Yale University Press, 1936
American civilization’s claim to greatness turns on many achievements. Not least among them has been its leadership in the natural sciences. Of the American sciences, astronomy has been second to none in the national diadem, and no astronomer’s name is better known today than that of Edwin Powell Hubble. Everyone of course knows of about the instrument that carries his name today, the Hubble Space Telescope, but too few know about the man himself, or that, before Hubble could work a revolution in astronomy, he first had to work one in his own life. His father, you see, was dead set on young Edwin’s becoming a lawyer.September 7, 1910, found Edwin Powell Hubble on a train steaming northeast from Chicago to Montreal, where he was about to join his fellow Rhodes Scholars on the passenger ship Canada for a voyage across the Atlantic. One of Hubble’s new acquaintances snapped his picture as he stood, feet firmly planted on the rolling deck, “towering”, to borrow Dr. Samuel Johnson’s words, “in the confidence of twenty-one.” His large hands are thrust nonchalantly into the pants pockets of his new three-piece suit, accented by a heavy cardigan, stylish bow tie and tweed hat. While he had never before set eyes on an ocean, he seemed like a man for whom sailing off across the Atlantic to the Old World was routine.Though Edwin, about to reach his majority, had never given his parents serious cause for concern, his puritanical father, a dyed-in-the-wool Baptist and strict disciplinarian hailing from Missouri, fretted nonetheless. The world was full of snares and pitfalls, John Powell Hubble repeatedly cautioned his second son, not least among them the siren songs of loose women. With his parental control slipping away, John secured a promise from Edwin that would prove impossible to keep: The young man pledged not to imbibe so much as a single drop of liquor, which presumably included any that might make their way into French cooking.His father exerted influence in other ways, as well. The day after Hubble received word that he had bested the only other Rhodes finalist from Illinois, a University of Chicago campus reporter asked the student about his plans for studying abroad. “Too soon to say for certain”, he replied, given the fact that he didn’t yet know which of Oxford’s colleges he would be attending. He noted that he had mostly studied physics and other sciences as an undergraduate, but “I expect to take up law and international law at Oxford. Most excellent courses in both these subjects are offered in the English institution.”1 What young Edwin did not tell the reporter was that this decision had been made for him by his father, well before Edwin received a scholarship. His younger sister Betsy may have remembered how the youth had “only one thought in his mind—astronomy—and he wasn’t going to let anyone else bother that.” But another sister, Helen, saw their father’s will at work: “Papa wouldn’t have let him go through school if he was going to be a thing so outlandish.”2An insurance agent by calling, John was fond of pointing out that one decent-sized classroom could hold every astronomer in the United States and Europe combined. The law, on the other hand, abounded in possibilities both economic and political, and Edwin could do no better than to hang out his shingle in the Hubbles’ native Missouri, where their name was well respected. Father and son had agreed to a deal at university whereby Edwin could take the courses in mathematics and science leading to the advanced study of astronomy, so long as he also fulfilled the prerequisites for admission to law school. But once Edwin graduated and became a Rhodes Scholar, father John’s sway re-emerged.When Hubble arrived at Oxford’s Queen’s College, he was assigned second-floor rooms on the inner triangle next to the library. The University of Chicago’s architectural attempt to evoke history through the Oxford model had suddenly given way to history itself. The stone corridors Hubble walked echoed the footfalls of Joseph Addison, Jeremy Bentham, Walter Pater and, in an ironic twist, the astronomer Edmond Halley, whose namesake comet was fast closing on the sun on its 76-year circuit through space. Defying the prognostications of local fatalists, the Hubbles had passed the summer nights watching as the streaking visitor rent the firmament like a gigantic sword.Hubble took to the patrician life as if to the manor born. He was oblivious to the fact that many thought him a “phony Englishman”, from his baggy plus-fours and Norfolk jacket to a trailing black cape and walking stick. What is more, his first letter home suggests a remarkabl y rapid transformation when it came to the king’s English. Within days of his arrival, Hubble was speaking and writing the affected upper-crust jargon that gradually died out in the 1920s and 1930s. One did not talk the hours away, one “jawed” them. One had a “ripping good time” with friends, who were “splendid fellows” and “mighty good sorts.” One such friend was Jakob Larsen of Iowa, who was studying classics at Queen’s and thus had a close-in view of Hubble’s metamorphosis: “We laughed at his effort to acquire an extreme English pronunciation while the rest of us tried to keep the pronunciation we brought from home.” So alien had her son’s prose suddenly become that one can almost picture mother Virginia double-checking the handwriting to make certain it was truly Edwin’s.It was Larsen who recalled that Hubble was, from the very beginning, little interested in jurisprudence but “full of astronomy.” Unbeknown to John, his son had become a familiar face at Radcliffe Observatory, one of Oxford’s most beautiful structures. It was there that he met Professor Herbert Turner Hall, a leading figure in celestial photography. Daisy Turner later wrote that she and her husband were charmed by Hubble’s colloquial mannerisms when he came to dinner, a vestige of his Missouri upbringing and an additional reason for affecting the English tongue.Daisy remembered a friend remarking about Hubble, “You said you had asked a Queen’s undergraduate to dinner, but you never said he was an Adonis.” Standing above six feet tall and weighing 190 pounds, Hubble took full advantage of his commanding physique. When a certain captain got into an argument with a Moravian count over which of them was to have the next dance with a future duchess of England, Hubble supposedly stepped between the two and spirited the bone of contention away like Sir Walter Scott’s young Lochinvar. He wrote his mother that it was all great fun; “it always is to look a man in the eyes and best him by sheer self-possession.” He had succeeded at last in gaining access to England’s elite, otherwise referred to as “the bloods.” He had begun smoking a pipe, too, and had developed a fondness for the hearty ale brewed at Queen’s, not to mention a budding connoisseur’s taste for European wines. Edwin’s foppery had not set well with the Warden of Queen’s, and was reflected in his final assessment of the young American: “Considerable ability. Manly. Did quite well here. I didn’t care very much for his manner—but he was better than his manner. Will get A.”Hubble’s dream within a dream was rudely interrupted when his father suddenly fell ill. As John lay dying cables crisscrossed the Atlantic. Edwin promised to return home as soon as possible; John replied that Edwin must remain at Oxford, for the family might never find funds for him to return to complete his third and final year of studies. And so John died of Bright’s Disease at age 52 in January 1913.When Edwin finally did return home to his family, then removed to Lexington, Kentucky, it was to a houseful of virtual strangers, including a wide-eyed Betsy, who was shocked by her big brother’s antiquated dress. “He had on knickers”, she recalled, “and men didn’t wear knickers then.” He brought along the rest of his Oxford props as well, including cape, walking stick and contrived accent. Once home, it was Edwin, rather than his older brother Henry, who sat at the head of the dinner table and instructed Virginia on the finer points of brewing a proper cup of tea.Hubble claimed he had passed the Kentucky bar examination and had racked up the then-princely sum of $10,000 in legal fees. Neither of these assertions could have been further from the truth. Instead, he taught high school mathematics and Spanish at New Albany, Indiana, just across the Ohio River, where the female students went “gaga” over their handsome new teacher. After a year of this charade, Hubble accepted a meager graduate tuition scholarship at the University of Chicago to study astronomy. The university’s magnificent Yerkes Observatory, opened in 1897, sat on the banks of Wisconsin’s Lake Geneva, a pristine body of water a mile wide and eight miles long. Here was located the Holy Grail of modern Victorian astronomy: a gigantic forty-inch refracting telescope, its sixty-foot-long, six-ton steel tube pointing skyward like a massive cannon. Dwarfed as the Lilliputian observer is by the 140-ton dome, one’s attention was soon drawn to the observing room floor—75 feet in diameter and weighing 38 tons—which rose like an opera set at the press of a button, depositing the awed astronomer at the foot of heaven’s gate. Hubble took his turn at the mighty instrument, but mostly the neophyte was relegated to an almost forgotten 24-inch reflector. Ironically, this was the very piece of equipment he needed to pursue his photographic reconnaissance of faint nebulae, those whiffs of stars or gas or other mysterious matter that would one day provide him with the key to the size of the universe itself.In the meantime, a 100-inch reflecting telescope, at that time the world’s most revolutionary observational instrument by far, was nearing completion atop Mount Wilson Observatory, outside Pasadena. While on a scouting expedition to secure new talent for the enterprise, Mount Wilson’s assistant director met up with a Chicago graduate student named “Hubbell”, who seemed an excellent prospect for one of the five positions about to be filled. A short time later, Mount Wilson’s director, George Ellery Hale, the peripatetic dean of American astronomers, offered Hubble the position of assistant astronomer at a salary of $1,200 per year, once his dissertation was completed. Hubble agreed enthusiastically. Then the world itself promptly fell apart.The entry of the United States into World War I brought a halt to most studies astronomical. Hubble himself was itching to get into the fray, and pushed as hard as he dared to convince his dissertation committee that he should be allowed to finish the work before enlisting in the army. Despite certain reservations on both technical and theoretical grounds, the committee approved the brief study. While only a scant seventeen pages in length, “Photographic Investigations of Faint Nebulae” was prophetic of the Magellanic voyage ahead. Hubble was convinced that at least some of the great but diffuse nebulosities, connected as they are to stars visible to the naked eye, lie within our stellar system. Yet beyond them, Hubble also was convinced, are ill-defined classes of seemingly numberless faint nebulae, revealing themselves as nothing more than porridge-like markings on the photographic plates. “Suppose them to be extra-sidereal and perhaps we see clusters of galaxies; suppose them within our system, their nature becomes a mystery.” The answers to such cosmic riddles must await an “instrument more powerful than [any] we now possess.”3Shortly after enlisting in the Army, a hubristic Hubble wrote to a fellow Rhodes Scholar that these are “stirring times—I can’t picture myself missing the gathering, as it were, of the clans.” But with the tedious counting of the days and unchanging orders to stay put, the Great War turned into the great disappointment of Hubble’s life, despite the fact that he had risen to the rank of major and was well respected among his fellow officers. After 14 months of marching across the barren cornfields of northern Illinois, Hubble’s division had just made it to Europe when the guns of August fell silent. “I am disappointed in the matter of the war”, he wrote Edwin Frost, his aging and nearly blind professor at Yerkes. The “big show”, he hated to admit, was over, and for the first and only time in his life Hubble got tight on a free-flowing local wine.Still, there remained the cachet of the uniform, the vicarious sense of the heroic associated with a great conquering force and a deeply indebted populace, a lingering camaraderie among those who had put their lives on the line—or had been willing and had tried to do so. So Hubble decided to stay on in England and took rooms on Cambridge’s Eligius Street, living the real life of Fitzgerald’s enigmatic Jay Gatsby while processing reparations claims. But the great machines of modern astronomy pulled at him, and so it was that some five years later, in October 1923, Hubble found himself preparing for another chance at a photographic “run” atop 5,714-foot Mount Wilson.Hubble had returned to the United States in 1918. His new bride Grace, a petite brunette whose first husband had been killed accidentally while inspecting a coal mine for the State of California, always noted a marked change in Edwin whenever he had business on the mountain. At breakfast, it seemed to her that he was already gone, for he took no notice of the newspaper and picked at his bacon and eggs absentmindedly, a distant look in his hazel eyes. Waiting for Hubble at the wheel of the observatory’s Mack truck was driver Mike Brown. The astronomer dropped his bag in the back, and they lumbered out of the waking city.By now, Hubble was well acquainted with the behemoth awaiting his arrival, including its every hitch and idiosyncrasy, of which there were several. Named for a Los Angeles businessman enthralled by the stars, the reflecting mirror of the giant Hooker telescope had been cast in France, taking the shape of a 100-inch-wide glass disk. The monumental task of hand grinding 7,800 square inches of surface area had taken nearly five years to complete, the workmen fitted out in protective gear from head to toe. On its surface would eventually fall an estimated three billion points of light.The telescope’s sheet-metal dome—one hundred feet high, 95 feet in diameter, and 600 tons—didn’t so much rest as float on tanks of mercury, allowing the celestial battering ram to be moved with the touch of a hand. Dwarfed by an immensity of scale that some likened to the Great Pyramid, the lone astronomer sat suspended on the observer’s platform, which consisted of little more than a few square feet of wood flooring and a bentwood chair. The heavy clang of machinery and a rumbling that reminded the transplanted Missourian of gathering thunder echoed through the darkness as the 100-inch was clamped. Hubble sat back and deliberately filled his English briar with tobacco, then slid the cover from the first photographic plate and called out the exposure time to an invisible assistant at the console below. He then told the young man he could go and catch up on his sleep, for Hubble preferred to do the guiding on his own. He was sure of what he wanted to do and of exactly how to do it.After completing one of his runs, Hubble was about to undertake a more thorough examination of plate H335H, the initials standing for “Hubble” and “Hooker Telescope”, the number being the 335th taken by the astronomer on the 100-inch. An image of the Andromeda galaxy had caught his eye, for it appeared to contain a previously undetected nova, a variable star that suddenly increases in brightness thousands of times over. Additional research in the photographic archives would reveal what appeared to be two more such objects. Deeply satisfied at the prospect of fathering triplets, the weary astronomer had no idea that on the seat beside him, carefully swaddled to protect it from damage, was a glass image destined to change mankind’s understanding of the face of the universe forever.Hubble’s keen interest in Andromeda’s suspected novae was rooted in one of the supreme astronomical questions not only of the day, but of all time: Is the Milky Way the universe entire, or is it but one of uncountable stellar systems (galaxies) scattered throughout the void? Most astronomers in his day were dead certain that the Milky Way was an estimated 300,000 light-years across, a combination stellar nursery and graveyard encompassing every particle of matter in existence. Indeed, Harlan Shapely, Hubble’s predecessor at the Mount Wilson Observatory, where Hubble made his startling discoveries, was fond of referring to his cosmic brainchild as the “Big Galaxy.”By comparing all the relevant plates available to him, Hubble quickly determined that one of his three “novae” was subject to regular cycles that bore no resemblance to the behavior of similar stars. In plotting the object’s light curve, or distance from earth, he discovered it to be at least 300,000 parsecs away—the equivalent of a million light-years, or more than triple the diameter of Shapley’s entire universe. Andromeda’s spiral arm was bejeweled by a Cepheid variable, a pulsating supergiant star whose brightness varies in regular periods. The nebula thus could not be a part of the Milky Way but was instead a sister galaxy to it, both of them composed of teeming stars numbering in the billions.If ever there was a eureka moment in the science of astronomy, this was it. Yet for the time being, Hubble kept his own council, difficult though it must have been. All he did was cross out the letter “N” for nova that he had previously inscribed on the plate and printed “VAR!” (for “variable”) beneath it. And while the plate had been taken the previous night, he dated it “6-Oct. 1923” to commemorate the seminal moment when his mental tumblers had suddenly clicked.Still, he had to be absolutely certain before daring to let the cat out of the bag. A feverish ransacking of the heavens during the next four months yielded several more of the elusive variables. There could be no question that the universe was vaster than any poet of old had dreamed.It was time to contact Shapley at Harvard. Hubble wrote his fellow astronomer a letter dated February 19, 1924. “You will be interested to hear”, it began, “that I have found a Cepheid variable in the Andromeda Nebula.” Then the roof caved in. Hubble had photographed the galaxy throughout the winter months, his efforts rewarded by the discovery of an additional nine novae and two more Cepheids. The two men had never gotten along, and Hubble had no qualms about rubbing salt in the wound. “I have a feeling”, he crowed in his best imitation of Oxford prose, “that more variables will be found by careful examination of long exposures. Altogether next season should be a merry one and will be met with due form and ceremony.”As it happened, one of Shapley’s graduate students had been in his office when the letter arrived. The professor opened it and, after scanning its contents, passed it across his desk while issuing a cri de coeur that rings as poignant today as it did 75 years ago: “Here is the letter that has destroyed my universe.”
While Hubble was not above professional pride, he nevertheless took an impersonal and dispassionate approach in public when he discussed science. More than a decade later, while delivering the Silliman Foundation Lectures at Yale in what became The Realm of the Nebulae, Hubble’s little classic on astrophysics, he said:The solution of the problem [of distance] was an achievement of great telescopes. As telescopes and technique improved, they eventually reached a certain critical point and, in due course, the barrier fell. When the breach was open, a wave of exploration swept forward.4
Indeed it did, and much of that exploration Hubble himself led, up to the day of his sudden death in September 1953. He classified and systematized the observation of heavenly objects, developing a still-used diagram known as Hubble’s tuning fork. He improved the scientific instrumentation of astronomy. Above all, perhaps, building from his realization that the universe was expanding at a constant rate, he devised Hubble’s Constant—the ur-metric of the Big Bang.Hubble achieved through observation and deduction what others were striving to understand through theory and induction. In late 1930 Albert Einstein visited Cal Tech and Mount Wilson Observatory, where he admitted to having blundered badly in formulating one of his most important equations. He had followed the lead of other European physicists by postulating that we inhabit a static as against a dynamic universe, until Hubble’s revolutionary foray into the speeding galaxies convinced him otherwise.Of course, Einstein told Hubble this. The two spoke of science. But Einstein’s gratitude to the Missourian characteristically defied conventional boundaries. One day, as Grace Hubble drove Einstein to an appointment, the grizzled gnome leaned close and remarked to her in a near whisper, “Your husband’s work is beautiful.” And so it was.
1The Daily Maroon, January 27, 1910.
2These and subsequent quotes about Hubble’s life are taken from in Gale E. Christianson, Edwin Hubble: Mariner of the Nebulae (Farrar, Straus & Giroux, 1995).
3Edwin Powell Hubble, “Photographic Investigations of Faint Nebulae”, Publications of the Yerkes Observatory, Vol. 4, Part 2 (1920), p. 69.
4Hubble, The Realm of the Nebulae (Yale University Press, 1936), p. 83.