The Day We Found The Universe

Interview With Marcia Bartusiak


Marcia Bartusiak is a popular science writer and author of numerous books including; Thursday’s Universe, Through a Universe Darkly, and Einstein’s Unfinished Symphony. She writes frequently on science matters for magazines such as Astronomy, Science, Smithsonian and Discover. She is a two-time winner of the American Institute of Physics Science Writing Award and teaches in the graduate program in science writing at Massachusetts Institute of Technology. Her current book, The Day We Discovered the Universe, (Random House) tells the story of the discovery of the modern universe and profiles the array of people responsible. Freelance journalist Aaron Leonard [] recently discussed her new book with her by phone.



You start this book quoting the astronomer Simon Newcomb in 1887 saying, “So far as astronomy is concerned...we do appear to be fast approaching the limits of our knowledge...The result is that the work which really occupies the attention of the astronomer is less the discovery of new things than the elaboration of those already known and the entire systemization of our knowledge.” Then on the next page you make the counter point that Harlow Shapley and Edwin Hubble upset Newcomb’s paradigm -- if you will -- by pursuing a “question that few others were asking.” What were the questions Shapley and Hubble pursued, and what lead them to ask them?


Every since the time of Newton and on into the 19th century astronomy was basically concerned with tracking the motion of stars and planets. That was their reason to live. Not only for navigational things but also to continue to prove Newton’s theory. They really wanted to focus on stars and planets. Any other object, like nebulae, were considered a sideline, not terribly interesting and important. It was only in the late 19th Century and in the beginning of the 20th Century that suddenly these new celestial objects started to take on interest, but still by very few astronomers. I mention this one astronomer in my book, James Keeler, who really made it his life’s work to focus on the nebulae. Not only to photograph them, but to track their motion. He started to think of them as an interesting object to study. Other astronomers still considered it a sideline. The “important” astronomy were those people who were surveying the heavens and counting the stars. Showing where they were positioned, what is their luminosity, what is their spectra. That was the “important” work in astronomy.


It was just these young astronomers coming in, who wanted to make their mark and look at something interesting and different--who looked beyond what was being done day, by day, by day in the ranks of regular astronomers.


Shapley and Hubble were coming to the question of the nebulae because they were, as young Turks, sensed ‘there may be gold in them thar hills’. Especially Hubble.


Hubble was very influenced by attending a very important meeting by the American Astronomical Society in 1914 in which Vesto Slipher announced his great results in trying to find the speed of these spiraling nebulae. It was a very difficult astronomical task. All the astronomers knew it. Yet he had found, I think up to that point, fourteen speeds, and they were all very interesting. They were going at terrific speeds, up to a thousand thousand kilometers a second away from Earth. At that point people were still not sure what they were. Were they just gaseous clouds? Were they outside the Milky Way? That wasn’t known yet. But this was ten times faster than any recorded velocity of a star within the Milky Way.


Hubble was in the audience, he was about to start his graduate work at Yerkes Observatory, at the University of Chicago. I think he was greatly influenced by this. He sensed, I think, that by studying the spiraling nebulae he might get fame and fortune and great prestige within his newly adopted field of astronomy.


Shapley also, was very ambitious and was not interested in studying obvious problems. Slipher was doing it because his boss asked him to do it, but he stumbled onto this great problem.


These were ambitious men. I think that is why they chose problems that were off the beat-in path. They sensed that there was a high probability of getting something interesting out of it.


You seem to be doing two things with this book, telling the story of how we’ve come to our current understanding of the universe, but also describing a fuller cast of characters who were responsible for that understanding. You talk about Shapley, Hubble and Einstein but also tell us about the wealthy businessmen Percivial Lowell and James Lick. And you talk about the pathbreaking work of the scientist Vesto Slipher, the farsighted insights of Russian scientist, Alexsandr Freidmann, and even the arduous work of Hubble’s assistant Milton Humason. Why do you see them as such a key part of this story?


As a writer I was looking to write the definitive narrative history. I wanted to show the complete story of how it came to be that we learned one, that there were indeed other galaxies beyond the Milky Way and two, that the universe is expanding. That the universe was far different that what we had known for centuries before, which was simply this collection of stars known as the Milky Way somehow suspended in this void of unknown depth.


I saw that unique period 1900-1930, when all this happened as being a very rich story. I wanted to show something other than the standard textbook summary. When you summarize history in these little bites they tend to get very simplified, ‘oh there’s these new telescopes, Hubble goes to the 100 inch telescope on Mount Wilson, looks through the eyepiece and sees this whole new universe...’


I wanted to show that’s there is far more than this. That Hubble was the culmination of decades of work by others. He gets credit for finding the definitive proof but there were others that were slowly building up the evidence. I wanted to impart that full story.


I also wanted to show that this was a unique moment in time. I called it the perfect storm; of the economy, technology and theory coming together to bring this moment to fruition.


First of all it was the height of the Guilded Age. Industrialists were making oodles of money. They wanted to make their mark in philanthropy, to give something back, but also build up their name. All the great philanthropists of that era, Andrew Carnegie, James Lick, John D. Rockefeller were deciding that building observatories on a mountain was a great way to get attention for themselves. The great dome on the mountain where everyone could look up and see what they had done to further science. It was a great monument to themselves. Astronomy came to be the preferred way to donate their money to science at the time.


At the same time it was this moment of great technological advancement. It was a turning point in advancing telescope technology. They were adding cameras to the telescope, they were now able to build huge telescopes for the time. These mirrors--which at the time was not the preferred method--the technology had been sufficiently advanced that they could build telescopes of tremendous size which enabled the astronomers to look further and further outward.


And it was the moment when Einstein was coming onto the scene with his wonderful General Theory of Relativity, which could be applied to the universe at large and finally explain the universe’s behavior from a theoretical viewpoint.


It was this great coming together. From the riches from the great industrialists funding the great advances in technology that enabled these telescopes and instruments on high mountains which gave astronomers a far far better view than being on the ground at ocean level which had been done in the past. Then we have now a theory which they are able to use the universe to test Eienstein’s theories to understand the behavior of the universe. It all came together at this moment in time.


It was more than Hubble. It was a whole cast of characters that brought this together. I wanted to show how this was not a singular event but a collective endeavor.


The contrast between Hubble and Shapley is stark, could you talk about their approaches, and more specifically, where’s the line between audacious and reckless?


They represent two ends of the spectrum of how you can deal with science. I believe it comes from their backgrounds.


Shapley was a brash farm-boy. He was a former crime reporter. He was used to nosing in, getting the facts, and going back with a great story. He was a storyteller. He liked to think in the grand view. The particular details? ‘We’ll wrap them up later.’


Versus Hubble who came from a middle class background. His father was trained in the law -- though he worked for an insurance agency, his families business. He hated the idea of Hubble majoring in astronomy. He forced Hubble to prepare for the law which he thought of as a much better profession for his son. So Hubble did both, he studied law as an undergraduate, but also took science courses. He was a Rhodes scholar, went to Oxford. His father again, did not want him studying science, at Oxford. Hubble dutifully studied law at Oxford--though he did make sure he maintained contact with the astronomers there on campus.


Hubble was more cautious, more dutiful, and obeyed authority. He was nonetheless terribly terribly ambitious and had a good nose for an interesting problem. In his science he was taking these aspects of his personality-- his cautiousness and his training in the law--which I think gave him great respect for evidence and making sure you had airtight case.


This made him overly cautious. He held back a full year after finding evidence that Andromeda and other nebulae were truly distant, outside the Milky Way. He held up publishing in order to nail down every possible argument against it.


Compared to Shapley. When he learned about something, he went right to the bullhorn. He wanted to get the news out. The little details, the little problems, were not so much his concern. He always wanted to see the grand picture. He would build up grand pictures based on minimal evidence.


In may ways he was right, and in other ways he was wrong. His brashness, his stubbornness to hold to these grand pictures made him lose the honor of doing what Hubble did. He could have beat Hubble to learning that the Andromeda Galaxy was far, far out. He had the opportunity, he had the smarts, he was the world’s expert on Cepheid variables. He could have taken the work he was doing within the Milky Way--which was using Cepheid variables to size up the Milky Way--he could have gone on to look for that evidence. But he was so mulishly wedded to his model, that Hubble was able to step in and take that away from him.


It’s interesting, they were the yin and yang of science. They literally hated one another. They needed one another. Shapley went on to become director of the Harvard college observatory, which had the greatest collection of photographs in the world. Hubble was using the world’s biggest telescope, using the same techniques in searching for Cepheids but now in spiral nebulae rather than globular clusters. He needed Shapley to give him backup with those photographs. Shapley needed Hubble’s backup from the information he was gaining from the biggest telescope in the world. They needed each other.


These are two type of personality you see all the time in science the ones who will rush ahead with their ideas before the evidence is fully in. Sometimes this helps get a field going. Some people are lucky in that way, they make that lucky guess. Others are more careful. Darwin was that way. Darwin held onto his data and wold not publish until he was absolutely sure, until he knew that Wallace was coming in to supplant him. Then suddenly he did publish. And Newton was the same way. Newton didn’t publish all the knowledge he had about the way gravity worked until he knew there was this threat from others coming and he wanted to make sure he got the credit. You see this all the time in science.


There’s this passage in your book where you describe a visit by the English poet Edith Stilwell to Hubble's home where she is shown slides, “depicting the myriad galaxies that cannot be seen with the naked eye, galaxies million of light-years away. “How terrifying!” exclaimed Stillwell, to which Hubble replied, “Only at first. When you are not used to them. Afterward, they give one comfort. For then you know that there is nothing to worry about--nothing at all!” At the risk of taking the poetry out of that response--what do you understand Hubble to be saying?


I was struck by it as well as to how do you interpret this? On the one side you cold think of this, as after time you get used to this new knowledge and you get comfortable with it. Just as we over time have always adjusted to the advances in our knowledge of the universe; first its just the solar system, then we understand that no, we are part of the Milky Way and that’s fairly big, the suddenly you have to adjust to this idea that the Milky Way is but one of billions of other galaxies, okay over time we adjust to that. Sort of the way your first airplane flight may be very frightening but after a while you take it for granted that you can fly in this plane somehow and go thousand of miles.


Then there’s another side I think he may have been talking about -- and wouldn’t it be nice if Hubble were living so we could ask him exactly what he meant--I am wondering if its the sense that you are learning that the universe is immense. That the earth is really the equivalent of this subatomic particle in this vast immensity. So why should we worry about our earthly problems? They are so miniscule compared to this magnificent vastness. So relax...after a while its comforting. After a while what you consider vast problems on earth are trivial compared to our true place in the cosmos.


copyright ⓒ2009 Aaron Leonard