In her calm, deliberate way, astrophysicist Jocelyn Bell Burnell has always been in the business of changing worlds. Over a storied four-decade career, she has helped expand our understanding of the universe, caused people to rethink how Nobel Prizes are awarded, and used her stature to fight sexism in the world of science.
Burnell made her first scientific mark in 1968 as Jocelyn Bell, an unknown, 23-year-old doctoral student from Northern Ireland. After months of using the new radio telescope at the University of Cambridge, she came upon inexplicable, metronomically regular radio blips from isolated spots in the sky. Bell and her Ph.D. supervisor, Antony Hewish, concluded that the blips came from hitherto unknown objects, massive yet remarkably small. Because of their pulsed signals, these objects were dubbed pulsars. Soon after, pulsars were identified as rapidly spinning neutron stars, the remnants of supernova explosions; they weigh as much as the sun but are just a dozen miles wide. The discovery was so significant that the Nobel Committee recognized it with a share of the 1974 prize in physics—an honor that was presented to Hewish but not to the young woman who had made the initial observation, Jocelyn Bell. The snub made international news.
Time magazine hyped it as “A Nobel Scandal?” But Burnell was philosophical. “I believe it would demean Nobel Prizes if they were awarded to research students, except in very exceptional cases,” she later said, “and I do not believe this is one of them.... I am not myself upset about it—after all, I am in good company, am I not?”
During the 1970s and 1980s, Burnell went on to work in gamma-ray astronomy at the University of Southampton, X-ray astronomy at University College London, and infrared astronomy at the Royal Observatory in Edinburgh. In the 1990s she made a series of groundbreaking observations of the still-mysterious binary star system known as Cygnus X-3. All the while, her quiet achievements continued to break boundaries. When she became a full professor at the Open University of London in 1991, it doubled the number of female full professors of physics in the United Kingdom. In 2007 she was made a Dame of the Order of the British Empire by Queen Elizabeth in recognition of her contributions to science. Currently Burnell is a visiting professor of astrophysics at the University of Oxford; a professorial fellow at Mansfield College, Oxford; and president of the Institute of Physics in London, where DISCOVER caught up with her in her office.
Astronomy was part of your life from the beginning. Your father was the architect for the Armagh Observatory southwest of Belfast, right?
Yes. The observatory has both a 200-year-old building and newer buildings. As observatory architect, my dad was partly concerned with the maintenance of them all. I used to go with him on site visits quite often, from age 7 or 8. I have memories of crawling through the rafters of the old building, trying to find where the leak in the roof was. I probably know the rafters of that observatory better than the astronomers who worked there.
So you were involved in astronomy before you even realized it.
I don’t know how much influence that had, but I clearly knew of astronomy as a subject and an occupation. When I declared an interest in it, the staff showed me the telescopes and told me what it was like being an astronomer. And they thoroughly put me off. They were optical astronomers, and they worked at night. When they said to me, a teenager who loved her bed, that you had to be able to stay up at night, I knew I couldn’t. So I thought, “Hmm, maybe I can’t be an astronomer.” I then discovered radio astronomy and X-ray astronomy. These things were developing at that time. So I thought, “Right, then I can be a radio astronomer.”
That was your prime motivation—a good night’s sleep?
[Laughs.] It was a large consideration. The ironic thing is that at the point where we were discovering pulsars, I was working quite a few nights because that was when the pulsar was in the telescope beam.
And radio astronomy was so new at the time that you had to build your own radio telescope at Cambridge.
I was actually putting together the telescope. It covered four and a half acres. We put up over 1,000 posts and strung more than 2,000 dipole antennas between them. The whole thing was connected by 120 miles of wire and cable. We did the work ourselves—about five of us—with the help of several very keen vacation students who cheerfully sledge-hammered all one summer. It was a primitive type of telescope, as you would expect in the early days of the field. Radio astronomy was new then. It arose from World War II radar.
How did your radio telescope work?
The output from the telescope appeared on four three-track pen recorders as a squiggly red line on moving chart paper. The telescope produced 100 feet of chart paper every day. One complete scan of the sky took four days, or 400 feet of paper. I was responsible for analyzing this. In the six months I operated the telescope, we recorded several miles of chart.
What led to your discovery of the first pulsar?
My thesis project was to identify quasars, which are very distant, very energetic objects, and still quite mysterious. Some of the squiggles were what I was looking for, and some were radio interference. But there was another bit of squiggle that didn’t make sense. It took up about a quarter-inch out of 400 feet of chart paper. I think the first few times I saw it, I noted it with a question mark. But your brain remembers things you don’t realize it remembers. By about the fourth or fifth time I came across this signal, my brain said, “You’ve seen something like this before.”
