Astronomy and Family: The 1945 Eclipse

This post comes as many prepare to head off to hopefully witness a total eclipse tomorrow, April 8, 2024.

There are a couple Princeton connections to the total eclipse that took place on July 9, 1945--one being a "Princeton Party", presumably from Princeton, that journeyed to Montana for the event. The other has to do with a renowned astronomer named Chandrasekhar, whom Princeton sought to add to its faculty the following year. But I primarily want to tell of a familial connection I have to that eclipse nearly 80 years ago.

From a biography of my father, astronomer Al Hiltner: "In 1945 Hiltner and Chandrasekhar went to Canada to photograph a total eclipse of the sun. This represented a unique collaboration with the theorist Chandrasekhar, for I believe that the paper showing those photographs remains the only observational research paper ever published by Subrahmanyan Chandrasekhar." My father had just joined Chandra, a future Nobel Prize winner, on the faculty at the University of Chicago's Yerkes Observatory.

I found these photos, probably taken by my father, online. That may well be the family tent in the background, more often used for canoe trips, with Chandra standing in the foreground, maintaining the formality of a suit in the outback of Manitoba, Canada. 

They had chosen to set up on "a slight ridge commanding a clear view of the eastern sky some five miles southeast of Pine River."

It looks like they even installed a fence around their site, perhaps to discourage cattle or other animals from disturbing their equipment.

The combination of all their preparations and some good luck made for a successful mission:

"On July 9th morning the eastern sky was cloudy, but the drifting clouds produced a clear region some twenty-five minutes before totality. The entire sky clouded over again half an hour later."

By July 1945, Germany had surrendered and Japan would soon thereafter. According to wikipedia, Chandra worked in the Ballistics Research Laboratory at Aberdeen Proving Grounds during WW II. He would surely have collaborated with Veblen, who oversaw scientific work at Aberdeen. That Princeton offered Chandra a position one year later, after Veblen's close friend, Henry Norris Russell, retired, may not be coincidental. Princeton's interest resulted in the doubling of Chandra's salary, as U. of Chicago increased his pay to match Princeton's offer. 

Math and Motion: When Our Limbs Become the Roots of Our Tree of Thought

I was told that Oswald Veblen did his best thinking while chopping wood. Similarly, a daughter of Joe Kohn, the great mathematician who died recently, told me that her father very much disliked reaching the point in aging when he could no longer walk, because walking was so important to his act of thinking. Though I'm not a mathematician, I've had insights and ideas come to me while washing dishes, chopping wood, or more generally when my hands and mind are working together. There is something in the connection between body and mind, as if our arms and legs were the roots of the tree of thought. Of course, the scientist side of my brain is immediately looking for evidence to support or contradict this thesis. Do those who have lost the use of their limbs also have eureka moments?

Recently I felt the urge to ask a mathematician if he did his best thinking while bicycling. The prompt for the question is something of a story. I was walking down the hallway of a medical building, fresh from my annual dermatology exam. There was an older couple walking just ahead of me, and they were disagreeing as to who would drive the car home. He wanted to drive, but she was insisting that she drive, given that he had just received some medication. He said he was just fine, however, and their back and forth seemed headed for an argument. In retrospect, it was as if I were a kid listening to his parents. Something came to mind, and I decided to go with it. Wishing to defuse the situation with some humor, I blurted out from a few feet behind them, "Okay, how about I drive you home?" 

They turned around, still in stride towards the door to the stairwell, and the man responded "Do you drive a stick shift?" This was music to my ears, as I love driving a stick shift. I told him about the '94 Ford Ranger I use for my work at Herrontown Woods, and as we headed down the stairs, we talked stick shifts we'd known, like the "3 on a tree" in my '63 Chevy station wagon--a car that was emphatically beige because my mother was big on beige. We continued to talk as we left the building. I said that when driving a stick shift, the driver must listen closely to the engine. That delicate interplay between clutch and accelerator--it's like a dance with the machine. (Though I didn't mention this, maybe that relationship is why my ear is also attuned to the sound of other machines, like when the furnace kicks on, and the implications for my personal contribution to climate change.)

As we reached my bicycle (I clearly had not thought through the logistics of driving them home), he recounted having taken a bad spill on his bike. He had been biking on Canal Road and gotten so caught up in mathematical thoughts that he didn't notice a pothole. 

My ears perked up when he mentioned math, given of course that I am working to restore Oswald Veblen's house. "Are you a mathematician?," I asked. He responded affirmatively and told me his name. His story fit well with a video a botanist friend of mine had posted a week before on facebook, in which my friend is riding his bike along a broad trail, one hand on the handlebar, the other holding the camera, pointing at different plants and calling out their latin names as he passed by. The video ends abruptly when he falls off of his bike, breaking a couple bones in the process. He's on the mend, but high-speed botany, like high speed math, has its risks.

Biking home, I wished I had asked the mathematician whether he does his best thinking while riding a bike. I looked him up, found his home page, and sent him an email. His response? "I haven't done much good Math thinking while biking. The accident was more than 20 years ago and it taught me to concentrate on biking when on the bike."

Not the answer I was looking for, but all for the best, and a lot more fun than an argument over who is going to drive.

Historical Research Can Uncover Uncanny Coincidence

There are some aspects of my role in adopting Veblen House as a longterm project that border on the uncanny. Coincidence has accumulated as I've researched the people who lived in the house. The Veblen House itself, I realized at some point, has much in common with the house I grew up in. 

That house, next to Yerkes Observatory in Wisconsin, is now also named after a renowned scientist, the astronomer Otto Struve, and is similar in color to what the Veblen House was, and is at the end of a drive, surrounded by woods, 

Also echoing the Veblen House, it's even approached along a slightly curving walkway, down and to the left as one pulls into the driveway. 

Oswald Veblen came to Princeton after growing up in the midwest, as did I, and after having lived in a progression of university towns, as did I. His grandparents emigrated from Norway to Wisconsin, where I spent my childhood. His father's father built houses and barns, as did mine. His father was a physicist, mine an astrophysicist. Veblen got his PhD at the University of Chicago, where my father would later spend most of his career. It's likely that Veblen as a boy of 13 saw the 40 inch refracting telescope my father used--the world's largest refracting telescope--on exhibit at the 1893 world's fair in Chicago. I almost went to Carlton College, where Veblen's father and all of his aunts and uncles got degrees. I spent my childhood roaming the expansive grounds of Yerkes Observatory, where brilliant scientists lived on the outskirts of a small town with school colors orange and black, not unlike the circumstances of the Institute for Advanced Study, which Veblen helped to found on the outskirts of Princeton. 

As if these coincidences aren't enough, there's also the first owners of what would later be called the Veblen House, Jesse and Mary Whiton-Stuart, who lived their last years in towns I have familial connections to--San Luis-Obispo, CA and Tucson, AZ, the latter being where we'd go as part of my father's work at nearby Kitt Peak Observatory.

And then there's the uncanny coincidence that came to light when I began researching the origins of the house in Ann Arbor where I lived for many years. It was built and lived in by Walter Colby, a nuclear physicist who in many ways played the same role at U. of Michigan that Veblen played in Princeton, bringing brilliant scholars from Europe to raise the level of science and math in the U.S. They had parallel lives, born in the same year, retiring the same year, their legacies largely forgotten and in need of rediscovery. Neither had children, and both played important military roles in World Wars I and II. Both were married to women who also led singular lives, and tended to beautiful gardens. 

Ramanujan, Veblen, and Chandrasekhar: After seeing "The Man Who Knew Infinity"

A movie showing in town, "The Man Who Knew Infinity" (trailer here), tells the story of a brilliant but little known Indian mathematician, Srinivasa Ramanujan. Growing up in India, in poverty and with little formal training, he produced a prodigious body of original, unconventional work that ultimately came to light through his persistent efforts to reach out to British mathematicians. Of those he sent excerpts of his work to, only G.H. Hardy of Trinity College, Cambridge, responded, in 1913. A collaboration ensued, with Ramanujan moving to England.

The movie begins with a quote from Bertrand Russell, who is one of the characters: “Mathematics, rightly viewed, possesses not only truth, but supreme beauty—"

There are multiple tensions in the movie: atheism and belief in God, the skepticism of the British mathematicians, racial and institutional prejudice, Hardy's attempts to steer Ramanujan's intuitive explorations of the infinite towards the tedious, earthbound necessity of proofs, the long-distance love for his wife left behind in India, his battles with disease.

Ramanujan was a contemporary of Oswald Veblen, born seven years later, in 1887. Both can be found in descriptions of the "Greatest Mathematicians born between 1870 and 1939 A.D." Though it's not clear if the two ever met, there are several connections between Veblen and the British mathematicians portrayed in the movie. One can find, in the google book "Ramanujan: Letters and Commentary" and elsewhere, that G.H. Hardy exchanged places with Veblen during the year 1928-29, with Hardy coming to Princeton and Veblen spending a year at Cambridge. Though Hardy was not enamored of the study of ballistics, both Veblen and Hardy's close colleague, John Littlewood, joined the military during WW I, in the U.S. and Britain, respectively, to contribute their mathematical expertise to improving ballistics. An interesting article describes Veblen's leading role in bringing a group of mathematicians together at Aberdeen Proving Grounds to work on ballistics. As important as any contribution made to ballistics, the gathering of mathematical minds at Aberdeen "created a community out of a generation of mathematicians" that influenced many of their careers. (Another potentially interesting article encountered is Placing World War I in the History of Mathematics.)

The physical link between mathematics and the human and natural gardens at Veblen House and Herrontown Woods is echoed in IAS faculty member Freeman Dyson's metaphorical praise at the 1987 centenary conference celebrating Ramanujan's contributions to mathematics. From the NY Times:

"Such mathematics has helped drive one of the major new conceptions of theoretical physics, superstring theory, as the physicist Freeman Dyson told a Ramanujan conference last month. 'As pure mathematics, it is as beautiful as any of the other flowers that grew from seeds that ripened in Ramanujan's garden.'"

In a personal aside, Ramanujan's origins reminded me of another Indian, Subrahmanyan Chandrasekhar, who was awarded the 1983 Nobel Prize in physics. He was a colleague of my father's at Yerkes Observatory (the two furthest left in the photo). I remember reading with some surprise, having always framed discrimination in terms of black and white, that Chandra also was the victim of racial prejudice during his long career in England and the U.S.. A look into his biography shows some parallels with Ramanujan. Chandra also studied in Madras, two decades after Ramanujan, and followed the same path to Trinity College in Cambridge, with similarly dramatic results, both in extraordinary contributions and cultural tensions. A 2005 article in the Guardian, Battle for the Black Hole, describes the mistreatment Chandrasekhar is said to have endured, resulting in lasting trauma and a 40 year delay in the recognition he so deserved for his discoveries. Third from the right in the photo appears to be Gerard Kuiper, whose research supported Chandra's theories as far back as 1935. The article says Chandrasekhar's discovery was finally vindicated with the discovery of an x-ray source, Cygnus X-1, in 1972. I remember my father being very involved in studying x-ray sources at that time, specifically Sco X-1, organizing simultaneous observations around the world. Kuiper--fun fact here--was Carl Sagan's doctoral advisor at U. of Chicago.

Additional reading shows that Chandrasekhar was greatly inspired by the career of Ramanujan, and is responsible for having later tracked down the only adequate photo of the great mathematician, taken for the passport prior to his return to India from Great Britain. It's the photo above and at the end of the movie.

No clear connection between Chandra and Veblen has yet emerged, though they must have encountered each other at Aberdeen Proving Grounds, where they both served during WW II along with Von Neumann and others. Both may have seen the possibilities for their own careers through their illustrious uncles, C.V. Raman and Thorstein Veblen. Raman was awarded the Nobel prize in physics. 

Update: In the original post here, I told a story of my parents taking me to dinner at the Chandrasekhars', and how I had been so overwhelmed by the smell of spices spilling out the doorway that I couldn't even enter, and spent the evening outside on the porch, working on an Around the World trick with my yoyo, while the more worldly experience of Indian cooking was going on upstairs. My older siblings tell me that the host was an Indian grad student at Yerkes, not Chandra, who with his wife lived not in town but in a house overlooking Lake Geneva.

My siblings offered some surely more accurate Chandra stories of their own. One offers insight into the sort of departmental politics that can arise out of having so many high-achieving scholars packed into a small community like Yerkes Observatory. Due to a misunderstanding created by another colleague, the department chair was keeping my father's salary low and refusing to promote him to full professor. Suddenly, my father started getting raises. Turned out that Chandra had persuaded the department chair that my father deserved better. 

Chandra dressed impeccably in British formal attire, and his wife, Lalitha (which my siblings pronounce like "Lolita"), wore traditional saris that must have seemed extraordinary in small town Wisconsin.

Another story, which can be obliquely tied to Veblen's ballistics work, involved a game I would play on the observatory grounds, in which I would see how few strokes it took to hit a golf ball all the way around the massive building. It was a challenge to send the ball flying over or inbetween trees, and there were a few times when imperfect execution sent the ball caroming off of the building's tan brick walls. Incredibly, no windows ever got broken in the process. One day, according to my brother, Chandra was passing by on his way home and stopped to talk to me, not to question my dubious pursuits but to explain the purpose of the dimples on the golf ball. Maybe his study of the flow of electromagnetic particles offered insight into how air flows around a golf ball.

In a third story, connected somewhat to Veblen's ballistics and early computer work, Chandra is said to have used top performing female students at my small-town high school in Williams Bay as an early form of "computer", to "calculate immensely difficult mathematical equations entirely by long hand". Based on that experience, he later recommended that female calculators be used to speed up aspects of the Manhattan Project. My sister remembers a Yerkes staff member, Irene Hansen, doing calculations with the aid of a small typewriter-like machine. By brother says it was a Monroe calculator, perhaps like this one, which he says helped him learn multiplication tables. He'd race the machine, and could sometimes beat it as it went "caCHUNKa, caCHUNKa, caCHUNKa". 

George Dyson, in his book Turing's Cathedral (p. 159), describes how scientists' frustration with the limitations of the Monroe calculator led in part to von Neumann's work to develop a high speed computer at the Institute for Advanced Study beginning in the mid-40s. The project was received skeptically by all at IAS but Veblen.  

Irene Hansen, whose various roles at Yerkes included assistant, secretary, and "computer", later married astronomer Donald Osterbrock, who studied with Chandrasekhar and had a post-doc at Princeton. Osterbrock and another Yerkes astronomer, Bill Morgan, contributed to the discovery of the Milky Way galaxy's spiral structure. I like this quote from Osterbrock's obit: "Morgan's methods were sometimes criticized as being "qualitative," and one critic even accused him of being 'a celestial botanist.'" How many of us get to grow up with a celestial botanist as a neighbor?

Interesting to contemplate how a love of nature led to discovering the Veblen House, long forgotten in a Princeton preserve, which led to learning of Veblen's legacy, which led via a movie about an Indian mathematician back to the world I inhabited as a child in Wisconsin.

In the movie, Ramunujan is played by Dev Patel and Jeremy Irons portrays Hardy; Toby Jones plays Hardy’s colleague John Littlewood; Jeremy Northam shows up a few times as Bertrand Russell.

A bit of an afterthought: Note the similarity in appearance between Jeremy Irons in his portrayal of G.H. Hardy

and Veblen late in life. I'm sure Veblen would be majorly flattered by the comparison.

William Albert Hiltner Turns 100

A bit of a personal note. My father, William Albert Hiltner, turns 100 today. (He's on the far left in the photo.) I wish he were still around to celebrate it, but even though he died 23 years ago, the day still has meaning.

Somewhat akin to Oswald Veblen, he became a prominent academic after growing up in midwest farm country, a descendent of farmers and carpenters. Whereas Veblen went to graduate school at the University of Chicago, my father got his first job there some 40 years later, first as an instructor and later as professor of astronomy. In the 1940s, that meant moving to Wisconsin, where U of Chicago had its world famous Yerkes Observatory, with its largest of refracting telescopes and clear, "photometric" winter skies making it a center of research. There's a Wisconsin connection for the Veblens, it having been where Oswald's grandparents first settled after immigrating from Norway. Also like Veblen, my father assumed leadership roles, first as director of Yerkes and later as head of AURA, the Association of Universities for Research in Astronomy.

He loved the outdoors, sailing, and took us on whitewater canoeing trips in northern Wisconsin even though he didn't know how to swim. Some of my fonder memories are of volunteers working together to get the piers and tents ready each year for girl scouts at a camp in northern Wisconsin--the sort of hands-on group effort Veblen may have been getting at when he'd organize colleagues for ventures into the Institute woods to clear brush. Such group effort is rarer today, removed as we are several generations more from the barn raisings of America's rural past.

Among other parallels was the influence that work for the military had on my father's approach to science. This is described in an online bio at the American Astronomical Society website:

"During World War II Al was engaged in the production of front surface mirrors, and in military optics design and modeling, an experience which influenced his later interest in astronomical instrumentation." 

Veblen's vision for an institute for advanced study was influenced by the informal atmosphere he found while working at a military proving grounds to improve ballistics during WWI. It was also the vast computations required to create trajectory tables for artillery that gave Veblen an appreciation for early computer designs.

My father's passion for his work extended from research, to teaching, to the hands-on aspects of instrument design. He maintained a youthfulness and inquisitiveness to the end, learning to swim at age 64, and spending the last seven years of his life as project manager for the Magellan Project, designing twin telescopes to be built on a mountain in Chile. 

These qualities are shared by Veblen, who made important contributions to mathematics but also lent early support to computer research, at a time when the potential of computers was far from obvious. Quoting from Deane Montgomery's obituary for Veblen in the Bulletin of American Mathematics, 

"Veblen remained rather youthful in his point of view to the end, and he was often amused by the comments of younger but aging men to the effect that the great period for this or that was gone forever. He did not believe it. Possibly part of his youthful attitude came from his interest in youth; he was firmly convinced that a great part of the mathematical lifeblood of the Institute was in the flow of young mathematicians through it."

It's this forward looking point of view, this capacity to see a path forwards and willingness to take on all the obstacles in that path, that I most admire in these men, and those who are working together to preserve and repurpose the house and farmstead the Veblens left to the public trust.