The mysterious cover of Joy Division's 1979 debut Unknown Pleasures – a black-and-white visualization of pulsar data that looked like digital mountain peaks – is the subject of a new, in-depth Scientific American article. The magazine traced the origins of the "computer-generated illustration" to its first publication around 1970.
A few years ago, the cover was the subject of a four-minute documentary, Data Visualization Reinterpreted: The Story of Joy Division's "Unknown Pleasures" Album Design, in which graphic designer Peter Saville ruminated on the cover and pulsars (a star that emits repeating series of radio waves similar to a lighthouse beam). He explained that the band had given him a page from the Cambridge Encyclopaedia of Astronomy (1977 edition, Scientific American notes) and "very astutely spotted this image as potentially a wonderfully enigmatic symbol for a record cover."
Saville explained that the image was the first time the frequency of a pulsar signal was demonstrated, beginning with a research group at Cambridge. "The diagram itself is a cutting of the continuous read out and then a stacking," he said. "So what you're seeing is this comparative chart of the frequency and the accuracy of the signal." He went on to discuss how fascinated he was with fans adopting the diagram on apparel and tattoos for their own interpretation.
Scientific American reported that the image on the cover of Unknown Pleasures was not the first time a pulsar had been graphed. That took place in 1967 in Cambridge, England. The magazine traced Joy Division's particular image to one created by the Arecibo Radio Observatory and published in 1970 by Dr. Harold D. Craft, Jr. in his PhD thesis titled, "Radio Observations of the Pulse Profiles and Dispersion Measures of Twelve Pulsars."
In a new interview with Scientific American, he explained that he and a group of classmates worked together at Arecibo. He also recalled developing the program that graphed the illustration. The images the computer made were then traced with India ink to stand out more.
Regarding Joy Division's use of the image, Craft said it was a total surprise. A Cornell astronomy professor he was friends with was the first to bring the album to his attention. "I went to the record store and, son of a gun, there it was," Craft said. "So I bought an album, and then there was a poster that I had of it, so I bought one of those, too, just for no particular reason, except that it's my image, and I ought to have a copy of it."
For further reading, Scientific American delves deep into the science of pulsars and the means by which the image was made.