Bell Burnell and the Little Green Men

Jocelyn Bell and the LGM-1

This year, I plan to grow my collection of portraits of women in STEM. I thought I'd get an early start on this project, with my first portrait of a scientist who is still working.

This is a linocut portrait of Jocelyn Bell (now Bell Burnell) and the incredible radioastronomy dataset she gathered when only a graduate student in 1967, working with Anthony Hewlish. The block is inked "à la poupeé" in dark blue grey and green on Japanese kozo paper. The first edition is a variable run of 10 prints, each 10" by 12.5" (25.4 cm by 31.8 cm).

In November, 1967, Jocelyn Bell (Burnell) was just a graduate student when she discovered the first radio pulsar (or pulsating star), a highly magnetized, rotating neutron star that emits a beam of electromagnetic radiation. This radiation (light in the radio frequency band) can only be observed when the star is pointed towards us; so, like the light from a distant lighthouse, it appears to pulse at a precise frequency. Jocelyn Bell had been working with her supervisor Antony Hewish and others to construct a radio telescope to study quasars (quasi-stellar objects which emit radio waves). She noted some "scruff" on her chart-recorder, and then that the pulses were incredibly regular, occurring every 1.337 seconds. Hewish was initially scornful and insisted the regular pulses must be noise from a human made source. He first dubbed this object, emitting with such regularity 'LGM 1' for "Little Green Men 1", a playful joke about their uncertainty about what could emit radiation so regularly - obviously it could only be a communication from extraterrestrials hahaha! After she found other such sources, in different places with different frequencies, her colleagues became convinced. These discoveries lead to the development of the pulsar model. LGM-1 is now known PSR B1919+21.

The 1968 paper announcing this discovery in Nature has five authors, lead by Hewish, followed by Jocelyn Bell. In 1974, Hewish won the Nobel Prize for this discovery, (along with fellow radioastronomer Marlin Ryle). Jocelyn Bell was not included as it was assumed that the "senior man" was responsible for the work. This was controversial and has been condemned by many leading astronomers like Fred Hoyle (who with Thomas Gold was first able to explain the signals as due to a rapidly rotating neutron star). Jocelyn Bell Burnell herself has stated she was not upset. Bell Burnell has a great career and won many honours after her impressive start, but her exclusion from the Nobel win, based on her own research strikes me and many others as one of the more blatant and egregious examples of gender bias in the selection of Nobel prize recipients.

Cover of Joy Division's 1979 album 'Unknown Pleasures'
designed by Peter Saville, using the pulsar data
from the Cambridge Encyclopaedia of Astronomy

Not only the discovery, but the presentation of the data is impressive and elegant. The famous diagram (I've included behind her, and shown above) shows superimposed images of successive pulses. Stripped down to their essential information like sparklines (chart lines without annotation or axes, but drawn of course to a common scale) so their regularity really stands out, and they can be easily compared and contrasted. If you are used to looking at time series, you'll know that since they can be easily superimposed and the pulses line up, that the frequency is quite regular. The diagram is downright eloquent, and visually appealing, so it has been included in books on data visualization and was used in the iconic design of Joy Division's 'Unknown Pleasures' album. From there the diagram itself has become a sort of visual meme and can be found in all sorts of different media and reinterpreted in everything from tattoos to fashion. (You can read my take on this meme itself here: Astrophysical Meme: Jocelyn Bell Burnell's Pulsar, Little Green Me, Joy Division and Beautiful Data ).