sure who is on the right side of the bars.

  It is easy to believe that of all the creatures in the animal kingdom, the chimps, gorillas, and orangutans are nearer to humans than any other. The question is, how close?

  A generation ago, we could offer only limited answers. We were different species, because inter-breeding was impossible. As for other similarities and differences, they had to be based on the comparison of muscle and bone structure and general anatomy.

  Now we have new tools for the comparison of species. The complete genetic code that defines a gorilla is contained in its DNA, a gigantic long molecule organized into a number of long strands called chromosomes. Moreover, every cell of a gorilla (or a human) contains the DNA needed to describe the complete animal. Given a single cell from a chimp and a cell from a human, we can take the DNA strands and do a point-by-point comparison: the structure is the same here, different there. The extent to which the two DNA samples are the same is a good measure of the closeness of the two species.

  This analysis has been performed, and the results are breathtaking. Humans and chimps share more than ninety-eight percent of their DNA. Each of us is, in an explicit and meaningful way, less than two percent away from being a chimp.

  The same exercise, carried out with DNA from orangutans, shows that humans are rather less closely
related to them. As we consider other animals, everything from a cheetah to a duck to a wasp, we find that our intuitive ideas are confirmed. The differences between our DNA and those of other creatures steadily increases, as the species become more obviously "different" from us in form and function. DNA analysis tells us that we are more like every other mammal than we are like any bird, and we are more like every bird than we are like any insect.

  We can use this and other information to estimate how long ago different species diverged from each other. Humans and chimps have a common ancestor which lived roughly five million years ago. Humans and gorillas diverged at much the same time, as did chimps and gorillas from each other. We and the orangutans parted ancestral company farther in the past, about twelve to fifteen million years ago.

  Five million years may sound like a long time, but there has been life on Earth for more than three and a half billion years. We and the great apes separated very recently on the biological time scale, and we really are close cousins. It should be no surprise that we feel an odd sense of family recognition when we meet them.

  A.5. Breathing space. How many can Earth hold? Stuck in rush hour traffic on a hot day, you sometimes wonder: Where did all these people come from? You may also mutter to yourself, Hey, it wasn't like this when I was a kid.