Blog #1 | December 7, 2025
On Origins and Audacity
Quasar Pioneers
Margaret and Geoffrey Burbidge
and
The First Book of Quasars
by Christopher W. Churchill
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We all love a good origin story. Whether it encompasses experimental serendipity, genius insight, or an inspired theoretical breakthrough, we embrace the feeling it gifts us --- of belonging. We connect to the birthing of new knowledge; we connect with the discoverers and those who built on their work; we connect with our contemporary colleagues through a shared cultural experience.
One aspect of origin stories is that we glorify certain individuals into our lore. Show me an astronomer who does not know the name Edwin Hubble nor his work and its impact on modern cosmology. What physicist does not know the names Galileo, Isaac Newton, and Albert Einstein and revel in their mythological heroism?
Here, we wish to honor pioneers who are less familiar. These are two scientists engaged in the origin story of the discovery of quasi-stellar objects, or quasars. I am speaking of Margaret and Geoffrey Burbidge
Margaret Burbidge
Margaret Burbidge
She was one of the great observational astronomers of the twentieth century and an expert at the interpretation of spectroscopic data.
image credit: University of Chicago Photographic Archive
Geoffrey Brubidge
Geoffrey Brubidge
A Bruce Medalist (1999), he was a flamboyant and outspoken astronomer who challenged his colleagues on all aspects of astrophysics.
image credit: Sonoma State University
In case of quasars, the origin story is that bright (and mysterious) radio sources were being discovered throughout the 1950s. Near the end of that decade, their optical counterparts were being chased down in attempt to associate them with something we might understand. By 1960, it seemed that those mysterious radio sources were star like --- or at least they looked like stars. The first such object under scrutiny was known as 3C 48. The 3C indicates the Third Cambridge Catalog of Radio Sources and the 48 indicates that it was the 48th such source listed. Alan Sandage and Thomas Matthews are pretty much credited with having taken the first spectrum of this “star” and noting that it did not have a star-like spectrum at all. Whereas a typical star has a somewhat thermal continuum and hydrogen Balmer absorption lines, 3C 48 had a rapidly rising blue continuum and emission lines that defied identification. Fast forward through a few years and Martin Schmidt was able to decode the emission lines in the quasi-stellar source 3C 273. He realized that they were significantly redshifted Balmer lines. His discovery was announced in March 1963. This is the essence of our quasar origin story.
March 1963, Marteen Schmidt decodes the spectrum of 3C 273. He measured a redshift of z=0.153. It instantly became the highest known redshifted object.
The New York Times
The spectrum of 3C 273 showing its redshift Balmer lines and its increasing blueward flux. Schmidt's interpretation of the emission lines was soon applied to 3C 48, which was found to have a redshift z=0.348 and instantly more than doubled the highest known redshift for a quasar.
image credit: Gene Smith, UCSD
Long story made short, a new class of object had been found which was soon realized to be a population of highly active supermassive black holes in the nuclear regions of galaxies; well, maybe not so soon realized, but certainly that is our current understanding of these objects. For the next years following Schmidt’s announcement, quasar science was a flurry of “find the optical counterpart,” “point the telescope,” “take the spectrum,” and then “scratch your head.” The quest was on to just try to figure out what these things were. Higher and higher redshift objects were popping up. Soon absorption lines were seen peppered amongst the emission lines. Then broad absorption lines were seen just blueward of some of the emission lines. A great debate raged fueled by questions such as “What is the nature of the large redshifts for these objects?” “Are the absorption lines all associated with material around the quasars?” Just exactly what causes the very large and broad emission lines?”
By late 1966, the spectra and redshift for roughly 100 quasars had been acquired. The data were extracted from non-linear photographic plates using intensity scanners. By today’s standards, it comparatively could have been the bronze age. New information was coming hard and fast, and it was mind boggling. Some quasars had redshifts has low as z=0.1 and others as high as z=2. No quasar had a blueshift. Some quasars had absorption lines, some didn’t. Some were broad, others narrow. Some were at the redshift of the quasar; others were at redshifts much lower than the quasar. The number of absorption lines seemed to be greater in the higher redshift quasars. Some quasars varied in brightness on the order of days, others took months; some didn’t vary at all. In this climate, ideas came and went like the game Whack a Mole.
In 1966, Margaret and Geoffrey Burbidge had set out to organize every piece of data they could get their hands on. And they had access to all of it. Then, they got an audacious idea--- why not organize their findings and ideas into a book? They acknowledged, “as observations have accumulated, it has become clearer and clearer that these [quasars] are indeed a completely new class of object with no parallel in known astronomical phenomenon.” They continued, “In view of the complexities and uncertainties in this field, one might ask whether it is a good idea to attempt to write a monograph at this time. Our first reason for doing this was a purely selfish one: we wished to collect together in a coherent fashion as much of the observational material as we could and see how it could be fitted together at this early stage. Though the field is changing rapidly we thought it might be useful to publish this account of things as they appear to us at the beginning of 1967.” In a confession of the vortex of uncertainty, they warn the reader, “it will be seen from the discussion in the latter chapters that there are so many conflicting ideas concerning theory and interpretation of the observations that at least 95% of them must indeed be wrong. But at present, no one knows which 95%.”
The book covers 18 chapters in 220 pages. Everything is covered from their discovery to their spectral energy distributions to their proper motions. Models of the emitting regions were described and compared, as were correlations with redshift and contrasting ideas of quasars as local phenomena versus association with external galaxies. A focal point of the book is the nature of their redshifts. History has shown that Geoffrey Burbidge was a long-term proponent of non-cosmological quasar redshifts, instead preferring alternative explanations such as local objects ejected from the Galaxy. Much of this was based on an aversion to the tremendous energy budgets required if quasars were at cosmological distances.
The first book summarizing quasars published in 1967 by the team Margaret and Geoffrey Burbidge.
photo credit: the author
First page of the table of contents of the 1967 book Quasi-stellar Objects.
photo credit: the author
Second page of the table of contents of the 1967 book Quasi-stellar Objects.
photo: the author
Chapter 18 is a gem that has aged like a fine wine. While admitting personal preferences to some ideas, the professed honesty of ignorance is beautiful science in motion as the pros and cons of key accountings are methodically summarized. Any scientists hungry for an unveiling of the true scientific grit underlying the origin myths of quasars and the field of quasar absorption lines will devour these few pages with unabated joy. Margaret and Geoffrey do not disappoint. This is a pioneering legacy contribution that keeps giving.
With sixty years behind us and with four generations of astronomers having worked on the topic, the fundamental questions tackled by team Burbidge may seem trivial to us now. But make no mistake, quasars represented a new astronomical phenomenon. They represented a challenge to the status quo of the universe in the modern age. And yet Margaret and Geoffrey Burbidge had the audacity to summarize everything that was known within the first three to four years into a book which they simply called “Quasi-stellar Objects.”
This blog has been fully written by the author. There has been no AI assistance.
60 Years of Quasars in Two Volumes
Order Your Copies Today!
Volume 1 : Cambridge university Press | Amazon
Volume 2 : Cambridge university Press | Amazon
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