Radio Pulsars, Joy Division, And Jocelyn Bell Burnell

By John Oncea, Editor

Professor Dame Jocelyn Bell Burnell discovered radio pulsars, one of the most important astronomical discoveries of the 20th Century. She has received numerous awards and honors and is a devoted advocate for women in science.

Factory Records released Unknown Pleasures, English band Joy Division’s debut album, on June 15, 1979. Following guitarist and lyricist Ian Cutis’s death just under a year later, keyboardist and guitarist Gillian Gilbert joined the remaining members and Joy Division became New Order. Both bands were nominated as one act for induction into the Rock and Roll Hall of Fame in 2023 and 2025 but failed to earn enough votes for admission.

I’m sure you’re asking yourself what this has to do with Jocelyn Bell Burnell or radio pulsars. Well …

In 1970, Harold Craft, a radio astronomer at the Arecibo Observatory in Puerto Rico, created a ridgeline plot of the radio emissions given out by a radio pulsar for his 1970 doctoral dissertation to visualize smaller pulses with larger ones. One of Joy Division’s members – either Stephen Morris or Bernard Sumner – saw Craft’s image and instructed Peter Saville, the designer of Unknown Pleasures’ artwork and packaging, to use it for the album’s cover.

Saville reversed the image from black-on-white to white-on-black, against the band’s stated preference for the original. “The group asked for it to be white on the outside and I just couldn’t see it … I was afraid it might look a little cheap. I was convinced that it was just sexier in black. This is radio energy from space. Space is black,” said Saville, according to Proximity.

Unknown Pleasure’s cover, seen here on the left, is considered one of the greatest album covers ever created. Susie Goldring, reviewing the album for BBC Online wrote, “The duochrome Peter Saville cover of this first Joy Division album speaks volumes. Its white-on-black lines reflect a pulse of power, a surge of bass, and raw angst. If the cover doesn't draw you in, the music will.”

So that explains the radio pulsar angle. How does Jocelyn Bell Burnell fit into this? Glad you asked …

The radio pulsar Craft repeated 80 times to create his ridgeline plot for his 1970 dissertation was originally named CP 1919 and was discovered on November 28, 1967, using the Interplanetary Scintillation Array of the Mullard Radio Astronomy Observatory in Cambridge, UK. The first discovered radio pulsar, CP 1919 is also known as PSR J1921+2153, is located in the constellation of Vulpecula, and was detected by individual observation of miles of graphical data traces.

And who was it that discovered the first radio pulsar that became part of a dissertation that included an image that was then used to create an album cover so iconic it was used by Disney for a Mickey Mouse t-shirt?

Jocelyn Bell Burnell.

Getting To Know Jocelyn Bell Burnell

Jocelyn Bell Burnell was born July 15, 1943, in Lurgan, County Armagh, Northern Ireland. Her father, G. Philip Bell, was an architect who helped design the Armagh Planetarium where she was often visited and was encouraged by staff to pursue a career in astronomy.

Bell Burnell grew up in Lurgan, attending the Preparatory Department of Lurgan College from 1948 to 1956. She was expected to follow the norms of the time and study cooking and cross-stitching but, after her parents and others challenged the school’s policies, was able to study science, according to Scientific Women.

“The real eureka moment for me was when I was reading a book by Fred Hoyle where he was talking about these big galaxies, you know, 100,000 million stars,” Bell Burnell told Short Wave. “Hoyle was talking about how these galaxies rotate, spin about their center. And we’re learning about this in school, and Hoyle’s talking about these galaxies with stars rotating. And what keeps them going around in a circle and not flying off into space? Wow, I like this physics. I could be an astronomer and do this for a job.”

She completed her secondary education in 1961, graduating from The Mount School, a Quaker girls’ boarding school in York, England. “She graduated from the University of Glasgow with a Bachelor of Science degree in Natural Philosophy (physics) in 1965,” writes Scientific Women, “and obtained her Ph.D. degree from New Hall (since renamed Murray Edwards College) of the University of Cambridge in 1969.”

According to Brittanica, Bell Burnell taught at the University of Southampton from 1970 to 1973 before joining University College London as a professor from 1974 to 1982. She also held a teaching position at the Open University from 1973 to 1987 and worked at the Royal Observatory in Edinburgh from 1982 to 1991.

She later became a professor of physics at the Open University from 1991 to 2001. Following this, she served as the dean of science at the University of Bath from 2001 to 2004 before taking on a role as a visiting professor at the University of Oxford.

Bell Burnell was appointed Commander of the Order of the British Empire (CBE) in 1999 and was later honored as a Dame (DBE) in 2007. She became a Fellow of the Royal Society in 2003 and served as president of the Royal Astronomical Society from 2002 to 2004. In 2008, she was elected president of the Institute of Physics for a two-year term. Her contributions to science were further recognized in 2021 when she was awarded the prestigious Copley Medal.

What Is A Radio Pulsar?

Bell Burnell was the subject of a recent Short Wave podcast on which she explained, “Bigger stars, at the end of their life, explode dramatically. They usually brighten up. They kick out a whole lot of gas and stuff into space, and the core gets kicked against, gets compressed, and gets shrunk right down.

“Massive stars, more than 20 times bigger than our sun, eventually collapse into black holes, infinitely small points of immense mass that we can't directly see. Then there are smaller stars, still bigger than our sun, that don't fully collapse into black holes.”

These types of stars are known as neutron stars because that’s what they’re composed of and those neutrons were “created when the pressure from the explosion compressed the protons and electrons so tightly together, they combined,” adds Short Wave host Regina Barber.

The core of the star becomes a ball that’s about 10 miles across, spinning very rapidly. A chunk of a neutron star the size of just a sugar cube would weigh about as much as a mountain on Earth – about a billion tons – and because of that compression, these stars have much stronger magnetic fields.

“The strong magnetic field keeps the charged particles constrained, and having lots of energetic, charged particles confined to a small volume and whizzing around like fury will likely give you radio waves,” Bell Burnell says. Since very few neutron stars shine light they can only be detected through the radio waves that they give out.

“These radio waves shoot out of the magnetic poles of some of these neutron stars as they spin,” Barber says. “And on Earth, you’ll only detect the radio waves if they happen to sweep across our planet like the beam of a lighthouse.”

Bell Barber adds, “It looks like a pulse. That’s why these particular stars are called Ps.”

Discovering “Little Green Men”

As a research assistant at Cambridge in 1967, Bell Burnell helped construct and operate a large radio telescope. “It looked like an agricultural frame, something you might grow peas up – a lot of wires and cables strung from posts over a space the size of 57 tennis courts,” she told the University of Cambridge. “It was built to study radio emission from quasars. I built the prototype and then six of us took two years to build the real thing. It was unglamorous but it functioned very nicely and switched on the first time I used it.”

Bell Burnell told Short Wave she was “the person operating this radio telescope, looking for radio waves from stars and galaxies, particularly quasars, out there in space. I can’t honestly remember what the definition was at the time I started, except that they were intriguing and mysterious.”

While reviewing the printouts of her experiments monitoring quasars, Bell Burnell discovered a series of extremely regular radio pulses. Puzzled, she consulted her adviser, astrophysicist Antony Hewish, and their team spent the ensuing months eliminating possible sources of the pulses, which they jokingly dubbed LGM (for Little Green Men) in reference to the remote possibility that they represented attempts at communication by extraterrestrial intelligence.

“Radio telescopes pick up human-generated interference: arc welders, sparking thermostats, badly suppressed cars,” Bell Burnell told the University of Cambridge. “I had to identify this interference and got quite used to recognizing features on the chart. Occasionally there would be something I didn’t recognize and I’d record it with a question mark or, as a joke, LGM for Little Green Men. It was easier than saying, ‘You know that funny pulsing source at right ascension 1919, declination plus 20.’ So, it became LGM.”

After monitoring the pulses using more sensitive equipment, the team discovered several more regular patterns of radio waves and determined that they were emanating from rapidly spinning neutron stars, which were later called pulsars by the press.

Before 1967 only about 20 quasars had been detected but Bell Burnell helped get that number 200. “We now know they’re galaxy-mass things (with) a huge black hole in their center which dominates their behavior in many, many ways,” said Bell Burnell. “And we probably know of thousands by now.”

Bell Burnell continues using radio wave detection to search for more quasars using the telescope’s antennae to detect and help focus the radio telescope on them. The receiver detects those signals and turns them into data points on a page that looks kind of like the marks on a polygraph.

“But in amongst all the data, there’s a little signal that doesn't make sense,” says Bell Burnell. “And the first couple of times I see it, I log it with a question mark and ‘doesn’t make sense – pass on.’ You know, there's real work to be done.”

As she continues collecting data, Bell Burnell sees the same signal several more times and realizes she now has multiple sightings, all from the same bit of sky, implying she has found something astronomical.

“You’re probably aware that the constellations you see in the night sky in summer are different from the constellations in winter,” explains Bell Burnell. “That’s because the stars go around in 23 hours, 56 minutes, not 24 hours. Well, this funny squiggle, whatever it was, kept to the 23-hour, 56-minute pattern. So it was keeping its place amongst the constellations, whatever it was.”

Bell Barber shared her plot of pulses with Hewish who said she needed to enlarge it. “The way you get an enlargement is to run the paper faster underneath the pen,” recalls Bell Burnell. “So, I had to go to the observatory at the time this thing was due to be observed and switch over to high-speed chart recordings.”

Eventually, she detected pulses again, this time in a string one-and-a-third seconds apart. The observation was repeated the next day, this time with Hewish in attendance, and it performed again. “We could see immediately it’s pulsing at the same rate as (the day before), Ball Barber said. “For something to keep pulsing steadily, it has to be big. But it also had quite sharp pulses, which meant it was small. So that was our conundrum, along with, what the heck could it be, and why is it going at this very fast rate of one-and-one-third seconds?

Hewish presented the data to an audience of scientists prompting them to look for more evidence of these pulsating radio waves. Soon, scientists concluded that the radio waves the telescope was picking up were from a neutron star’s pulse. And so, when spinning, they might sweep the radio waves across Earth.

And The Nobel Prize Goes To …

Not Jocelyn Bell Burnell, and her exclusion from the 1974 Nobel Prize in Physics remains one of the most well-known cases of scientific oversight. Despite her discovery of radio pulsars considered one of the most significant astronomical discoveries of the 20th century – revolutionizing our understanding of stellar evolution and compact objects – recognition went to Hewish and astronomer Martin Ryle.

Bell Burnell, despite her crucial role in detecting and analyzing the radio pulsars, was overlooked. At the time, it was common for Nobel Prizes to be awarded to senior scientists rather than students, but many have since argued that Bell Burnell’s contribution warranted inclusion.

Bell Burnell herself has remained gracious, acknowledging the Nobel system tends to recognize leaders of projects rather than individual contributors. She told the University of Cambridge, “My contemporaries were more upset about the Nobel than I was not to be recognized. One of them labeled it the ‘No-Bell’ prize! But it was fine by me. There’s no Nobel Prize in astronomy and I was proud that it was my stars that had convinced the prize committee that there was good physics in astrophysics.”

Nevertheless, her omission from the award has fueled ongoing discussions about gender bias in science. In later years, she received numerous prestigious accolades, including the Copley Medal and a $3 million Special Breakthrough Prize, which she donated to support underrepresented groups in physics.

When asked by the University of Cambridge about her discovery, Bell Burnell said, “The next generation of telescopes will see millions of events per night with computers that sift through huge amounts of data. If we had had access to a computer, we would never have programmed it to look for something so unexpected.

“How do you pick up the things you don’t know exist, the things you can’t tell it to look for? My project was to study quasars, and then we accidentally stumbled over these things called pulsars. They were totally unexpected, totally unknown – and it’s been huge fun.”