To any fan of the band Joy Division, the data visualization of a pulsar embroidered on their 1979 debut studio album "Unknown Pleasures" is an iconic piece of post-punk history. But the history behind the data visualization is complex and eluded Scientific American's Jen Christiansen for months before he encountered Cornell graduate Harold D. Craft, Jr.’s PhD thesis, “Radio Observations of the Pulse Profiles and Dispersion Measures of Twelve Pulsars” (1970). 

Craft explained the process of his pulsar visualization to Christiansen:  

“[When] pulsars were discovered [and the radio telescope] Arecibo, it turned out, was the perfect instrument to measure these things, because it had enormous sensitivity – easily the most sensitive instrument in the world at that time. It also had the rudiments of digital technology there, because it was a radar observatory, and the radar folks were using digital technology. Radio astronomy folks, including myself at the time, were primarily using – would you believe it – chart recorders, or very slow analogue to digital converters….We were young graduate students, we didn’t know squat. But, here’s something new in astronomy that hadn’t been seen before, and we were at the best instrument in the world to look at them, and what better opportunity was there than that? So we just hopped on it.

This plotting of sequences started just a little bit earlier when we were looking at potentially drifting sub-pulses within the major pulse itself….I … wrote a [computer] program that, instead of having these lined up vertically… tilted them off at a slight angle like that so that it would look like you were looking up a hillside – which was aesthetically interesting and pleasing, but on the other hand, it just confused the whole issue.

I would give [these images] to a woman draftsperson in the space sciences building at Cornell, and she would then trace this stuff with india ink, and make a much darker image of it, so that it could be printed basically.

A colleague in the space sciences department, who is now a professor of astronomy at Cornell, Jim Cordes, saw me on the street…and he said, “Oh, by the way, did you know that your image is on the cover of Joy Division?” And, I said no, I had no clue. So I went to the record store and, son of a gun, there it was.”