The Day We Found the Universe

by Marcia Bartusiak

  Soon van Maanen was running out of spiral nebulae to measure, as few had been regularly photographed for comparison over the years. As a double check on his dexterity with the Blink, he measured a simple globular star cluster, M13, which was known not to rotate. If there were any instrumental error, he should have mistakenly measured a motion, but he didn't, which seemed to imply his methods were valid. A British astronomer independently checked his methods as well and concluded that no one “would be so bold as to question the authenticity of the internal motions…. In fact, the more one studies [van Maanen's] measures, the greater is the admiration which they evoke.”

  Adriaan van Maanen's markings on a photo of M33 indicating the

  rotation he measured (From Astrophysical Journal 57 [1923]:

  264-78, Plate XIX, courtesy of the American Astronomical Society)

  “I finished…my measures of M51,” van Maanen wrote Shapley in the spring of 1921. “The results look more convincing than M101… Motion outwards along the spirals + some motion away from the center…. By this time Curtis and [Swedish astronomer Knut] Lundmark must be the only strong? defenders of the island-universe theory.”

  “Congratulations on the nebulous results!” responded Shapley. “Between us we have put a crimp in the island universes, it seems,—you by bringing the spirals in and I by pushing the Galaxy out. We are indeed clever, we are.” Shapley reported on his friend's latest results at that summer's American Astronomical Society meeting in Connecticut. “I think that your nebular motions are taken seriously now,” he told van Maanen afterward, “and nobody…dared raise his head after I explained how dead the island universes are if your measures are accepted.”

  The two were feeling quite cocky. At this stage, van Maanen at last made it publicly known, in the Proceedings of the National Academy of Sciences, that his observations “raise a strong objection to the ‘island-universe’ hypothesis.” If M33, the prominent spiral in the Triangulum constellation, for example, were several million light-years distant, he pointed out, the motions he detected would represent velocities near the speed of light, “which, obviously, are extremely improbable…[and] afford a most important argument against the view that these nebulae are systems comparable with our galaxy.”

  But this declaration was hardly a resolution to the Great Debate. While Shapley and van Maanen were smugly celebrating, Knut Lundmark was visiting the Lick Observatory, using the Crossley reflector to gather the extremely faint light of M33. It was a difficult task, requiring extremely long exposures, one totaling thirty hours collected over four nights. Lundmark eventually saw that the light from the nebula's spiral arms resembled nothing less than the light of ordinary stars. Where other astronomers had seen a fuzzy patch in a spiral arm and called it a “nebulous star,” Lundmark pondered whether each mistlike spot was instead “a great number of very distant stars…crowded together [to] give the impression of nebulous objects.” That led to his cogent conclusion: that his observations of the spiral arms “speak for a large distance.” The respected Swedish astronomer soon became one of the loudest voices championing the existence of other galaxies, and Shapley began to feel sizable pressure on his beloved model of the universe under Lundmark's onslaught.

  Meanwhile, Slipher, in Arizona, had dispatched a story to the New York Times revealing that he had found a new “celestial speed champion,” a faint spiral nebula that he judged had to be “enormously large” and “many millions of light years” away. And in the following year, 1922, Ernst Öpik, at the Dorpat Observatory, in Estonia, carried out an elegant calculation demonstrating how the Andromeda nebula must be some 1.5 million light-years distant. He did this by assuming that its mass and luminosity were comparable to those of the Milky Way. This “increases the probability,” reported Öpik in the Astrophysical Journal, “that [Andromeda] is a stellar universe, comparable with our Galaxy.” Thrust and parry. Thrust and parry. The duel over the island universes continued. Nothing would be settled until astronomers obtained a clear and unequivocal distance measurement to a spiral nebula—an observation so clear, so decisive, so comprehensive, that it immediately quelled all doubts.

  Poor Shapley, it turns out, did put himself in jeopardy with his performance before the National Academy of Sciences gathering. Still in his thirties, Shapley was judged as too impetuous and immature to be the head of the Harvard College Observatory. Instead, his Princeton mentor, Russell, was offered the position. “Shapley couldn't swing the thing alone,” Russell confided to Hale two months after the conference. “I am convinced of this after…observing Shapley at Washington. But he would make a bully second … if he grew intellectually he would be a prodigy!”

  Russell gave the Harvard directorship intense consideration, with the understanding that Shapley would be his assistant. “At this point,” continued Russell to Hale, “I would like to see your expression! I know I have my nerve with me: but,—and here I am very serious indeed,—consider what Shapley and I could do at Harvard! Between us, we cover the field of sidereal astrophysics pretty fully…and I might keep Shapley from too riotous an imagination,—in print.”

  But Russell, after nerve-racking deliberation and an attractive counteroffer from Princeton, ultimately declined the job (“I would rather do astronomy,” he confided to Shapley). Harvard came back to Shapley, but not for the top position. Harvard officials brought up the title of “Chief Observer or something of the sort.” He, a bit miffed, curtly turned it down. A month later, however, Shapley reversed his decision when Harvard (spurred by a suggestion from George Hale) agreed to try him out for a year as chief of staff, starting in the spring of 1921. He obviously passed muster, for he was soon named full director and served at the post for thirty more years, working at his unique desk that turned like a wheel—“a kind of rotating galaxy for ideas,” noted a friend.

  Shapley breathed new life into the sclerotic institution, bounding up the stairs two steps at a time and greeting everyone with a sporty cheerfulness. “He cast spells over people,” said one staff member. Pickering had run the observatory like an absolute monarch. Under the youthful and energetic Shapley, it became a band of enthusiastic workers. Leo Goldberg, a student at Harvard in the 1930s, compared him to a benevolent Mafia Godfather. On the one hand, “he inspired us all,” said Goldberg. “He pepped us up, he raised us out of the depths of discouragement many times.” But a darker side lurked within Shapley as well. Adopting a “divide and rule” principle, he could be a father figure to some, while a tyrant to others. He also stubbornly ignored new scientific data at times, if it conflicted with his personal vision of how the universe should work.

  Even as Shapley settled into Harvard, his former employer requested one more task from him. He was asked to contribute to Mount Wilson's annual report, to recount the final work he carried out there in 1920. “I thought I told you that I left Mount Wilson just to avoid this ordeal,” he replied playfully. “Suppose I had lived wickedly and unrepenting died—would you even then haggle with His Majestic Nibs for your annual tithe of Blood-and-Brain?” Shapley was again being Shapley. It was his last hurrah for the California observatory. Mount Wilson got its notes.

  Meanwhile, Curtis, who could have done much toward solving the mystery of the spiral nebulae, stepped out of the race entirely. Just a few months after the debate, he left the Lick Observatory to become director of the Allegheny Observatory, the same post that James Keeler once held. He had actually tendered his resignation ten days before the Washington debate took place. Being in charge of an observatory, a more highly paid position with increased prestige, was an opportunity hard to pass up, especially for a family man. But, as with Keeler, the urban setting, cloudy weather, and poorly equipped telescope at the Pennsylvania observatory ultimately prevented Curtis from making any further cutting-edge discoveries. Some considered it “the biggest mistake he ever made.” Even Curtis later confessed to his former boss Campbell that “the California combination of instruments PLUS climate is a hard one to beat…
There is no place like the hill [Mount Hamilton] for astronomical work and…any man who leaves these opportunities is bound to be sorry for it.” A visiting colleague found him at Allegheny one day puttering with an instrument and chided him for turning into a toolmaker. “You play golf don't you? Well, this is my golf,” he responded.

  Harlow Shapley at his wheel-like desk at the Harvard Observatory

  (Harvard College Observatory, courtesy of AIP Emilio Segrè

  Visual Archives)

  Despite their differences in cosmic outlooks, Curtis and Shapley remained cordial over the years and kept in touch through correspondence. More than two years after the debate, Curtis looked back on the event—what he called their “memorable set-to”—with good humor. “I have always thought that the clubs we wielded at each other were all the more effective because politely padded,” he told Shapley, “and regard with approbation the view-point of the old lady who warmed the water in which she drowned the kittens…. I fancy we both are as stiff-necked as ever; am sure that I am; cant [sic] see that my views have changed in the slightest.” With his new responsibilities at Allegheny, though, Curtis had to remain on the sidelines, resigned to simply “watching the strife with interest,” as he put it.

  A few years later, a friend from Lick asked Curtis what he would have done with the Crossley if he had stayed on Mount Hamilton in 1920. Curtis replied that he would have just kept “photographing, photographing, and yet more photographing.” He had in mind a “program of about 30 min. exposures of all the larger spirals at frequent intervals, to hunt for novae and variables.” In a nutshell, he would have done everything that Edwin Hubble later carried out at Mount Wilson using its 60-and 100-inch telescopes, but with a few years' head start. Was the Crossley up to the task? Curtis had total faith in his beloved telescope: “I am copying that instrument in my design far more than any other,” he said. “Could a ‘race’ be run between the 60″ and the Crossley, would bet on the Crossley every time.” Others, too, later judged the Crossley as having had a fighting chance at clinching the distance to Andromeda. But once Curtis left for Pennsylvania, no other Lick astronomer was interested in photographing the spiral nebulae. In effect, once Curtis left the Lick Observatory, it handed the baton over to Mount Wilson.

  Adonis

  From the mile-high summit of Mount Wilson, you can look a dozen miles to the southwest, across a wide valley, and catch sight of Hollywood and its lower-lying hills. The movie studios situated there in the 1920s were rapidly growing in allure and generating their mythic aura. This enchanted atmosphere must have somehow wafted over to the San Gabriel Mountains, for the man who eventually solved the mystery of the spiral nebulae looked as if he had come straight out of central casting.

  In the eyes of his friends Edwin Hubble was an “Adonis,” a tall and robust figure with compelling hazel eyes, a cleft chin, and wavy brown hair that glinted of reddish gold. Pronounced cheekbones cast attractive shadows in his photographs, lending his face a movie-star look. A woman screenwriter considered him too handsome for his occupation, comparing him to box-office idol Clark Gable. “Had we been casting [the role of a scientist] at M.G.M., Edwin Hubble would have been turned down as ‘unrealistic,’” said Anita Loos, author of Gentlemen Prefer Blondes.

  Raised in a solid middle-class household, Hubble somewhere along the line acquired a profound yearning to be singular and distinct. Fiercely determined to rise in the ranks, he reinvented himself upon reaching adulthood—adopting a British accent, dressing like a dandy, and adding dubious credentials to his curriculum vitae. The young man was seemingly intent on burying the most boring aspects of his midwestern family heritage and over time crafted a persona as big as the silver screen. By marrying into a wealthy southern California family, Hubble attained many of his lofty social and financial goals, and his wife, Grace, became his accomplice. She idolized her husband and, long after his death, propagated the legend he established, of which numerous details were highly edited or demonstrably wrong. She put him on a pedestal. And the longer time went on, said astronomer Nicholas Mayall, who had once worked with Hubble, the higher the pedestal got. Hubble's discovering the modern universe didn't seem to be glory enough.

  Born on November 20, 1889, in Marshfield, Missouri, Hubble was the third of seven surviving children and christened Edwin Powell, although he generally avoided using his middle name or initial. His father, John, who grew up in Missouri, was trained in the law but earned a living working in his family's insurance business. When not traveling, he ruled his domestic realm with a firm puritanical hand, a strictness that was balanced by the more forgiving and accessible mother, Virginia Lee (“Jennie”) James, daughter of a local physician.

  It was in Missouri, the “Show Me” state, that Hubble began his love affair with the heavens. His maternal grandfather, William James (a distant relation to the famous outlaw Jesse James), had built a telescope, and as a present on his eighth birthday young Edwin was permitted to stay up past his bedtime and use it to peruse the pinpoints of light, sparkling like brilliant gems, in the nighttime sky. The impression made on him that pitch-black winter evening, the starry wonders he beheld, lasted a lifetime. Two years later his family moved to the Chicago area, eventually settling in the village of Wheaton, Illinois, just west of the city. In high school Ed, as he was known to his friends, blossomed, regularly maintaining an A average and excelling in track, football, and basketball. The two areas in which he was downgraded a few times came in “application” and “deportment,” as he wasn't afraid to argue with his teachers in class. With his peers, he remained aloof and at times arrogant—both a dreamer and schemer. “He always seemed to be looking for an audience to which he could expound some theory or other,” recalled a childhood friend. Two years younger than most of his classmates, he may have been putting on a knowing front to appear older and more self-assured.

  Graduating in 1906 at the age of sixteen, Hubble was awarded a scholarship to the University of Chicago, partly due to his superb athletic skills. But what he would major in became a contentious issue. Never forgetting his childhood experience with his grandfather's telescope, Hubble earnestly desired to study astronomy, but his father, a practical man, wanted his son to take up the law. According to one of Hubble's sisters, John Hubble considered being an astronomer an “outlandish” career choice. Hubble compromised by taking science classes—mathematics, astronomy, physics, chemistry, geology—as well as the prerequisite courses in the classics, including heavy doses of Greek and Latin, that would prepare him for a legal career.

  In regard to learning science, the timing for Hubble was perfect. Though a relatively new institution, the University of Chicago had already attracted two top physicists, Albert Michelson and Robert Millikan, who would go on to receive Nobel Prizes for their seminal work. And the Yerkes Observatory, affiliated with the university, offered one of the best telescopes then in existence. The early 1900s was a time, Hubble later recalled, when the world was astir: “Motor cars, at last, were successfully competing with horses. Airplanes were trying their wings. Bleriot had just flown the English channel, and…the wireless was groping its way over the map. Marconi…transmitted a message from Ireland to Buenos Aires, 6000 miles away… Technology strides across the modern stage like some gigantic, streamlined god.”

  Edwin Hubble (left) in 1909 with a teammate on the

  University of Chicago track team (Reproduced by permission

  of the Huntington Library, San Marino, California)

  Hubble inhaled the charged air of this exhilarating era deeply. A classmate described him as being a “whiz” at calculus, who “often utterly dumfounded” the professor. By the end of his sophomore year he was singled out as the best physics student. He also participated in track (though seldom winning) but did better in basketball, as his exceptional height for the day (six feet two inches) gave him an advantage playing center. He and his teammates were national champions in 1909. Moreover, Hubble did some boxing at an off-campus g
ym, becoming so good as an amateur heavyweight that Chicago promoters were eager for him to turn professional (or so he claimed). Such diverse activities and coursework may have been all part of a plan, for early on he had set his sights on obtaining a Rhodes Scholarship. Cecil Rhodes, the British imperialist who made his fortune mining South African diamonds, had set up the program to strengthen the relationship between Great Britain and the United States. Every year, in each state, a young man was chosen to attend Oxford University in England for postgraduate studies. In his will Rhodes stipulated that Rhodes scholars should be bachelors between nineteen and twenty-five, good in academics but not “mere bookworms.” Each was to be a manly chap, exhibiting a “moral force of character” and proficient in both athletics and leadership. Hubble made sure that his accomplishments in college covered all the bases. In his senior year, he even served as vice president of his class, a position he acquired with ease as he shrewdly knew he would be running unopposed.

  After passing the initial Rhodes examination, Hubble became one of the two finalists in Illinois. He may have won the slot once the judging committee saw the glowing letter of recommendation written by Millikan. Hubble had served as a laboratory assistant in Millikan's elementary physics course at the University of Chicago. To Millikan, Hubble was a “man of magnificent physique, admirable scholarship, and worthy and lovable character…. I have seldom known a man who seemed to be better qualified to meet the conditions imposed by the founder of the Rhodes scholarship than is Mr. Hubble.”

  Hubble arrived at Oxford in October 1910, living for the next three years on an annual stipend of fifteen hundred dollars. There he walked the very halls where Edmond Halley once strode and joined a cozy club of privileged young men from England's wealthiest families, who were training for select positions in the military, banking, industry, government, and diplomatic services. With continued pressure from both his father and grandfather, Hubble dutifully studied the law and completed the jurisprudence coursework in two years instead of the usual three. He received second-class honors. But, always in the background, astronomy beckoned. He couldn't let it go, so deep was his passion for the celestial specialty. Sensing it would create a ruckus, he didn't let his parents know that he was cozying up to Oxford's top astronomer, Herbert Turner, visiting his home several times.