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The fate of human civilization will depend on whether the rockets of the future carry the astronomer’s telescope or a hydrogen bomb.
—SIR BERNARD LOVELL, THE INDIVIDUAL AND THE UNIVERSE (1959)
Murder most foul was committed one quiet summer’s evening in a leafy South London park, but no one happened to notice it—not until the moment a fashion photographer, working quietly in his darkroom, enlarged and enlarged an otherwise innocent black-and-white image that he had taken in the park a while before and saw, or thought he saw, hidden in the trees, a hand with a gun and a body in the grass.
His film stock was grainy, and the enlarged pictures were blurred, but the images, all part of the story line from Michelangelo Antonioni’s Oscar-nominated movie, Blow-Up, remain to haunt us to this day, and though the movie was about very many more things than murder, they serve as a reminder of the unassailable power of the camera to render random moments, sometimes quite inadvertently, into permanent historical truth—as I have lately come to know.
I work in an old timber-framed barn, a onetime granary built in upstate New York back in the 1820s. It was a tumbledown ruin when I bought it, and so I had its posts and beams trucked down to where I live, in a remote hamlet in the hills of western Massachusetts, and saw it rebuilt there in the summer of 2002. The internal arrangements of this modest little building allow for someone to look down from an upper gallery onto the confused mess that is my desk, fifteen feet below.
Because the barn is quite old, and because the phenomenon of breathing new life into old and decaying farm structures and renewing them as a living part of today’s New England scenery was thought interesting, a photographer turned up one afternoon. He said he was working on a book on barn restorations, and once I happily gave him free rein, he spent some hours taking pictures, including some, from the gallery, of my paper-strewn desk below.
The images duly appeared in a rather handsome coffee-table book about the barn-rebuilding phenomenon. As a courtesy, I was duly sent a copy. I spent an evening admiring it (though, in truth, mostly envying barns of far greater grandeur than my own modest granary-that-was) before filing the volume away on the shelves and thinking no more of it.
Except, it turned out that someone quite unknown to me bought a copy of the book, too, and professed a liking for the little study structure he came across on page 61. Whether he was a fan of Blow-Up, I never knew, but he thought he might be able to find out just who it was who lived and worked there.
For on the desk in the picture was a copy of the New York Review of Books, half-covered with other litter: magazines and books and papers. The purchaser of the barn book espied that at the lower-right-hand side of the Review was an address label, small and barely noticeable to most. But to this fellow, it provided a possible source of information—if, that is, the lens that took the photograph was good enough for the label to be read when greatly magnified.
So he cut off the front cover of the Review, separating it from the other mess on the desk, and subjected it to ever-increasing degrees of magnification. The small and indistinct letters duly become ever larger and larger—until, even though the pixels of the printed image made for some eventual confusion, after four or five iterations of expansion, my name and address became legible. And all of a sudden, this mystery man knew who it was, most probably, who owned or lived in or made use of the barn. He got in touch.
And though the process sounds at this remove somewhat Peeping Tom–like, even faintly sinister, it turned out not to be so at all—the inquirer was entirely pleasant and most interesting; determined, slightly obsessive, maybe a trifle “on the spectrum,” as is said today. He was a retired vascular neurosurgeon. He was a keen photographer. He was endlessly, preternaturally curious—polymathic, one might say—and he was fascinated most especially with the capabilities of precise optics in allowing for forensic detection, and with all the intellectual satisfaction that this could bring him.
AS FOR MOST English schoolboys—for most schoolchildren everywhere, I daresay—lenses played a not insignificant part in my life. My first (most of which back in the 1940s were made of glass, plastic in those days being hardly good enough, and polycarbonates almost unknown) were all double-sided convex magnifiers. The first such lenses were used for trivia and for mischief: for examining tadpoles and peering at insufficiently detailed pictures in naturist magazines, for starting campfires, or for waking other boys foolishly unwary enough to fall asleep in the sunshine—a brief focus of sunlight on a bare arm would bring the deepest sleeper fully awake in seconds.
Better-quality lenses became more important to me when I was about ten and I became fascinated by phasmids, or stick insects. I would breed them—their homes were my mother’s old Kilner jars filled with privet leaves from our garden hedge—and sell them to my classmates, threepence a time. But stick insects often develop strange microscopic problems—they sometimes find themselves unable to shake from their feet (of which, being insects, they have six) the egg cases from which they are born. Microsurgery, involving a needle, a fine tweezer, and my trusty times-ten magnifier, usually did the trick.
Then came gathering maturity. I went on to collect stamps, and amassed a collection of several magnifiers: a square-shaped lens to view the smaller stamps in full, a jeweler’s loupe that I screwed into my eye and used for counting perforations and for spotting franking mishaps, and a heavy glass implement that looked like a paperweight but that, when I swept it across an album page, would let me display my collection, duly enlarged, to any curious passerby.
Precision optics (which generally meant expensive optics, and consequent pleas to the parents for funds) became of interest only when I hit fourteen or so, and needed, as I saw it, a microscope. Money was always short, but by rooting through secondhand shops and street barrows, I eventually acquired a range of those, too (made by firms such as Negretti and Zambra, Bausch and Lomb, Carl Zeiss), all in handsome wooden cases with slots for the changeable eyepieces and smaller slots for the magnifying lenses. I recall that there was a 1950s version of today’s pixel envy, which had youngsters arguing over whose instrument offered the highest magnification. Given that we were looking at samples of pond water to spy out examples of Daphnia, or seawater to find those little pointed slivers of Amphioxus, and had neither the knowledge nor the equipment to probe much further into the world that Galileo and van Leeuwenhoek had bequeathed to us, there was little value in going beyond three-hundred-times magnification. I rather think some of my lenses allowed magnifications of a thousand, which was useless to my clumsy hands, which would knock something out of the field of view in an instant at what seemed like rocket speed. Some adolescent members of the school microscope club claimed to have seen their own spermatozoa, which struck me back then as both doubtful and disgusting, and also requiring an improbably handsome degree of magnification.
And then I bought a camera. A Brownie 127, first of all, with its plastic Dakon lens—a fixed aperture of f/14,* a focal length of 65 mm, and a fixed shutter speed of a fiftieth of a second. I would take the rolls of exposed film to a small drugstore in the Dorset market town of my boarding school, and the chemist there who developed and enlarged the black-and-white images would encourage me, thinking my work had some small merit—or else, more probably, trying to get me to buy some of his small selection of cameras. I eventually caved in to his flattery and bought a 35 mm Voigtländer† camera from him, a decision that sent me on a road that progressed over the years through a long trail of cameras that all used 35 mm film, most of them initially made in Japan by companies such as Pentax, Minolta, Yashica, Olympus, Sony, Nikon, and Canon.
Finally, one day in 1989 in Hong Kong, where I was living at the time, a young Cantonese salesman persuaded me that what I really needed was a quiet, compact, reliable, super-precise, and very sturdy 35 mm film camera that would be suited to my rather unpredictable life as a wandering foreign correspondent. A Leica M6, he said, and equipped with a remarkable lens, a (then-unfamiliar to me, but already legendary to those in the know) little black cylinder of robust delicacy, the phenomenally light and extraordinarily fast confection of air, glass, and aluminum known as the 35 mm f/1.4 Summilux.
That little lens stayed with me, performing journeyman work for the newspapers and magazines for which I worked, for more than a quarter of a century. It then went on to serve briefly on a newer and very different Leica body that I acquired much later. Eventually, I succumbed to the advice of my betters and bought that lens’s natural successor, the 35 mm f/1.4 Summilux ASPH, which had an aspherical lens with what is called a floating element to it—regarded at the time of this writing as perhaps the best general-purpose wide-angle camera lens in the world, and probably the classic popular exemplar of high-precision optics.
There are certain ineradicable truths in the world of optical hyperprecision, and one of them, by near-universal agreement, is that the best Leica lenses are and long have been of unsurpassed quality, and deservedly represent the cynosure of the optical arts. The century-long arc of progress began with the moment in 1913 when Oskar Barnack—legend has it that he was asthmatic, and needed a lightweight camera—made both the first 35 mm film and then the first-ever Leica camera, called the Ur-Leica. It led to the creation of the supremely good lenses of today, a trajectory of progress in optics that mirrors much of the progress of precision more generally, even though using materials that, unlike most of the devices in this account, are invariably, and for the best results, transparent.
The optical journey itself begins almost a century earlier still.
If humankind’s acceptance of light and dark began the moment the first eye was opened, or blinked, or shut, then the first questioning of optical phenomena probably started soon thereafter. The nature of shadows, of reflections, of rainbows, of the bending of sticks in pools of water, of shades and tint and hues of color—all would have come first, and then later there would have been considerations of the action of mirrors, of burning glasses, of the twinkling of stars and the steady light of planets, of the anatomy of the eye—all inquiries that are recorded in writings (Greek, Sumerian, Egyptian, Chinese) from at least three thousand years ago. Euclid’s Optics was written in 300 BC, and though it is mainly a treatise on the geometry of angular perspective, and the belief that light to the eye is created by an ether-like substance called “visual fire,” it laid the groundwork for Ptolemy’s theories of five centuries later, brought some detachment and sophistication to the science of astronomy, and advanced theories of refraction and reflection that have not changed much to this day.
The prototype Ur-Leica, fashioned in 1913 by the Leitz employee Oskar Barnack. It was small, light, with a near-silent shutter, and a 24 × 36 mm film format.
Surgery on eyeballs had already revealed the existence of a lens, a perspicillum, which, from its secure position at the front of the iris, magnifies all that it sees. It was a Swiss doctor who first displayed the lens of the human eye, and gave it the name that Romans had for centuries given to the small pieces of glass that the optically afflicted used for helping with their poor vision: perspicillum in later years denoted either a telescope, to see distant things up close, or crudely made and ad hoc spectacles, which helped make close things appear sharply in focus and the illegible capable of being read.
Even though Ernst Leitz famously helped his Jewish employees to leave Germany in droves, his cameras were much used by Hitler’s military. Here are a pair of IIIcs worn by a Kriegsmarine seaman.
Nero, myopic in more ways than one, was said to have watched gladiatorial contests through a conveniently curved emerald. The first true spectacles appear in images drawn in Italy in the thirteenth century, with simple lenses maybe, but life-changing for those who required them or for uses that allowed for the discovery of the distant unknown. Then came Galileo, and Kepler and Newton, and theories of light became ever more complex, and the exactitudes of geometrical optics took over from a hazy belief in visual fire; and then telescopes and binoculars and microscopes were made; and Benjamin Franklin reputedly created bifocal lenses, the glass more convex in his spectacles’ lower half for reading and less rounded above a metal spacer, and so allowing for viewing at distance, in the early 1780s or, maybe, according to new research, as much as fifty years before that. Finally, in due time, with the realization of light sensitivity among various families of chemicals, the scientist and inventor Nicéphore Niépce snapped the first photograph and preserved one modest illuminated moment (even though it was a moment no less banal than its title, A View from the Window at Le Gras) for all time.
Snapped is hardly the word. Niépce used a camera obscura, at the back of which he mounted a pewter plate he had painted with a thin layer of a kind of bitumen he had discovered would harden upon exposure to light, becoming less hard in those places where the lens directed the lesser light and firmer where the illumination was intense. The asphalt was also selectively soluble—it could be washed away with a mixture of lavender oil and white gasoline—and Niépce realized with decisive logic that the firm parts would likely be more resistant to washing and the softer parts easily swept away. So, using this kind of chemical reaction to light and dark, Niépce took a photograph. It was a crude picture of a rooftop terrace made of blocks of stone, with a grove of trees at center stage and, across slightly to the right, a distant horizon with steeples and vague outlines of hills. It is barely recognizable, yet it is undeniably a vague image of just what his primitive little camera saw.
The picture was taken in the summer of 1826, in an east-central French village named Saint-Loup-de-Varennes (now a place of pilgrimage among the world’s photographers), and with an exposure time of many hours, perhaps even many days. There is nothing either precise or accurate about the image, though it has a strangely ethereal beauty to it, and is viewed with great and deserved reverence in a vitrine in a much-protected vault at the University of Texas at Austin.
We know less than we might wish of the kind of lens Niépce employed on that long-vanished sultry summer’s day—was it made of rough or polished glass, of ground crystal, or of a piece of amber found in a riverbed? We can suppose, but we cannot be sure. It was certainly fixed solidly in the camera box, and was certainly composed of just a single element, a single transparent entity. It was probably lemon shaped, convex on both sides. From examining the image that resulted, we know that it suffered from all the classic limitations of early photography: an inability to focus being one, an inability to capture sufficient light another, with distortions at the edges and at the sites where more light was falling. It certainly had no pretensions to being precise. Yet it is quite rightly a piece of deliberate creation, the haunting nature of its imagery a foreshadowing of a whole new art form to come.
Since Niépce’s pioneering work, lens designers have discovered a host of technical problems that can conspire to spoil a photographic image: chromatic aberration, spherical aberration, vignetting, coma, astigmatism, field curvature, and problems with bokeh* and the so-called circle of confusion being among the best known. They have therefore experimented endlessly to produce compound lenses of great complexity that correct for all these trials but that are at the same time fast and light and pure and true, and that contrive to make images that are as close to technical perfection as it is possible to imagine. The 134-year journey from Niépce’s creation in 1826 to the designers and makers who created Leica’s first 35 mm f/1.4 Summilux lens in 1960 offers a demonstration of a great optical trajectory, from simplicity to high precision, marking a passage in time from which all images were necessarily vague, to today, when, if desired, all can be razor sharp—not necessarily more beautiful, but forensically useful, in which highly detailed and accurate records of moments in time can be produced and preserved, and which, because of their accuracy, are entirely amenable to being blown up many, many times.
The way in which this was achieved has as much to do with mathematics as it has to do with materials. Mathematical concepts such as angles are crucial—angles of refraction, for example, or angles of dispersion, both of which are determined in large part by the kind of glass used in a lens. Refraction is a measure of how much a lens bends light, dispersion of how varied are the angles at which a lens refracts light of different wavelengths (that is, of different colors). Early lens designers did their best to limit spherical aberration and chromatic aberration (the very visible consequences of too much refraction and too much dispersion) by the brilliant idea of grinding two lenses of different materials such that they fitted exactly together—and in doing so, in the late 1830s, they created the first kind of multi-element lenses.*
The multi-element arrangements that followed, and that have dominated fine lens making ever since, began primitively enough, with just the two lenses pressed together. In these early examples, one lens would be made of a glass with specific refractive properties, such as so-called crown glass, which has a very low refractive index; and the other would be made of so-called flint glass, which has a very different chemistry, a high refractive index, and very low dispersion. Grind them into complementary shapes and press and cement the two together, and you come up with what is called a doublet.
The illuminated image whose reflected rays pass through this doublet are then focused onto the film at the back of the camera in a manner that will be much more disciplined, focused, and lifelike than the fuzzy, blurred-edge, and randomly aberrant imagery previously offered by single-lens cameras of yore. The crown glass lens deals with one problem, the flint glass lens with another—and the two together are ground so perfectly that, optically, they act as one, with one physical effect on the light, variously now tinkered with by its two components.
Multi-element confections of one kind or another have dominated good-quality camera lens designs ever since. Optics designers are today rather like orchestral conductors, maestros who marshal and corral morsels of carefully shaped and exquisitely ground glass of varying chemistries and optical properties into configurations that will provide the most harmonic and pleasing management of light for the task the lens is designed to perform. Lens geometries are infinitely variable, lens materials even more so—tiny additions of rare earths change the dispersion and the absorption and the refractive abilities of transparent materials, while certain nonglass materials (germanium, zinc selenide, fused silica) perform particularly well with certain kinds and wavelengths and intensities of light.
The job of a lens is to capture the light and present it to the camera and the film or the sensor it holds. As cameras and films and sensors became ever more able (allowing for higher shutter speeds and finer grains and, in the digital world, ever more pixels), the manufacture of light-presenting lenses became ever more demanding, the arrangement of glasses within ever more intricate. Portrait lenses, for example, had one kind of configuration: an early kind had four lens elements, two cemented together, two grouped together but with air sandwiched between them. Lenses designed for capturing photographs of landscapes, for their part, had very different arrangements, as did wide-angle, close-up, telephoto, macro, fish-eye, and zoom lenses. Indeed, some variable zoom lenses have as many as sixteen elements, some of them movable, some of them fixed, some stuck firmly together, and some separated by distances large enough, but nonetheless very accurately measured, for the resulting lenses to be of bewildering and barely manageable lengths, often needing a tripod support of their own, with the camera body a mere bagatelle fixed to one end.
Leica—the name is a blend of the company founder’s surname, Leitz, and his product, a camera—entered the field of exact optics in 1924. The inventor of the first 35 mm camera, Oskar Barnack, whose two Ur-Leicas were built in 1913 and whose O-series production camera was offered to the public in 1925 (the interlude being due, of course, to the Great War), was incredulous at the quality of the early lenses. The O series was equipped with a lens designed by a long-forgotten optical genius named Max Berek. It had five glass elements (a cemented triplet and two singlets), and when Barnack saw the results, a clutch of eight-by-ten-inch prints sent to him in the mail, he dismissed them out of hand: they couldn’t possibly be the enlargements of the 35 mm images he had been promised. Yet, of course, they were—blown up tenfold and losing none of their crispness in the process. The lens that took the images went on the market as the 50 mm Elmar Anastigmat, and it remained a classic for generations, and is a priceless collector’s item today.
And down the years, so the lenses processed, all with code names ineradicably linked with Leica: the Elmax, the Angulon, the Noctilux, the Summarex, the too-numerous-to-count Summicrons, and the bijoux of the family: the three focal-length superfast lenses (35 mm, 50 mm, and 75 mm) that were given the code name Summilux, and all of which were designed to offer the most stringent accuracy even at their widest aperture of f/1.4.
For the making of all these, the common Leica standards were unparalleled. Whereas most camera makers work today to an industry standard of 1/1,000 of an inch, and with Canon and Nikon working their mechanicals to a supertight 1/1,500 of an inch, Leica bodies are made to 1/100 of a millimeter, or 1/2,500 of an inch. And with lenses, the tolerances are even tighter. The refractive index of Leica optical glassware is computed to ±0.0002 percent; the dispersion figures (the so-called Abbe numbers) are measured to ±0.2 percent, against an industry-agreed international standard of 0.8 percent. And the mechanical polishing and grinding of the lenses themselves are performed to one-quarter lambda, or one-quarter of the wavelength of light, with lens surfaces machined to tolerances of 500 nanometers, or 0.0005 mm. And with the aspherical lenses that cut so markedly down on the tendency at wide apertures to display spherical aberrations, machining of the glass surfaces is performed down to a measurable 0.03 micrometer, or 0.00003 mm.
The lens I now have as successor, the mighty miniature classic 35 mm f/1.4 Summilux, ticks all these boxes, insofar as it now comes with one aspherical lens element that has, in a very recent iteration known as the aspherical FLE, four of its nine elements closest to the camera body floating, free to travel together as one within the lens structure, giving the most memorably good results. This lens has become perhaps the best-regarded wide-angle piece of optical glassware ever made, by anyone: the reviews have been stellar.
To hold one of these lenses (a scant ten ounces of aluminum, glass, and air) is to hold almost the most precise of modern consumer durables—with one notable and rather obvious exception: the smartphone. Within that particular handheld device (as I shall outline later) is a sturdy mix of mechanical exactitude, the various component parts finished to the severest of tolerances. Yet there is also, and essentially, a mass of electronic precision to it, a gathering of myriad components where no moving parts are present to interfere with what is designed to be their constant perfect performance. The making of the circuitry that runs the smartphone, and similar versions of which run other devices big and small that profoundly affect so very much of today’s lives, takes the concepts of accuracy and precision into a whole new realm. But that is for later.
MECHANICAL PRECISION, AT this high and demanding level, can on occasion stumble, however—tiny errors can be made; they can accumulate, resonate, and harmonize to become major errors, after which they can become the origin of problems that the designers may never have supposed or imagined.
For instance, those workers in Hucknall, Nottinghamshire, who in 2009 incorrectly machined the tiny metal tubes made to lubricate the turbine section of a jet engine never would have imagined that, a year later, because of their minuscule mistake, a fire would break out, the engine would destroy itself, and the lives of almost 470 people would be briefly in the balance a mile up in the sky above Indonesia.
The kind of tolerances demanded in modern precision devices allow essentially for no errors, but insofar as human beings are still involved in the manufacturing of precise things, human failings do occasionally creep into the process. Possibly the most recent classic example of an imprecise human failing intersecting with a mechanism made for a precise and uninhabited world was that exposed for all to see with the launch, and then the failure and, finally, the great success, of the Hubble Space Telescope.
“ASK ANY PERSON the name of a playwright,” remarked Mario Livio, a NASA astrophysicist and senior scientist on the telescope project, “and most of them would say Shakespeare. Ask them the name of a scientist, most of them would say Einstein. Ask the name of a telescope—they will all say Hubble.”* There is a distinct public reverence for this telescope, in part because of the sheer magnificence of the images it has sent back to Earth from space in recent years. To some of us, though, Hubble is perhaps also regarded fondly because of its vulnerability, because of its troubled story, its phoenixlike rise from the ashes of its awful beginnings.
The Hubble Space Telescope was launched and then placed into orbit 380 miles above Earth on April 24, 1990. After its mirror was found to be flawed, it was repaired in space in December 1993. The Hubble has since performed near-flawlessly, sending back countless captivating images of interstellar space.
It was placed gently into orbit, 380 miles above Earth, on April 24, 1990. At the time of its launch, Edwin Hubble, America’s great deep-space astronomer, who was the first to suggest that the universe might be expanding, who examined the universe beyond our own pitifully small galaxy, and after whom the telescope is named, had been in his grave for almost forty years. This in-space observatory, at launch time more than a quarter century in the planning, was in essence a project to push still further inquiry into the state of faraway stars and galaxies and nebulae and black holes.* The device was less a memorial to him than a continuation of his work.
The orbiter Discovery took the Hubble up into space, to a place well above the distortion and pollution of Earth’s atmosphere and comfortably away from the harsher pulls and tugs of geomagnetism and of gravity. It was the seventh flight of this particular workhorse of a space shuttle—the orders were for a short (five-day) in-and-out, drop-it-and-leave-it mission. The flight was designated STS-31, and, despite the numbering, was the thirty-fifth mission of NASA’s five reusable Space Transportation System vehicles—except that, at the time of the launch, the number of orbiters was down to four.
And because of that grim arithmetic, those who watched the shuttle launch on that warm Florida spring morning were more white-knuckled than usual. Four years before, the sister orbiter, Challenger, had exploded seventy-four seconds after takeoff, killing everyone aboard. After three years of memorials and investigations and repercussions and modifications, NASA decided that Discovery would be the vehicle to perform the first post-accident flight. Her mission, then, in September 1988, was designed as much for confidence building as it was for the execution of major science. The nation breathed a collective sigh of relief when the launch in Florida, the four subsequent days spent soaring around the world, and the then-picture-perfect landing in California all went without incident.
Discovery flew again, twice, in March and November 1989, by which time the country had become largely convinced that the problems that had brought down Challenger (a rubber seal that had stiffened in the subzero weather of the midwinter launch day and caused fuel to leak from the solid rocket booster) had been solved. Still, this STS-31 was an extremely high-value mission: the Lockheed-built telescope and its Perkin-Elmer Corporation optics, snugged safely away in the cargo bay, had already cost the taxpayers around $1.8 billion. There was much consequent anxiety before the launch. This anxiety barely diminished even after the successful liftoff. Indeed, the pressure was unrelenting until the moment the next day when the crew used Discovery’s Canadian-made robotic arm to lift the bus-size payload out of the hold; set up its solar panels and telemetry and radio aerials; switch it on, as it were; and finally let the first of NASA’s so-called great observatories free-float into orbit.*
Hubble, enormous during its construction (the size of a five-story house) but minuscule in appearance when floating in the immense nothingness of space, is perhaps not the prettiest of sights. There is something rather awkward, almost teenager gawky, about its appearance—like a once-chubby, silver-coated boy who has suffered a sudden growth spurt and who floats along on his own looking, his mother unable to afford new clothes for him, rather wrinkled and ungainly and uncomfortable with his new shape. Moreover, the hinged lid at one end, which admits the light into its main tube, looks awkward, too—so much like the open top of a kitchen garbage can that you rather expect a foot pedal to be protruding from somewhere, keeping it open all the while. Instead of pedals, there are solar panels, squared off and able to furl and unfurl as the temperature varies depending on the telescope’s attitude and position.
It is wanting in prettiness maybe, but its two builders and NASA, their customer, knew it to be an extremely powerful piece of kit. In many ways it was a quite simple telescope, a so-called Cassegrain reflector, well known to any amateur backyard stargazer, with a pair of mirrors facing each other—the primary mirror gathers the light and reflects it to the smaller, secondary mirror, which then reflects it back once again, through a hole in the center of the primary and to a variety of observing devices (cameras, spectrometers, and detectors of various wavelengths from ultraviolet all through the visible-light spectrum and into that of the near-infrared). The detectors were packed into telephone booth–size boxes arranged tightly behind the primary mirror, and from which the gathered data would then be beamed as telemetry signals back down to Earth.
The specific design of Cassegrain used in the Hubble telescope involved the use of a particular mirror shape—they were called hyperbolic reflectors—that specifically reduced the chance of two types of aberrations in the image, the comet trail–like aberration known as coma and the edge-of-lens error known as spherical aberration. And as Hubble settled itself into space that May (once Discovery had fired her braking thrusters and dropped out of orbit and spiraled her way down earthward to leave the telescope quite silent and alone), the device, with all its optical distortions and aberrations duly thought of, anticipated, and averted, seemed richly pregnant with astronomical potential.
Except that, six weeks later, an unanticipated nightmare began to unfold, an unimagined nightmare—for this was no Challenger, where frantic engineers far away, who knew of the risks of launching in freezing weather, tried desperately to cancel the flight. In Hubble’s case, all was blissfully normal, everyone lulled into a state of contentment—and, as it happens, hubris.
All began routinely. Three weeks after the telescope had reached orbit, on May 20, by which time all were confident that it had cooled itself from the warmth of the Florida beachfront to the ambient temperature of its new surroundings, Mission Control sent out a signal to unlatch the hinged front door to the optics.
Hubble was now open for business. The first light from a million stars—and this was the way the moment was named, the First Light—flooded into the barrel of the telescope. From there, it headed toward the primary mirror and made its reflective journey back and forth until, ultimately, it fed itself into the detectors and became the data that were so eagerly awaited by the watchers of the skies on Earth at the Space Telescope Science Institute at Johns Hopkins University in Baltimore, far down below. The transmissions were perfect. Data were streaming down, just as they should. An astronomer named Eric Chaisson inspected the incoming images, and then, suddenly, as he examined what he saw, he felt, as he put it, “a total deflation in my gut.”
Something was horribly, horribly wrong. Everything was blurry.
Two weeks later, Edward Weiler, who at the time was chief scientist for the Hubble program at NASA’s Goddard Space Flight Center, thirty miles away, was basking in the apparent success of the early stages of the mission. But then he received an alarming telephone call. It came from one of his colleagues at the science control room in Baltimore. Try as they might to improve matters, the panicky-sounding scientist there told Weiler, every single picture that had been beamed down from Hubble was totally out of focus (except, by some cruel trick, the very first, which seemed very sharp indeed).
They had tried for days, not daring to report the news, to fine-tune the images by moving the secondary mirror by infinitesimal amounts, to tease out a picture from the primary mirror, which was sharp and clear. But while most of the astronomers in the control room agreed that the image qualities they acquired were as good as or better than their equivalents from ground-based telescopes, they were not nearly as good as they should have been. Indeed, not even that was true; it was wishful thinking. The brutal truth was that not a single one of the pictures could be coaxed into a usable degree of sharpness. Each one of them was a grave disappointment. They were worthless, useless. The mission, by all accounts, seemed all of a sudden to be judged an abject failure.
The ghastly news was broadcast to the world on June 27, 1990, two months after the launch. The vision of a gathering of NASA bureaucrats in their business suits, all sporting long faces of gloom (Ed Weiler, blond and in those days quite cherubic, as downcast-looking as the rest of them), lined up to face a corps of incredulous reporters, each of the scribblers holding an image of interstellar wreckage before him or her, will linger long in the memories of all who watched the awful moment of admission. It was all true, the gathered men said, some of them barely able to get the words out. The eight-foot-diameter primary mirror of the telescope, though at the time the most precisely made optical mirror ever built, appeared to have had its edges ground too flat.
It was out by only the tiniest amount, a fiftieth of the thickness of a human hair, but that was enough to wreak optical devastation. The coma and spherical aberration caused by this one tiny mistake rendered almost all the observations valuelessly befuzzed, with distant galaxies looking thick and edgeless, like marshmallows; stars looking like powder puffs; nebulae, like the merest patches of random discoloration. Images as mediocre as this might as well have been gathered by someone with an eight-inch telescope in a smoky backyard in Ohio. Indeed, there seemed no need to have spent almost two billion dollars and twenty years’ worth of the labor of men and women in America and Europe (for this was a European Space Agency venture as well as NASA’s) and beyond.
The press was viciously unkind. Many agreed that the Hubble was a device no better than the infamously unpopular Ford model the Edsel. Maybe the telescope had been designed by the myopic cartoon character Mr. Magoo. Lemons in space were spotted by many newspaper cartoonists, as was static, the television postbroadcast snow being all that NASA seemed to have discovered, its meaninglessness filling the Hubble-known universe. NASA appeared to be in the business of building “technological turkeys,” said one angry Maryland senator. The optical catastrophe may have killed no one, but in terms of national embarrassment and humiliation, the error was reckoned by some of the more excitable politicians to be on a par with the crash and fire of the Hindenburg and the sinking of the Lusitania.
Indeed, in the view of some more rabid legislators, who, after all, held the NASA purse strings, the ruined performance of what was the costliest civilian satellite ever built—and there were now other mistakes showing themselves: faults with the solar arrays made the whole telescope shake and shimmy, lowering expectations for much serious and successful science—put the future of the entire agency at risk. Only four years before, Challenger had exploded because of agency ineptitude. Now this. Twenty-five thousand NASA employees, uncounted thousands of contractors and suppliers—all suddenly seemed to have their futures on the line.
It turned out to be all down to one company, at the time called the Perkin-Elmer Corporation, which was based in Danbury, Connecticut, ninety minutes’ drive north of New York City. The firm had ever since the late 1960s ground the mirrors and made the cameras for a series of highly classified spy satellites. It was a well-experienced major player on “the dark side,” that mysterious shadowland of research and manufacturing for the American military, whose role in all things precise is acknowledged but seldom spoken about in detail. A windowless cement building on a hill outside Danbury housed the polishing and grinding machinery that had for years enabled the army and the navy and the various spy agencies to look down from on high into forests and fields and bases and houses all over the world, and gain knowledge without anyone below ever knowing they were doing so.
Come 1975, and Perkin-Elmer won a new contract: seventy million dollars, a deliberate lowball bid,* to shape and grind and polish the primary mirror of a giant new telescope. The enormous blank glass disk was delivered from the Corning glass factory in the fall of 1978. Right from the start, the auguries were none too good. A quality-control inspector almost fell onto the glass, saved only when an alert colleague grabbed his shirttail. The joining of the three component parts of the optical “sandwich” that would make up the mirror blank went badly wrong: the 3,600-degree furnace fused the internal structure in a way that would probably cause it to crack during polishing, and so, for three months, Corning workers had to slice out the fused portions with acid and dental tools.
Never before had Corning made so challenging a piece of glass. Never before had Perkin-Elmer been given so demanding a remit: the NASA contract required the firm to grind and polish the finished fused-quartz glass piece, taking away at least two hundred pounds of material in doing so, and shape the immense tablet into precise convexity, with a surface of a smoothness never achieved or desired before. No part was to deviate by more than one-millionth of an inch. The satin-smooth surface was to be such that if the mirror were the size of the Atlantic Ocean, no point on it would be higher than three or four inches above sea level. If it were the size of the United States, no hills or valleys on its surface would deviate by more than two and a half inches from plane.
The crude grinding of the glass slab began at the Perkin-Elmer plant in Wilton, Connecticut, just as soon as Corning delivered it, yet all manner of delays plagued even this period in the mirror’s history—especially the so-called teacup affair, when a teacup-size web of internal cracks and fissures was found deep inside the glass, and had to be cut out and reamed and remelted, in a process akin to brain surgery. Finally, in May 1980, already nine months late, but with the mirror’s basic shape achieved, the great glass object was carefully trucked to the hitherto secret facility outside Danbury, and the serious polishing began.
The piece was carefully lowered onto a fakir’s bed of 134 titanium nails, a crude simulation of the gravity-free environment in which Hubble would eventually operate, and a computer-directed swiveling arm was moved into place over the piece. A spinning cloth pad at the arm’s end, smeared with a variety of progressively less and less abrasive substances (from diamond slurry to jeweler’s rouge to cerium oxide), was then lowered onto the face of the glass plate. Under computer control, it steadily stripped away and purged and polished and smoothed the surface, with polishing runs lasting for as long as three days, day and night. Polishers often worked back-to-back ten-hour shifts. Three days of polishing would be followed by a move to the testing room. Then, based on what the testers measured, new computer instructions would be issued, to polish this segment at this pressure and with this abrasive powder for so many hours and to then polish that section at quite another pressure and with a wholly different abrasive for more or less a similar period of time. That run would be finished three days on, and new tests would be ordered, and so the routine would continue, week after week after week. Testing was usually done at night, so as to minimize vibration from the daytime cavalcades of trucks passing by on Route 7; managers switched off air conditioners, too, for the same reason. Companywide, all were most scrupulous, firmly believing in their reputation for paying attention to the most minute of details.
The Hubble telescope’s eight-foot-diameter primary mirror being polished at the Perkin-Elmer Corporation’s top-secret facility in Danbury, Connecticut. An overlooked measurement error on the mirror amounting to one-fiftieth the thickness of a human hair managed to render most of the images beamed down from Hubble fuzzy and almost wholly useless.
Yet, once in a while, they made trivial mistakes, or rather, they wrongly instructed machines, which then made their own trivial mistakes, as ordered and on demand. Gone were the days when a skilled mirror maker could make certain of the precision of a surface by running a practiced thumb along it. Now such measuring was all done by machines, and one day, a Danbury engineer punched the number 1.0 into a terminal instead of 0.1—and watched in horror as the abrasive tool started to gouge a trench in the side of the glass. Mercifully there was a check technician standing by holding a Kill switch. He noticed the incipient gouge and stopped the polishing dead in its tracks. The small nick in the glass never fully went away, but it was smoothed over to a degree and left as a reminder, one that properly informed astronomers could work around.
It was in the testing room that the fatal error was made, and it was not a trivial one. For, while the smoothness or surface precision of the mirror face was being created with unforgiving certainty, the measurement of it was entirely and utterly wrong. The Danbury crew had made their measuring tool incorrectly: they were using an instrument that was rather like a straightedge that was stated to be, and was thought by everyone who used it to be, exactly one foot long, but that in fact measured thirteen inches—and nobody ever noticed. This was unknown to the engineers—they were busily measuring and then manufacturing something that was perfect but entirely wrong. They were making a telescope mirror that would be precisely imprecise.
The tool they made to measure the glass was a familiar piece of equipment called a null corrector. It was a metal cylinder about the size of a beer keg, and it held a pair of mirrors and a lens. Laser light was bounced against the two mirrors, then through the lens, where it would be directed to and bounced off the polished surface of the mirror before being passed back to the corrector’s lens and mirrors once again, and to the point where the light originated. If the polishing was perfect, then the light going out and the light coming back would match, wavelength for wavelength, and would produce in a photograph a pattern of straight and parallel lines. If the mirror was not the desired shape and smoothness, then the waves would interfere with one another, and the photograph would display an interference pattern. The null corrector, a million-dollar specially built measuring device, was in essence an interferometer, a device that, if properly set up, would be capable of confirming the absolute precision of the mirror surface, and to a fraction of the wavelength of light.
A worn patch of paint and three tiny washers turned out to be the culprits that led to a so-called null corrector giving a false result to the shape of the Hubble’s main mirror.
It could, that is, if—and this was a crucial if—the distance between the lower of the two mirrors inside the null corrector and the lens at its base was known with precisely measured exactitude.
And in the case of the Danbury corrector, it wasn’t. And it wasn’t for two of the plainly silliest and most prosaic and imprecise reasons imaginable.
To set the distance between the null corrector’s lower mirror and the lens required the making of a metal rod of the exact length required—and so three such rods (two as spares), made of the less-heat-sensitive alloy Invar, were made, measured, and cut. One of these metering rods was then fitted inside the null corrector and a laser trained onto its tip. Using a specially made microscope, a technician then worked with a laser interferometer to set the distance that the lens was to be adjusted to, so it would end up in the right place. It was a tricky job, but not an impossible one—and to make it easier for the worker, a special guide cap had been fitted to the very top of the metering rod with a minute laser-beam-size hole cut in it, indicating the place where the laser should be aimed, to ensure the technician hit the rod’s very tip.
Crucially, fatally, the cap had been covered with a non-laser-reflective coating, to make quite certain the laser would focus not on the cap but on the metal tip that was visible through the hole alone. It turned out, though, that a small portion of the coating on the cap had worn off, and the laser focused on, and was reflected by, that part of the cap, instead of traveling on through the hole to the rod’s metal and similarly reflective tip. The cap’s surface was exactly 1.3 mm higher than the tip of the rod, so the laser interferometer calculated the distance incorrectly by that exact amount.
The difference then made it mechanically impossible for the technicians to set the lens where the laser had said it should be set. The bracket holding the lens was out by 1.3 mm. Something was needed to bring this bracket down by 1.3 mm. There was no time to custom-make a new bracket.
So, resourceful as technicians often have to be, they made a decision. They would put three household washers into the null corrector to force the tiny lens 1.3 mm lower. They had to do this because the laser could not possibly be wrong. Lasers are so precise they never lie. They tell the absolute truth, with cold-eyed reliability. So three washers, flattened with hammers such that together they would form a tiny sandwich 1.3 mm high, were placed above the lens, which then and at last assumed the position that had been ordered.
After which, handling with extreme, crown jewel–like care the now completed but, as it happened, now profoundly flawed null corrector, the technicians slid it into position above the telescope mirror. Employing its electronic infallibility, the engineers measured and measured again, and eventually proved to their own satisfaction that in size and shape and configuration the Hubble Space Telescope’s primary mirror was exactly, precisely, as ordered by NASA.
Yet it wasn’t. It looked good according to the null corrector, but the null corrector was wrong. The NASA inquiry was able to demonstrate this because the Perkin-Elmer mirror makers had left it in the testing room, and had left the testing room exactly as it had been when they made their final measurements on the completed mirror, nearly a decade before.* The result was that at the edges of the mirror the tiny error in the metering rod, and thus in the null corrector, had produced a change in the measurement of the primary mirror’s shape that amounted to a 2.2-micron flattening around its edges—the famous one-fiftieth-of-the-thickness-of-a-human-hair deviation from design. A literally microscopic error, but one that resulted in the wholesale uselessness of the images sent down from space early in that summer of 1990, and which rendered the Hubble a laughingstock.
“If you had polled all the engineers and scientists at the Cape the night before launch for the top ten concerns they had,” remarked Ed Weiler some while later, “what could break on Hubble or what wouldn’t work on Hubble, I would bet my house and a lot more that not one of them would put on their list [that] the mirror is the wrong shape and so we have now got spherical aberration. Nobody worried about that, because we were assured by the optics guys that we had the most perfect mirror ever ground by humans on Earth.”
As indeed they had, but they also had an inaccurate measuring device that told everyone the mirror was perfect, and by its own standards, so it was. But its standards were disastrously imperfect, inaccurate, and wrong.
“FOR WANT OF a nail . . .” goes the ancient proverb.* In this case, it was the simple want of a patch of paint on an Invar rod, coupled with a degree of insouciant carelessness among a group of harried technicians and their budget-strapped managers, that led not to the loss of a kingdom, of course, but to a cascade of events and risky ventures and the expenditure of yet more taxpayer money in order to make repairs.
For Hubble was in due course repaired, and made good. It has become so successful, in fact, that it is repeatedly cited as the most valuable scientific instrument ever made, allowing for exploration of the outer regions of the universe to a degree that astronomers had never dreamed possible. It did have its error reversed, and its defects repaired, and so well—yet this came about every bit as improbably as the making of the error in the first place.
The repair had to be performed out in space—there was no chance of bringing Hubble back down into the shop. The installation of corrective optics should have solved the main problem—it would have been rather like giving a severely myopic person a set of contact lenses, or a form of Lasik surgery—yet, for a variety of technicalities, such a repair was going to be very difficult. The telescope tube was narrow and filled with a mess of instruments, pipes, and wires, and to send an astronaut swimming down into it with an oxygen pack and a wrench and a screwdriver and holding a new set of optical correctives was going to be exceptionally difficult, for a host of reasons.
Then one man solved this central problem, and he did so in a sudden moment of lateral thinking that came to him while he stood, stark naked, in a shower in a hotel bathroom in Munich, in the mountains in the south of Germany.
His name was Jim Crocker. He was, at the time, a senior Hubble optical engineer, and he was quite as devastated as the rest of the crew. Like most who had gathered in Germany for a crisis meeting of the European Space Agency, where everyone was imploring everyone else for a solution to the floating problems of Hubble, Crocker was obsessed with the need to make repairs. All that was needed was a means of inserting corrective optics, lenses or mirrors of one kind or another, into the stricken device. It would not be possible to put them in front of the primary mirror, between it and the secondary reflector, as not even the slenderest astronaut known to NASA could slither into and out of the main tube. No, the only place to site the corrective devices—and there would have to be four of them: one for each of the detectors carried on Hubble—would be behind the mirror, in the detector space itself. But how to get them to deploy? That seemed the impossible bit.
Jim Crocker, a NASA optical engineer, was taking a shower in his hotel in Germany when he realized that a device basically similar to a German shower mount could be used to probe inside the Hubble telescope tube and repair the optics or install corrective ones. NASA agreed and sent up the necessary device, which resulted in the total instant repair of the stricken telescope.
Photograph courtesy of NG Images.
Then Jim Crocker took his shower, and mused, as one does under a stream of hot water, looking idly at the shiny chrome-plated components of a typical German shower, and did a double take. He then looked more carefully.
The showerhead was held on a vertical inch-thick rod, on which traveled a clamp that held the head, which itself could be raised and lowered and locked in place to accommodate hotel guests of differing heights and preferences. Moreover, the showerhead that traveled up and down along with the clamp could itself be angled up and down and from side to side, depending on whether the occupant of the shower wanted to bathe his head or shoulders or wherever. The hotel maid had left the showerhead at the base of the rod, and had left it folded up, so that it was parallel to the wall. In order to use it, Crocker had to slide it up to his head height and then fold the showerhead outward to direct the water to his hair.
Why not, mused our drenched and ever-more-cleansed engineer shower taker, mount the telescope’s corrective optics onto a rod like this? Why not have them folded flat as they were slid into position, to be extended automatically into their preplanned and precisely determined base locations, then unfolded, just like the showerhead, into the correct angles and exactly calculated places?
There would need to be five of them—five “showerheads” instead of one, each to service one of the five main instrument packages the Hubble carried. Making five would, in truth, be no more difficult than making one. Each would have the same function: it would intercept the beams of starlight that had been reflected from the secondary mirror and that passed back through the center hole of the ruined primary mirror. They would then act on these beams and, much like contact lenses or corrective glasses, would refigure, recompute, and refocus them so that when they passed into the various Hubble detectors, they would be as perfect and as sharp as if the misshapen mirror’s misshapenness had never existed.
It seemed so simple a plan, and the engineers working on the fix jumped on it in an instant. All promptly set to work on creating a showerhead apparatus of their own, but one that would carry an array of tiny (dime- or quarter-size) mirrors into space instead of the customary shower of warm water.
As, indeed, they did. The device was to be named COSTAR, or the Corrective Optics Space Telescope Axial Replacement—“axial” because the part was to sit behind the primary mirror and work with the light that traveled along the axis of the telescope. Very basically, it was a telephone box–size container made to exactly the same specifications as one of the instruments already aboard Hubble, the least important of the four axial detectors, known as the High Speed Photometer, and which would now be sacrificed (to understandable howls of protest from its manager) to accommodate the box with the new foldout mirrors.
Engineers swarmed in to hand-make the COSTAR, and to make it exactly right—the ten mirrors (which, in the end, did not swivel out, as in Crocker’s showerhead, but sat atop an extendable tower and then radiated out from it, horizontally) having to achieve positions correct to at least one-millionth of a meter in order to be able to intercept the rays from Hubble’s two existing (and shamed) main mirrors.
One critical problem was how to make certain the beams of reflected light destined for the axial instruments missed quite another cluster of beams that were destined for the one instrument that was set not into the end of the Hubble but into one side of it, and which was itself being totally replaced for its own mirror-related problems. This was the immensely costly Wide Field and Planetary Camera, which was built at the Jet Propulsion Laboratory in Pasadena. It looked like a large slice of cake (though the size of a grand piano) and was slotted into the curved side of the Hubble. The astronomers had always reckoned on replacing this device with a new and improved one during one of the five planned shuttle servicing missions. Now, with the first such mission due, they could do two crucial things at once: replace the High Speed Photometer with the COSTAR package and also install the replacement Wiffpic, as JPL’s Wide Field Camera was affectionately known, and which had corrective optics of its own built in, to compensate for the errors in the primary mirror.
All that remained to bring the saga to a satisfactory conclusion was for astronauts to go up into space to make the necessary repairs. Hubble should then have been totally fixed and should have ended up every bit as valuable a piece of astronomical equipment as had first been promised—which would happen if the servicing mission worked as it was designed to, and in particular, as long as no one during the servicing dared to touch, even lightly, the little mirrors on either the COSTAR or the replacement Wiffpic, as touching them would take the repaired Hubble right out of focus yet again.
It was Endeavour* that was chosen for the critical voyage, for what was designated by the shuttle teams as STS-61 and by the Hubble teams as HSM-1, the first Hubble Service Mission. She was launched in the heat of the Florida night just before dawn on December 2, 1993, with plans and equipment (including some two hundred specially made tools) destined to bring to an end the forty-four-month nightmare of this half-blind and shuddering telescope that was relentlessly orbiting near-uselessly around the globe. The Wiffpic and the COSTAR were in the cargo bay; spacewalks of exhausting duration were planned to make the necessary fixes; the incoming astronauts who were certified to venture outside knew there were thirty-one foot restraints and two hundred feet of handrails already built onto the Hubble, and they had brought their own as well, together with numberless tethering lines, to make sure that no one and no equipment would be lost to float away into the eternal nothingness.
The crew, using powerful binoculars, spotted the telescope on the third day of their mission. They then closed in on it with infinite slow care, extended the Canadian robotic arm when they were sixty feet away, grabbed the thirteen-ton (but out there, feather-light) device, and hauled it gingerly into the shuttle’s cavernous cargo bay. The crew of seven then began a series of walks in space (extravehicular activities, as NASA still unimaginatively calls such things) to perform the various tasks they had been assigned. Walk One (EVA One, more accurately) involved replacing the three (of six) gyroscopes that had gone awry, but it also served to allow the team to get accustomed to the size and scale of the patient on which they were working. (They had been training for eleven months, performing all these various tasks underwater, to simulate somewhat the lack of gravitational pull in space.)
Walk Two had two of the astronauts repair and replace the telescope’s damaged solar arrays, which were said to have been causing the shuddering of the Hubble—a rapid movement that hardly helped the out-of-focus situation, yet paled in insignificance by comparison with the central problem. Matters started to get really interesting the next day, when the team began the tricky maneuver of removing the old Wiffpic and replacing it with the new version, which had its phenomenally delicate and precisely sited mirror spiking out of its very tip. Nothing untoward happened, either to it or to the camera, and the whole assembly slid into place with well-oiled ultraprecision, every part of it linking tightly with the bends and turns of the cavity inside which its predecessor had been living for the previous four years.
Nor was there any major problem with the culminating moment of the mission: the removal of the enormous High Speed Photometer and its replacement by the identically sized but wholly differently purposed COSTAR mechanism. Perkin-Elmer, shamed by its incompetence, had had no hand in the construction of this new mess of corrective optic mirrors. An entirely new company, called Ball Aerospace (descended from the company famous for making jam-preserving jars), out of Colorado, had won the loyalty and trust of NASA and been awarded the contract instead. And Ball had done well, with all measurements good, all fits exemplary, all tolerances met and matched. It took less than an hour to install the new optics package—it was almost anticlimactic, so flawlessly did it take place—before the crew members spent a final day tidying up and making cosmetic adjustments to their handiwork before leaving Hubble ready for business once again.
As a final dealing with Hubble, they opened its aperture door (the garbage bin lid, as it were), at the front of the telescope, and then attached their robotic arm to the monster spacecraft, lifted it very carefully out of the Endeavour cargo hold, and placed it gently beside (but now outside) their hull. Then, and as Captain Cook’s crew would have said, they cast off springs and released the lashings that bound telescope and orbiter together. Finally—but this time as Cook’s crew could not ever have imagined—they fired their thruster motors for a brief orbit-killing moment and headed back down to land.
Now Hubble, traveling still at seventeen thousand miles per hour, but with its orbit very slightly and deliberately enhanced, reverted to its lonesome and unattended state, on its near-endless silver journey around the globe.
Had the repairs gone well? Was Hubble going to work? Was the humiliation over, and could the true value of this extraordinary device be seen, at last, for what it had always been intended to be?
All eyes now turned back to the control rooms, at the Mission Operations Center at Goddard, where they would resume flying the telescope; and more crucially, at the Science Operations Center at the Space Telescope Science Institute at Johns Hopkins, in Baltimore, where the astronomers would download and then translate the new images, and would immediately know their fate.
The long-ago inaugural glimpse from the space telescope, the basic concept for which had been advanced as long ago as the 1940s, had been termed First Light. The Great Disappointment, they might have termed it instead, the moment Eric Chaisson, also in Baltimore, examined the initial images and felt, as he later put it, that infamous total deflation in his gut.
Now this was December 18, 1993, some thirteen hundred days later. Back in 1990, First Light had been summertime. Now, for what was being called Second Light, it was winter nighttime. It was dark in Baltimore, it was silent, and it was cold. At the Science Operations Center, an astronomer ordered the tiny onboard electric motors to spin out the corrective mirrors inside COSTAR and set them into their precisely allocated positions, to begin reordering the light beams inside Hubble. They also opened the shutter on Wiffpic, which had its own cleverly arranged optical correctors, buried deep within itself. Goddard obligingly pointed the enormous telescope toward a possibly fruitful portion of the sky. Everyone waited as the images slowly started to unscroll from the top to the bottom of their monitors.
Ed Weiler was there, the NASA engineer who had taken that first grim telephone call. Like everyone else in the room, he had his eyes locked on the screen. The next three seconds were the longest three seconds, Weiler said later, he had ever experienced in his life.
There was a sudden explosion of exuberance, applause, delight, and joy. The image on the screen was now complete, and it showed before everyone a vivid mass of stars, all in focus, with one star in the dead center occupying just a single pixel of the screen. One star, one pixel.
The image was sharp, perfectly, precisely sharp. No more fuzziness. No marshmallow. No soft edge. All was exact, aligned, impeccable, just as hoped for back when the project was a mere notion in a group of astronomers’ heads. No other optical telescope that had ever been made and established on planet Earth (even those at the summits of great mountains in Hawaii, in Chile, on the Canary Islands, and in other places where the air was at its thinnest and clearest) could ever rival this.
Because down there was air—even when thin, it was heavy, windy, polluted, dancing with molecules, potent with distortion. Yet up here, nearly four hundred miles up, high above the troposphere, the stratosphere, the mesosphere, in what is now called the exosphere, where there was just the occasional hydrogen molecule drifting through, there was no air, and no distortion—and where now, at last, and thanks to the cleverness and cost of a whole set of new optics, humankind had a clear-eyed new viewing platform, like no other ever before, from which to observe.
Half a century after it was first conceived, twenty years after it was first designed, fourteen years after a computer in Danbury told the first polishing arm to travel across the great tablet of Corning quartz and begin to grind and shape its surface, and thirteen hundred and some days after that overflattened eight-foot mirror took its first long gulp of light from the universe wrapped around it, a repaired telescope with new precision optics was able to see clearly deep into the distance, and into the distant past of the cosmos.
The rest of the Hubble story is still being told today. Four further servicing missions have been up to it, as were scheduled long ago, each one tasked with breathing new life into what has become a beloved old silver workhorse, the greatest of NASA’s great observatories. The longevity of the now almost venerable, if still no prettier, bird is greater than ever anticipated, and it is now expected to continue flying at least until 2030, maybe for a decade longer. It is by all accounts the most successful scientific experiment of modern times, maybe even of all times. And the images it has sent back, tens of thousands of them, have captivated all who see them. The eight-foot mirror, imperfect though it may be, has captured a vision of wonder and rapture to scientists and the lay alike, bringing the universe vividly to life.