Burning bright

Fifty-five years ago, Jocelyn Bell Burnell discovered “pulsars”. Her supervisor won the 1974 Nobel prize in physics and there have now been three Nobels for work on these super-dense stars, none of which has gone to her. But Bell Burnell is sanguine. “Not getting the Nobel has been good for me because I’ve been given pretty much every other prize!” she tells me.

Bell Burnell’s discovery has spawned a vast field. Most famously, Einstein’s theory of gravity was confirmed by the spiralling together of two pulsars in a “binary pulsar,” earning Russell Hulse and Joseph Taylor the 1993 Nobel. This year, there have even been hints of a hidden population of pulsars that until now have been too faint and obscure for us to spot.

In 2018, Bell Burnell was awarded the £2.3m Special Breakthrough prize, the world’s largest award for science. She spent the money on helping disadvantaged groups—women, ethnic minorities and refugees—do research in physics. Bell Burnell’s experience shows how important this is.

At her school in Lurgan, Northern Ireland, her parents had to fight for her to study science rather than cooking and sewing. The sole woman doing physics at the University of Glasgow, she was jeered at by male students, who banged desks whenever she entered a lecture theatre. “I learnt not to show weakness, not to show it was affecting me,” she says.

A summer job at Jodrell Bank radio observatory near Manchester did not lead anywhere: Bell Burnell was told that the director, Bernard Lovell, did not favour female students. Instead she did graduate study at Cambridge in 1965, building a strange radio

telescope—the brainchild of her PhD supervisor, Anthony Hewish, who died last year. Covering four acres, it consisted of a grid of 4,096 vertical wooden poles, or “dipole antennas”, strung together by a cat’s cradle of wires. Its output was recorded by a line traced out by a pen on a cylindrical roll of paper. “There were about 100 feet to scrutinise every day,” says Bell Burnell.

On the chart, on 28th November 1967, she noticed a bit of “scruff”: a radio burst repeating every 1.3 seconds. It was initially pooh-poohed by Hewish, certain it was manmade radio interference.

Bell Burnell thought there had been a mistake admitting her—a woman from Northern Ireland—to Cambridge, and so worked extra hard to postpone the day when, inevitably, she would be found out. It paid off. She found three more pulsing radio sources, or pulsars.

Cambridge astrophysicist Fred Hoyle guessed correctly that a pulsar is a “neutron star”, a relic of a supernova explosion that packs the mass of the sun into the volume of Mount Everest. This should be too small to be seen, but some neutron stars sweep a lighthouse beam of radio waves across the sky as they spin, appearing as pulsars.

The media, however, focused on Bell Burnell being a woman. “I was asked how many boyfriends I had had, what were my vital statistics and whether, for photos, I could undo a button or two on my blouse,” she says.

Over the past half a century, Bell Burnell has worked in many fields of astronomy. The pen-recorder trace of her first pulsar appears on Ulster Bank’s £50 note. Most astronomers think she was unfairly overlooked for the Nobel. Hoyle believed he himself was snubbed for the prize for criticising the Nobel committee for not having given one to Bell Burnell. He once told me: “I was miserable for three days. Then it struck me the history books will credit me and that is all that matters.” The history books have most certainly credited Jocelyn Bell Burnell.