Jacqueline Hochheiser, Corporate Communications

Summary:

  • Jocelyn Bell Burnell discovered the first pulsar as a PhD student at Cambridge University with her radio astronomy professor, Tony Hewish.
  • Burnell, Hewish and three university volunteers made the discover with a radio telescope they built themselves.
  • Burnell found a pulsing signal of radiation she called “scruff,” which pulsed at regular, extremely fast intervals all over the sky.
  • Burnell and Hewish, with input from other highly regarded astronomers, determined that the “scruff” was the result of a unique type of neutron star they named a pulsar.

Today, Mini-Circuits celebrates Ada Lovelace’s birthday. If you don’t know her name, Ada Lovelace was an English mathematician from the early 19th century who rose to prominence when she published the first algorithm intended for use on a revolutionary computer prototype called the “Analytical Machine” that she theorized could one day perform any number of complex tasks. She even wrote a primitive programming language that would allow the machine to generate Bernoulli numbers. She published the revolutionary paper in relative anonymity under the cryptic nom-de-plume “A.A.L.” It wasn’t revealed until 20 years after her death that A.A.L. was, in fact a woman named Augusta Ada Lovelace.

Today, Lovelace’s legacy is held up as an example to girls and women pursuing studies and careers in STEM fields. In the spirit of Lovelace’s memory, we’re kicking off a new series on great women in the RF/microwave engineering with a look at Jocelyn Bell Burnell, an astrophysicist from Northern Ireland responsible for the discovery of the first pulsar in 1967, which revolutionized radio astronomy and had a far reaching influence on our understanding of the universe.

Bell Burnell was born July 15, 1943 in Lurgan, Northern Ireland. Her father was an architect and contributed to the design of the Armagh Planetarium, which still operates today. She grew up visiting the planetarium and reading her father’s astronomy books, which instilled a love for exploring concepts that extended beyond Earth at an early age. Her parents were supportive of her interests from the get go, but when she started to attend preparatory school at Lurgan College, the family was disappointed to find out that girls were not encouraged to study science. Instead, their curriculum included such topics as cooking and cross-stitching.

“My parents hit the roof,” Bell Burnell recalls. “Along with the support of the other parents they demanded a curriculum change.”

Her parents later moved her to a girls’ Quaker boarding school, where she was allowed to indulge in science classes at which she quickly excelled. Bell Burnell continued to follow her passion through university, earning her Bachelor’s degree in physics from the University of Glasgow in 1965.

She continued her studies at the University of Cambridge where she studied astrophysics in pursuit of her PhD. It was here, under the supervision of her radio astronomy professor, Tony Hewish, that Bell Burnell would break ground on her monumental discovery of pulsars.

Jocelyn Bell Burnell

The journey began when Hewish decided to build a radio telescope in the hopes of finding quasars, super-massive black holes surrounded by a gaseous cloud, for research. Burnell and Hewish would use the telescope to detect interplanetary scintillation (IPS) to help them locate the quasars. IPS refers to the random fluctuations in the intensity of radio waves given off by celestial objects.

The telescope took two year to build between Burnell, Hewish, and three student volunteers. It covered an area of around four and a half acres, about 57 tennis courts worth of space, and operated with four receiver beams. Burnell had sole responsibility of operating the telescope and analyzing its data by hand instead of using a computer. Hewish believed that analysis by the human eye was better suited to recognizing changes in signal pattern. Going through the telescope data by hand would also be a useful tool to train Burnell in recognizing signal patterns and familiarize her with operating a radio telescope.

After eight weeks of tracking the telescope’s readings, Burnell started to observe a pulsing signal of radiation that she referred to as “scruff.” The pulse occurred in the same position of the sky each night at such regular intervals Burnell and Hewish originally believed it was artificial and coming from extraterrestrials on a distant planet.

As a result, the signal was dubbed “little green men,” but the theory was soon debunked after further scrutiny. In order for the radiation to transmit from a planet, the signal would display doppler shifts as the planet revolved around its sun. A doppler shift refers to the change in wave frequencies during the motion between a wave source and its observer. However, there were no doppler shifts present in Burnell’s mysterious “scruff.”

As research continued, similar “scruff” began to appear speckled over the sky all appearing at precise, regular intervals. It was determined that the signals were emanating from unique masses of matter that were given the name “pulsars” due to their pulsing nature. After a star dies, its matter condenses into a small core under extreme pressure to create a pulsar, which then spins at a rapid rate to produce intermittent beams of light.

Chart showing Burnell’s first evidence of a pulsar.

Because of their unique pulsing characteristics, pulsars have become a popular focus of study. The specific behavior of pulsars also helped scientists study and understand other cosmic happenings such as measuring cosmic time and distance, as well as studying matter under extreme conditions.

Antony Hewish, Photo Courtesy of NobelPrize.org

Hewish would later be awarded a Nobel Prize in physics for the discovery, although Burnell would not. At the time of the discovery, Burnell was still a student and not technically a professional. “I believe it would demean Nobel Prizes if they were awarded to research students,” she admitted in an interview. This was also during a time when female scientists were few and far between in a male dominated profession.

Although technical and scientific fields are still widely male-dominated, Mini-Circuits is a proud supporter of the women in our engineering work force. With the help of our partnership with the Society of Women Engineers (SWE), we have created an inclusive and innovative culture within our company. SWE is an organization acts as a mentorship and career guidance program to help women in male dominated professions.

Despite not sharing in the glory of a Nobel Prize, Burnell is widely recognized by the astronomy community for her role in the discovery of pulsars. She has continued to bring innovative ideas to the scientific community as a professor of gamma ray astrology at the University of Southampton and as the president of the Royal Astronomical Society from 2002 to 2004.

In 2018, Bell Burnell received the Special Breakthrough Prize in Fundamental Physics for her pulsar discovery. She then donated the entire £2.3 million prize money to help female, minority and refugee students seeking to become physics researchers. This act became known as the Bell Burnell Graduate Scholarship Fund.