When contacted, dozens of SAGE veterans who worked in the program between 1958 and 1983 (the approximate lifetime of SAGE) recalled witnessing this pin-up program firsthand. Not surprisingly, the pin-up's role changed over the decades as the technological culture shifted around it. While Tipton insists the pin-up had a diagnostic purpose, SAGE operators in later decades remember it as a lighthearted way to pass the dull hours of the late shift when traffic was slow or the standby machine was not in service ("At no time was the primary mission of air defense compromised to my knowledge," wrote one veteran in an email to the author.)

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Viewing this ancient digital artwork today, one naturally wonders who created it. "I remember at the time that everybody knew it was done by an IBM programmer," recalls Tipton. Robert Martina, a veteran of early SAGE installations in the 1950s, agrees with Tipton. "IBM guys were supposed to be so straight. They weren't," he adds with a laugh. But no one seems to recall who exactly at IBM created it.

Going by accounts from Tipton and others, the pin-up program likely dates from 1956 to 1958. The upper end of the year range, 1958, can easily be established because multiple eyewitnesses claim that the diagnostic was present when the first non-test SAGE site went live in New Jersey in early 1958. The lower end of the range, 1956, comes from a compelling piece of cultural evidence.

In 1955, famed pin-up artist George Petty resumed a relationship with Esquire magazine just before his retirement. He illustrated two calendars for the publication, one for 1955 and one for 1956. Each month's page came accompanied by a lushly illustrated and extremely scantily clad Petty pin-up.

Petty had a way of painting a woman by which she almost appeared nude if not for a sheer, skin-hugging fabric that obscured almost nothing. Such is the case in the December 1956 calendar pin-up, which leaves little besides the woman's mysteriously absent nipples to the imagination.

As it turns out, this illustration matches the SAGE pin-up almost exactly (as you can see in the comparison below), as if someone directly traced her outline and translated it into vector coordinates. It's likely that whoever created the pin-up image used a technique similar to those used to encode maps and coastlines into vector segments for display on the system.

Since the Esquire 1956 Girl Calendar was likely printed in mid-late 1955 to prepare for the coming year, and that painting was created specifically for the calendar, the pin-up could not have originated from before that time. It may have even been created when the December 1956 image was hanging on the wall nearby.

As it happens, in 1955, IBM began educating specially selected Air Force personnel as part of the first SAGE training program at its facilities in Kingston, New York. It's possible that IBM instructors at Kingston devised the pin-up diagnostic an amusing way to immediately engage a group of all-male, usually 18-24 year old computer novices. But until more information surfaces -- or someone comes forward to claim credit -- the author shall remain unknown.