Arno Penzias


I was born in Munich, Germany, in 1933. I spent the first six years of my life comfortably, as an adored child in a closely-knit middle-class family. Even when my family was rounded up for deportation to Poland it didn’t occur to me that anything could happen to us. All I remember is scrambling up and down three tiers of narrow beds attached to the walls of a very large room, and then taking a long train trip. After some days of back and forth on the train, we were returned to Munich. All the grown-ups were happy and relieved, but I began to realize that there were bad things that my parents couldn’t completely control, something to do with being Jewish. I learned that everything would be fine if we could only get to “America”.

In the late spring of 1939, shortly after my sixth birthday, my parents put their two boys on a train for England; we each had a suitcase with our initials painted on it, as well as a bag of candy. They told me to be sure and take care of my younger brother. I remember telling him, “jetzt sind wir allein” as the train pulled out.

My mother received her exit permit about a month later (just a few weeks before the war broke out) and was able to join us in England. My father had arrived in England almost as soon as the two of us, but we hadn’t seen him because he was interned in a camp for alien men. The only other noteworthy event in the six or so months we spent in England, awaiting passage to America, occurred one morning in a makeshift schoolroom. At that moment, I suddenly realized that I could read the open page of the (English) school book I had been staring at.

We sailed for America toward the end of December 1939 on the Cunard liner Georgic – using tickets that my father had foresightedly bought in Germany a year and half earlier. The ship provided party hats and balloons for the Christmas and New Year’s parties, as well as lots of lifeboat drills. The grey three-inch gun on the aft deck was a great attraction for us boys.

We arrived in New York in January of 1940. My brother and I started school and my parents looked for work. Soon they became “supers” (superintendents of an apartment building). Our basement apartment was rent free and it meant that our family would have a much-needed second income without my mother having to leave us alone at home. As we got older and things got better, we left our “super” job and my mother got a sewing job in a coat factory; my father’s increasing wood-working skills helped him land a job in the carpentry shop of the Metropolitan Museum of Art. As job pressures on him eased, he found time to hold office in a fraternal insurance company as well as to serve as the president of the local organization of his labor union.

It was taken for granted that I would go to college, studying science, presumably chemistry, the only science we knew much about. “College” meant City College of New York, a municipally-supported institution then beginning its second century of moving the children of New York’s immigrant poor into the American middle class. I discovered physics in my freshman year and switched my “major” from chemical engineering to physics. Graduation, marriage and two years in the U.S. Army Signal Corps, saw me applying to Columbia University in the Fall of 1956. My army experience helped me get a research assistantship in the Columbia Radiation Laboratory, then heavily involved in microwave physics, under I.I. Rabi, P. Kusch and C.H. Townes. After a painful but largely successful struggle with courses and qualifying exams, I began my thesis work under Professor Townes. I was given the task of building a maser amplifier in a radio-astronomy experiment of my choosing; the equipment-building went better than the observations.

In 1961, with my PhD thesis complete, I went in search of a temporary job at Bell Laboratories, Holmdel, New Jersey. Their unique facilities made it an ideal place to finish the observations I had begun during my thesis work. “Why not take a permanent job? You can always quit,” was the advice of Rudi Kompfner, then Director of the Radio Research Laboratory. I took his advice, and remained a Bell Labs employee for the next thirty seven years.

Since the large horn antenna I had planned to use for radio-astronomy was still engaged in the ECHO satellite project for which it was originally constructed, I looked for something interesting to do with a smaller fixed antenna. The project I hit upon was a search for line emission from the then still undetected interstellar OH molecule. While the first detection of this molecule was made by another group, I learned quite a bit from the experience.

In order to make some reasonable estimate of the excitation of the molecule, I adopted the formalism outlined by George Field in his study of atomic hydrogen. To make sure that I had it right, I took my calculation to him for checking. One of the factors in that calculation was the radiation temperature of space at the line wavelength, 18-cm. I used 2 K, a somewhat larger value than he had used earlier, because I knew that at least two measurements at Bell Laboratories had indications of a sky noise temperature in excess of this amount, and because I had noticed in Gerhard Hertzberg’s “Spectra of Diatomic Molecules” that interstellar CN was known to be excited to this temperature. The results of this calculation were used and then forgotten. It was not until Dr. Field reminded me of them in December of 1966 that I had any recollection of my momentary involvement with what was later shown (by Field and others) to be observational astronomy’s first encounter with the primordial radiation that permeates our Universe.

In the meantime, others at Bell Labs pressed the horn antenna into service for another satellite project. A new Bell System satellite, TELSTAR, was due to be launched in mid-1962. While the primary earth station at Andover, Maine, was more or less on schedule, it was feared that the European partners in the project would not be ready at launch time, leaving Andover with no one to talk to. As it turned out, fitting the Holmdel horn with a 7-cm receiver for TELSTAR proved unnecessary; the Europeans were ready at launch time. This left the Holmdel horn and its beautiful new ultra low-noise 7-cm traveling wave maser available to me for radio astronomy. This stroke of good fortune came at just the right moment. A second radio astronomer, Robert Wilson, came from Caltech on a job interview and was hired. After finishing separate projects, we set to work early in 1963.

In putting our radio astronomy receiving system together we were anxious to make sure that the quality of the components we added were worthy of the superb properties of the horn antenna and maser that we had been given. We began a series of radio astronomical observations, ones that I had proposed so as to make the best use of the careful calibration and extreme sensitivity of our system. Of these projects, the most technically challenging was a measurement of the radiation intensity from our galaxy at high latitudes. This multi-year endeavor, which resulted in our discovery of the cosmic microwave background radiation, is described in Wilson’s Nobel lecture.

When our 7-cm program was accomplished, we converted the antenna to 21-cm observations, including another microwave background measurement, as well as galactic, and intergalactic, atomic hydrogen studies. During this period, I took on a visiting position in Princeton’s Astrophysical Sciences Department, thereby enabling me to propose and supervise graduate student research projects in radio astronomy. Like so many others in similar positions, I feel that I learned far more from my students than I could possibly have taught them.

As time went on, opportunities for front line work that we could do with our facility became rarer. Much larger radio telescopes existed, and they were being fitted with low-noise parametric amplifiers whose sensitivities began to approach that of our maser system. As a result, I began looking for new ways of exploring the radio sky. In those days, the portion of the radio spectrum short-ward of one cm wavelength was not yet available for line radio astronomy owing to equipment limitations. At Bell Laboratories, however, many of the key components required for such work had been developed for communications research purposes. With Keith Jefferts, a Bell Labs atomic physicist, Wilson and I assembled a millimeter-wave receiver which we carried to a precision radio telescope built by the National Radio Astronomy Observatory at Kitt Peak, Arizona, early in 1970. Using this new technique, we discovered and studied a number of interstellar molecular species, thereby revealing the rich and varied chemistry which exists in interstellar space.

Millimeter-wave spectral studies have proven to be a particularly fruitful area for radio astronomy, and are the subject of active and growing interest, involving a large number of scientists around the world. The most personally satisfying portion of this work for me was using molecular spectra to explore the isotopic composition of interstellar atoms – thereby tracing the nuclear processes that produced them. Most notably our 1973 discovery of DCN, the first deuterated molecular species found in interstellar space, enabled me to trace the distribution of deuterium in the galaxy. This work provided us with evidence for the cosmological origin of this unique element, which had earned the nickname “Arno’s white whale”. Of all the nuclear species found in nature, deuterium is the only one whose origin stems exclusively from the explosive origin of the Universe. Because deuterium’s cosmic abundance serves as the single most sensitive parameter in the prediction of cosmic background radiation, these measurements provided strong support for the “Big Bang” interpretation of our earlier discovery.

In addition to my astronomical research, I always had made it my business to engage in technology-related work at Bell Labs. It seemed only reasonable to contribute to the pool of technology from which I drew upon. Similarly, Bell Labs has always contributed to, as well as used, the store of basic knowledge – as evidenced by their hiring of a radio astronomer in the first place.

As time went on, I grew more involved in leading the research of others. In 1972 I became the Head of the Radio Physics Research Department upon the retirement of A.B. Crawford, the brilliant engineer who had designed and built the horn antenna that Wilson and I used in our discovery. In 1976, I became the Director of the Radio Research Laboratory, an organization of some sixty scientists and engineers, engaged in a wide variety of research activities, principally related to the understanding of radio and its communication applications. At the same time, I was able to continue my personal research work in radio astronomy, using a superb millimeter-wave radio telescope we had built at our Crawford Hill facility. Fitted with uniquely-sensitive detectors and a dedicated minicomputer (then still something of a rarity), this facility eliminated the manual controls and constant tinkering with equipment, that I had long been used to.

Early in 1979, my managerial responsibilities increased once again when I was asked to assume responsibility for Bell Labs’ Communications Sciences Research Division. At the same time, I continued the personal research which traced the effects of nuclear processing in the Galaxy through the study of interstellar isotopes, and began working in a new area – the nature and distribution of molecular clouds in interstellar space. Instead of participating as actively as I had in the past, however, I introduced this subject to graduate students who explored it in their PhD theses under my supervision.

Then, toward the end of 1981, an unexpected event imposed an abrupt end to my career as a research scientist. At that time, AT&T and the US Department of Justice decided to settle their anti-trust suit by breaking up the Bell System. In the midst of this process, I received yet another promotion – this time to Vice-President of Research – at a moment when two-thirds of the traditional research-funding base moved off with the newly-divested local telephone companies.

As a result, I found myself facing several issues at once: What sort of research organization did the new AT&T require? How to create this new organization without destroying the world’s premier industrial research laboratory in the process? Would the people in this large and tradition bound organization accept and support the changes needed to adapt to new economic and technological imperatives? Needless to say, such matters kept me quite busy.

In retrospect, the research organization which emerged from the decade following the Bell System’s breakup deployed a far richer set of capabilities than its predecessor. In particular, our work featured a growing software component, even as we strove to improve our hardware capabilities in areas such as light-wave and electronics. The marketplace upheaval brought forth by increased competition helped speed the pace of technological revolution, and forced change upon the research and development institutions of all industrialized nations, Bell Labs included. While change is rarely comfortable, I am happy to say that we not only survived but also grew more capable in the process – seeding much of the information revolution which now pervades the world in which we live.

Except for two or three papers on interstellar isotopes, my tenure as Bell Labs’ Vice-President of Research brought my personal research in astrophysics to an end. In its place, I pursued my interest in the principles which underlie the creation and effective use of technology in our society, and eventually found time to write a book on the subject Ideas and Information, published by W.W. Norton in 1989. In essence, the book depicts computers as a wonderful tool for human beings but a dreadful role model for what we humans know as intelligence. In other words, “If you don’t want to be replaced by a machine, don’t try to act like one!” The warm reception this book received in the US, and the ten other countries which published it in various translations gave me much satisfaction.

By the early 1990’s, my life had settled into a familiar – if not entirely comfortable – routine. The joy and satisfaction that I found in helping to help shape exciting new ideas was offset by onerous management chores – most notably, my annual task of getting adequate financial support for my organization’s budget requirements from our parent corporation. Beset by competitors who didn’t have research labs of their own to pay for, AT&T’s leaders nonetheless did their best to provide for its “crown jewel”. As one year followed another, I did my best to repay that trust by helping to turn some of our scientific “gems” into profitable jewelry.

And then, I did something that surprised everyone – myself included. I decided to swap my job for something entirely new, moving from the world’s largest corporate R&D organization to California’s Silicon Valley, premier incubator of tiny start-up enterprises.

In retrospect, I can point to a number of contributing factors – most notably obligatory retirement age, then only a few years away. While arbitrary, the notion behind an age cutoff for senior managers had much to recommend it. I couldn’t (and still can’t see) myself ever being happy without something challenging to work on. Since getting another management-related job seemed too much of the same thing, I hit upon the idea of turning what I had been enjoying most into a full time job: helping to shape new ideas, and bring them to practical fruition. The more I thought about it, the more attractive this plan for my post-retirement life became. So attractive, in fact, that I soon decided not to wait much longer to put it into place.

Once decided upon, my transition proved surprisingly easy. At the suggestion of the then Bell Labs President, I soon took on a new job – one in which I was to report what I learned about Silicon Valley and its workings, to my Bell Labs colleagues. Accordingly, I arranged to sit in on presentations made by nascent start-up enterprises to venture capitalists. I felt right at home in short order, peppering presenters with questions and suggestions concerning their technologies and plans for turning their offers into viable businesses.

As time went on, an increasing number of these sessions led to invitations from some of the entrepreneurs to get directly involved with their companies, generally by becoming a member of a Board of Directors, or serving on a Technical Advisory Board. I accepted a few of these invitations, but then opted for something that seemed more flexible: working on an as-needed basis with the investing staff and portfolio companies of a single venture capital firm: New Enterprise Associates. Happily, this relationship has endured, and continues to flourish to the time of this writing, almost ten years after it began. This talented and diverse group of people works as a successful laboratory – finding ways in which small handfuls of creative people might change some aspect of the world.

In my early years with NEA, much of my interest focused on communications-related endeavors, but soon broadened to encompass a wide variety of topics under the general heading of “Information Technology“. Most recently, I have found and catalyzed several alternative approaches to energy generation – a field I had all but given up on a decade earlier.

With exciting projects underway, and a never-ending stream of new opportunities, my days are filled with new things to learn, challenging puzzles, and stimulating interactions with collaborators. Needless to say, I have no plans to retire.

* This autobiography was provided by the Laureate in June 2005.

Arno Penzias died on 22 January 2024.

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